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i Evaluating the Sustainability Credentials of the Passivhaus Standard in Comparison to Traditional Construction Techniques David Michael Baines Submitted as Part Requirement for the B.A (Hons) degree in Civil Engineering at Newcastle University May 2012
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Page 1: Passivhaus Dissertation

i

Evaluating the Sustainability Credentials of the Passivhaus Standard

in Comparison to Traditional Construction Techniques

David Michael Baines

Submitted as Part Requirement for the

B.A (Hons) degree in Civil Engineering

at Newcastle University

May 2012

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Executive Summary

This report considers the requirement for sustainable homes and determines that fossil fuel depletion,

levels of carbon dioxide emissions and the increasing costs of energy are key issues. The UK is now a

net energy importer and the UK government is imposing increasingly stringent regulation on carbon

emissions and therefore ‘low energy’ housing is of increasing importance.

Studies show that newly constructed dwellings are under achieving in terms of thermal performance.

The causes of this under-performance are addressed in the Passivhaus standard.

Passivhaus is an energy standard that uses basic principles, such as air tightness, super insulation and

the removal of thermal bridges to vastly reduce a buildings energy demand. The construction

techniques used in Passivhaus show similarities to conventional construction methods, but with much

more stringent quality control measures and attention to detail. Through the use of the Passivhaus

Planning Package, it is claimed that specific heating demand can be reduced by up to 90%.

Through site visits and meetings with professionals involved with Passivhaus design, the UK’s first

carbon neutral office and a £8.7 million Passivhaus primary school have been used as case studies to

assess their sustainability credentials.

The relationship between Passivhaus and other environmental assessment methods, such as BREEAM

and the Code for Sustainable Homes has been assessed. The report concludes that Passivhaus is

narrow in its focus as it considers only energy efficiency in its approach to sustainability. However, this

does not restrict the implementation of other methods of improving sustainability, such as photo-

voltaic panels and wind turbines as well as other forms of renewable technologies.

Code for Sustainable Homes level 3 is current standard building practice in the UK. A cost comparison

has been carried out to compare the differences between this standard and Passivhaus. At present,

there is a Passivhaus cost uplift of around 15%, however, this cost difference could be decreased as

wide-spread adoption of Passivhaus takes place and the UK workforce becomes more familiar with its

design. A separate comparison of heat demand has been conducted and concluded that a Passivhaus

primary school can have a reduced heating demand of over 90% in comparison to other existing

schools.

The report also considers the disadvantages of the standard which include the cost uplift, the higher

levels of site supervision and quality control required, as well as the unavailability of certain

components in the UK marketplace.

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The report concludes that Passivhaus is a more sustainable solution compared to conventional

building. Although it focuses on energy saving only, this does not preclude it from other forms of

sustainable development. Passivhaus could be an important tool in the Government’s CO2 reduction

targets for 2050.

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Table of Contents

Executive Summary............................................................................................................................... ii

List of Tables and Figures ...................................................................................................................... v

Acknowledgements ............................................................................................................................. vi

Abbreviations ...................................................................................................................................... vi

1. Introduction ................................................................................................................................. 1

2. The Requirement for More Sustainable Homes ............................................................................ 2

2.1 Lessons from Stamford Brook ............................................................................................... 2

3. Passivhaus: An Introduction ......................................................................................................... 4

4. Passivhaus: Basic Principles .......................................................................................................... 5

4.1 Defining the Standard ................................................................................................................ 7

4.2 Construction Techniques ............................................................................................................ 8

4.2.1 Foundations ........................................................................................................................ 9

4.2.2 Window / wall interface .....................................................................................................10

4.2.3 Roof ...................................................................................................................................11

5. Case Study: Interserve Construction Ltd, Leicester Office ............................................................12

6. Case Study: Richmond Hill Primary School, Leeds ........................................................................13

7. Passivhaus, BREEAM and Code for Sustainable Homes ................................................................14

7.1 Bolt-on renewable technologies ..........................................................................................16

7.1.1 Case study: Barley Mow Primary School .............................................................................17

8. Alternative Methods ...................................................................................................................18

9. Sustainability Issues ....................................................................................................................20

9.1 Economic Effect of Passivhaus ...................................................................................................20

9.1.1 Cost Comparison ................................................................................................................21

9.2 Comparison of Specific Heating Demand ...................................................................................22

9.2.1 Richmond Hill Primary School .............................................................................................22

9.2.1 Montgomery Primary School ..............................................................................................23

10. Disadvantages: ........................................................................................................................24

11. Discussion ...............................................................................................................................26

12. Conclusions and Recommendations ........................................................................................28

References ..........................................................................................................................................30

Appendices..............................................................................................................................................33

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List of Tables and Figures

Figure 1: Basic Principles of Passivhaus

Figure 2: Typical Passivhaus foundation and floor slab construction

Figure 3: Typical Passivhaus Window detail

Figure 4: Typical Passivhaus Roof Detail

Figure 5: Interserve Leicester Office

Figure 6: Office MVHR System

Figure 7: Foundation Insulation Instalment

Figure 8: Denby Dale Passivhaus

Figure 9: Barley Mow Wind Turbines

Figure 10: Passivhaus / CSH 3 Cost Comparison

Figure 11: Cost comparison of Passivhaus and Code Level 3

Figure 12: Specific Heating Demand – Richmond Hill

Figure 13: Specific Heating Demand – Montgomery Primary

Table 1: Energy Performance Targets and Design Component Values

Table 2: Passivhaus / CSH Comparison

Table 3: Alternative Architecture for Sustainability

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Acknowledgements

I have received a wealth of information from various professionals within the construction industry.

I would like to thank Interserve Construction Ltd, Space Group Architects and Billinghurst George and

Partners for their cooperation.

The information they were able to provide on the building industry and the Passivhaus standard has

proved to be an invaluable resource throughout this project.

Abbreviations

CO2 – Carbon Dioxide

MVHR – Mechanical Ventilation Heat Recovery

PHPP – Passivhaus Planning Package

OSB – Oriented Strand Boards

SIP’s – Structural Insulated Panels

BSF – Building Schools for the Future

GIA – Gross Internal Area

DFEE - Dwellings Fabric Efficiency Target

BREEAM – Building Research Establishment Environmental Assessment Method

CSH – Code for Sustainable Homes

IAQ – Indoor Air Quality

SAP – Standard Assessment Procedure

BedZED – Beddington Zero Energy Development

DEC – Display Energy Certificates

PV – Photo – Voltaic

NHBC – National House Building Council

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1. Introduction

This report aims to introduce the Passivhaus standard and provide an understanding of the key

principles involved in its implementation. Information will be gathered from published resources, site

investigations and meetings with professionals in the industry to be able to evaluate the sustainability

credentials of Passivhaus.

This report aims to compare the sustainability performance of Passivhaus with the current standard

building practice in the UK, as well as finding comparisons in other alternatives for sustainable

development. The construction techniques will be discussed and the key differences between

Passivhaus and standard building practice will be highlighted to show the reasons for any difference in

sustainability performance.

The three pillars of sustainability; economic, social and environmental will be considered throughout

the report to assess what impact the adoption of Passivhaus could have on the UK.

This report also aims to evaluate the relationship between Passivhaus and other sustainability

performance standards, such as ‘BREEAM’ ratings and the ‘Code for Sustainable Homes’.

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2. The Requirement for More Sustainable Homes

The adoption of more sustainable housing is of increasing importance due to three main factors: 1)

fossil fuel depletion, 2) climate change due to Carbon Dioxide (CO2) emissions, 3) the increasing cost

of energy.1

In 2004, the UK made the transition from Net Energy Exporter to Net Energy Importer and the level of

energy importation is expected to rise. Fuel prices are increasing, concerns have been raised over the

security of energy supplies and there have been shortages of gas imports in recent winters. 2

Global levels of CO2 are a growing concern and efforts are being made to reduce CO2 emissions in

order to reduce its impact on climate change. In 2006, it was stated that the UK’s 21 million homes

were responsible for 27% of the carbon dioxide (CO2) emissions.3 The UK Government produced an

ambitious plan for all new homes to be zero carbon from 2016, although the budget reform in 2011

relaxed the initial criteria by excluding cooking and electrical appliances.4 The aim of this legislation

was to reduce CO2 emissions by 80% on 1990 levels by 2050.5

It is not possible to sustain the current upward trend in levels of energy use in buildings. Even if the

climate change argument were to be disregarded, issues involving the consistently increasing energy

costs and increasing risks of fuel poverty cannot be ignored and make a powerful argument toward

the need for low energy housing.

2.1 Lessons from Stamford Brook

There are many building standards currently in place that aim to reduce the environmental impact of

housing, many of which are evaluated in this report. A study conducted at Leeds Metropolitan

University, entitled “Lessons from Stamford Brook”6 monitored the energy performance of over 700

dwellings. The study focused upon the energy and carbon performance of the dwellings, which were

constructed to an enhanced energy performance standard, EPS08, exceeding the building regulations

at the time (construction began in 2004, EPS08 is around 15% in advance of the 2006 Building

Regulations in England and Wales in terms of energy performance). This study has particular relevance

in this report as it reveals how this low energy housing performed and provides recommendations on

how the performance could be improved.

The report concluded that there can be significant discrepancies between the performance of a

dwelling as designed and that realised. Many new homes are not meeting their carbon emissions

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reduction targets with an average performance gap of around 60% between their designed heat loss

standards and those realised after construction. Tests found that the dwellings fell short of the design

expectations and performance targets for the following reasons;

- Thermal performance was found to be compromised mainly due to thermal bridging and

unnecessary air leakage.

- Traditional construction methods do not lend themselves to efficient thermal performance.

- Thermal under performance was due to the need for revised theoretical modelling tools and

models.

- Low level understanding of thermal design

- Very little thermal performance measurement and under developed processes and change

control systems

- Lack of continuity of insulation and air barrier

“The recent dramatic shift in the UK government’s regulatory targets, designed to achieve zero carbon

new homes within 10 years, has made it even more important that the lessons from the project are

absorbed and acted upon by the government, the industry, its supply chain, educators and others who

are part of the industry’s supporting infrastructure.”7 Lessons from Stamford Brook, 2007

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3. Passivhaus: An Introduction

Passivhaus is the fastest growing energy standard in the world, with around 30,000 certified structures

to date. Devised in Germany in the early 1990’s by Professors Wolfgang Feist and Bo Adamson8, the

standard is a simple approach to more sustainable building where excellent thermal performance and

very high levels of air tightness are achieved.

Capable of being applied in any climate, meticulous attention to detail is required in design and

construction, alongside impeccable quality assurance procedures, to provide a high level of occupant

comfort and vastly reduced heating demand compared to a conventionally built structure.

Passivhaus does not require the use of central heating system. Heat demand can be satisfied through

a small heater that is integrated into the Mechanical Ventilation Heat Recovery (MVHR) system. The

MVHR system is utilised to provide excellent air quality and highly efficient heat recovery.

In essence, a Passivhaus is “a building in which a comfortable interior climate can be maintained

without active heating and cooling systems ”9 Wolfgang Fiest, 1988

To achieve an official Passivhaus certification, the dwelling must undergo an independent quality

control process. The process is undertaken by an external, Passivhaus Institute accredited certifier.

Achieving the Passivhaus certification ensures the building is performing to the Passivhaus standard

and has the potential to add value to the property in the future.10

The Passivhaus Institute claim that energy savings of up to 90% compared to typical existing buildings

and over 75% compared to average new builds are achievable.

Figure 1: Basic Principle of Passivhaus Source: www.greenhammer.com/passive_house

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4. Passivhaus: Basic Principles

A Passivhaus is based on some fundamental design principles which aim to lower the heating

requirement and therefore lower energy consumption;

- Super Insulation:

A Passivhaus building requires excellent thermal insulation providing a barrier between the

internal and outdoor climates.

- Good indoor air quality:

Increased health and comfort provided by a Mechanical Ventilation Heat Recovery (MVHR)

system with highly efficient heat recovery.

- Triple glazed windows:

Internal heat to be contained within the building, whilst optimising heat gain from the sun.

Windows on south elevation are larger than those on the north. The traditional, non-

passivhaus approach is to place radiators below windows to increase the air temperature and

improve comfort levels. This is avoided in the Passivhaus standard, high specification triple

glazed windows are used with frames embedded into wall insulation.

- Air tightness:

Air leakage is a major cause of energy loss. Older houses tend to be more airtight than modern

housing, due to less precise modern workmanship and materials assembly.11 Passivhaus

implements a “continuous uninterrupted airtight building envelope”.12

- Minimal thermal bridging:

Thermal bridges are localised areas of the building envelope where heat flow is increased.

Thermal bridges result in heat loss and result in lower internal surface temperatures and

condensation.13

- High Volume to external surface ratio

- Optimisation of passive solar gains:

Appropriate positioning and orientation of building to maximise solar effects.

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Passivhaus Planning Package (PHPP):

The PHPP is a spreadsheet based design tool used to check that a building is going to be compliant

with the design standard. The first Passivhaus building was constructed in Germany in 1992. Energy

data has been collected over subsequent years and the buildings have consistently met the PHPP

predictions.

The Passivhaus standard does not impose stringent requirements regarding domestic hot water,

lighting or appliance consumption. Instead, the standard imposes an overall limit on the primary

energy demand to promote energy efficiency throughout the dwelling.

The basic principles detailed above show many similarities to the recommended areas of

improvement highlighted in the “Lessons from Stamford Brook” report. This suggests that Passivhaus

principles may go some way in improving the performance of these energy efficient building systems.

The remainder of this report aims to evaluate if this is the case.

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Table 1: Energy Performance Targets and Design Component Values Source: Passivhaus Institute, Approved Document L1A – Building

Regulations 2010

4.1 Defining the Standard The following table shows the criteria that must be met for a dwelling to be classified as a Passivhaus.

Where appropriate, typical values from standard building practice meeting the current requirements

of the building regulations have been provided as a comparison.

The figures in Table 1 demonstrate that the Passivhaus standard imposes much more stringent

restrictions on thermal performance than the current UK building regulation requirements.

Passivhaus

UK Building

Regulation / Standard

Practice

Energy Performance Target Limiting Value Typical Value

Specific Heating Demand ≤ 15 kWh/m2/ yr 79 kWh/m²/yr

Specific Heating Load ≤ 10 W/m2 50 W/m²

Specific Primary Energy Demand ≤ 120 kWh/m2/yr 290 kWh/m2/yr

Design Component

Walls (U value) ≤0.15 (W/m2K) 0.30 (W/m

2K)

Roof (U value) ≤0.15 (W/m2K) 0.20 (W/m2K)

Floor (U value) ≤0.15 (W/m2K) 0.25 (W/m2K)

Windows (U value) ≤0.8 (W/m2K) 2.0 (W/m2K)

Doors (U value) ≤0.8 (W/m2K) 2.0 (W/m2K)

Air tightness (m3/(h.m²) @50pa)

Note: Passivhaus requirement is 0.6 air changes per hour ≈ 0.65(m

3/(h.m²)

@50pa)

0.65 10 (m3/(h.m²) @50pa)

Thermal bridging (linear ψ value) ≤0.01 (W/m²K) ≤0.15 (W/m²K)

MVHR coefficient (η HR) ≥0.75 --

Ventilation electric limit 0.45 Wh/m3 --

Appliances High efficiency

recommended --

Lighting High efficiency

recommended --

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The specific heating demand and specific heating load have to be reduced by a factor of five, while

specific primary energy demand is cut by a factor of three.

A ‘U’ value can be defined as “...a measure of heat loss in a building element such as a wall, floor or

roof. It can also be referred to as an ‘overall heat transfer co-efficient’ and measures how well parts of

a building transfer heat. This means that the higher the ‘U’ value, the worse the thermal performance

of the building envelope.”14 Table 1 show that the ‘U’ values need to be reduced for all areas of the

building envelope.

Air tightness and elimination of thermal bridges are key aspects of the Passivhaus concept and are

reduced by a factor of 15. The construction methods used to achieve this increased performance are

explained in ‘Construction Techniques’.

4.2 Construction Techniques

This section discusses some of the construction techniques that have been used to achieve the

Passivhaus standards and compares them with more traditional building techniques. Information

delivered in this section of the report has been obtained through discussions with structural designers

that have experience with Passivhaus design.15

It is important to note that Passivhaus design can encompass a wide range of building techniques and

materials, for example the walls can be cavity masonry walls or structural timber framed. The focus is

on very high levels of insulation and air tightness and reduction of thermal bridges.

The same end results can be achieved even though different materials and building techniques are

used. In Passivhaus design a great deal of attention to detail is implemented and all junctions are

carefully detailed to minimise thermal bridging and achieve high air tightness levels.

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Figure 2: Typical Passivhaus foundation and floor slab construction Source: Passivhaus Diaries, Bill Butcher

4.2.1 Foundations

A conventional house built to current standard practice would have a 600mm wide concrete strip

foundation with a cavity masonry wall built from the foundation. The cavity wall would typically be

100mm dense concrete block inner leaf with 100mm cavity (filled with concrete below ground level)

and 100mm dense concrete block outer leaf. The floor slab would be 100mm of concrete laid on

50mm of insulation board. The floor slab would be poured up against the perimeter wall.

This can be compared with a typical Passivhaus design using similar techniques of cavity masonry

walling. The concrete strip foundations would be similar but wider than above to accommodate a

much wider cavity. The cavity would be 300mm wide to accommodate insulation which would be

taken down to the strip footing to reduce thermal bridging. To further reduce thermal bridging the

inner leaf of masonry would utilise aerated concrete blockwork in lieu of dense concrete blockwork as

this is much more thermally efficient.

Some designs also incorporate foam glass blocks into the inner leaf below ground level which also

significantly reduces thermal bridging effects. The floor slab will be laid on 225mm of polyfoam

insulation and the slab will be laid on top of the inner leaf at the wall/floor junction so that the edge of

the slab will be effectively built into the inner leaf. This helps to avoid air leakage which would

inevitably result from the conventional construction described above when the concrete slab shrinks

and a gap opens up around the perimeter against the wall.

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Figure 3: Typical Passivhaus Window detail. Source: Passivhaus Diaries, Bill Butcher

4.2.2 Window / wall interface

A conventional house would typically use double glazed windows with outward opening sashes and

aluminium spacer bars between the glass. The window would only nominally overlap with the

insulation in the cavity (although it is becoming standard practice now to include thermally insulated

cavity closers).

This can be compared to a typical Passivhaus design, where the windows have very low ‘U’ values and

are triple glazed with 20mm cavities and low emissivity coatings which are designed to reflect heat

back into the building. The spacer bars are made from low thermal transmittance materials.

The opening sashes are inward opening which allows the larger frame section to be on the outside to

enable the use of more insulation around the frame. The insulated window frame fully overlaps with

the wall cavity insulation. The frame is fitted into a prepared opening formed by a plywood lining built

into the masonry which is completely sealed against the masonry using special tapes and seals. The

outside jambs, head and sill of the window incorporate preformed closure pieces that are sealed to

the window and brickwork.

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Figure 4: Typical Passivhaus Roof detail Source: Passivhaus Diaries, Bill Butcher

4.2.3 Roof

A conventional house would use typical trussed rafters at 600mm centres with a small eaves overhang

and an eaves detail where the ceiling tie intersects the sloping rafter member at the wall plate

junction. This detail leaves very little scope to make the cavity wall insulation continuous with the roof

insulation due to the restricted space available. Typical roof insulation would be 300mm thick and a

plasterboard ceiling would be fixed directly to the underside of the ceiling tie.

This can be compared to a typical Passivhaus design where the roof insulation would be a minimum of

500mm thick. The trussed rafters would incorporate a special ‘bobtail’ feature where the end of the

trussed rafters at wall plate position have a 500mm high timber section which allows the insulation to

fully overlap with the wall insulation, thus reducing thermal bridges.

The ends of the rafters will often over-sail the eaves to provide solar shading for the summer months.

The underside of the ceiling ties will have 18mm OSB (orientated strand board) fixed to the underside

and then battens and a plasterboard ceiling. This allows the air tightness to be achieved and avoids

puncturing the air seal line as service cables can be accommodated in the void created by the battens

between the OSB and the plasterboard ceiling.

This information summarises the fundamental differences in the construction techniques of the

Passivhaus standard. For further information on construction methods and detailed drawings supplied

by the architect, refer to appendices item 1.

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Figure 5: Interserve Leicester Office Source: Taken on-site

Figure 6: Office MVHR System Source: Taken on-site

5. Case Study: Interserve Construction Ltd, Leicester Office

Interserve is one of the world’s foremost support services and construction companies. They claim to

– “have been championing sustainability for over 10 years and have in place strong leadership and

robust management to keep at the forefront of industry best practice”

Interserve Construction Ltd required a new office

facility as their current offices, built in the 1940’s,

were very expensive to run. The decision was made

to produce a Passivhaus office, the first carbon

neutral commercial office in the UK. “Running at a

mere 10% of the energy usage of such a building

constructed conventionally”.16 Interserve, 2012

Interserve has provided their energy bill figures to aid

this report. The energy costs in the old office were £23,336 per annum in 2010. The predicted annual

energy costs in the new office, based upon the figures calculated by mechanical and electrical

designers were around £3,000 per annum. This equates to an annual

cost saving of around £20,000.

The new office project cost around £1.5 million. There is a projected

10 year accumulated saving of £319,000 (assuming 10% annual fuel

increase). There is also an estimated extra-over Passivhaus

construction cost of £180,000, which represents a 5 year pay back.

The average weekly energy bill was around £400 in the old office

building whereas a weekly bill in March this year totalled £11.30

(although it should be considered that 2012 has seen an unusually

warm March and the new office has also implemented photovoltaic

panels and an earth tube ventilation system which reduce energy demand).

In the first week of December and once again in the first week of April the office building was

generating more energy than was being consumed. Energy Performance Certificates can be seen in

apprendice Item 2.

Estimates suggest that Passivhaus should reduce cost of energy by 90% compared to an office built to

current building regulations; however the current measured performance exceeds this. These figures

suggest that Interserve is very positive about their decision to utilise the Passivhaus standard and are

experiencing good financial reward as a result.17

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Figure 7: Foundation Insulation Instalment Source: Taken on-site

6. Case Study: Richmond Hill Primary School, Leeds

Interserve Construction Ltd also made the decision to tender for a £8.7 million primary school in Leeds

using a Passivhaus design, as requested by the client. They won the tender and construction is

currently underway (April 2012). It is hoped that the school will use 80% less energy than a

conventionally built school as well as reducing carbon emissions by 60%.18

Structural Insulated Panels (SIP’s) were attached to the steel frame of the structure. Air tightness has

been the biggest challenge faced on site, these panels provide a air tight barrier and possess excellent

thermal properties. A steel frame was used with the SIP’s panels fixed to the outside. The specific heat

demand of the school is now 14.8kWh/m²/annum, which is a slight improvement on the

15kWh/m²/annum requirement.

Thermal modelling using the PHPP, the total heat loss due to thermal bridging is expected to be

around 5%, as compared to around 20% on a traditional build.19

One of the differences between Richmond

Hill and non-Passivhaus schools is the

attention paid to the reduction of thermal

bridging at foundation level. As can be seen

in Figure 7 - foam glass blocks were

introduced between the pile caps and steel

column foundation. Refer to Appendice Item

3 for further details on this design detail.

Whilst visting the site, it was obvious that rigourous quality control meaures were in place and the site

management team needed to be heavily involved in ensuring the tradesmen could adapt to the

unfamiliar construction techniques.

To provide a comparison of construction costs, Richmond Hill can be compared to other non-

Passivhaus schools. The Building Schools for the Future (BSF) scheme, which aims to rebuild every

secondary school in England, has been in operation since 2005. The BSF average construction cost is

£1850 per m².20 Richmond Hill has a Gross Internal Area (GIA) of 4010m² and the school cost around

£8.7 million in total. This equates to £2170 per m².

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Figure 8: Denby Dale Passivhaus Source: selfbuild-central.co.uk

7. Passivhaus, BREEAM and Code for Sustainable Homes

The Building Research Establishment Environment Assessment Method (BREEAM) is a method used to

rate buildings on environmental performance. BREEAM claim to “...set the standard for best practice

in sustainable building design ... one of the most comprehensive and widely recognised measures of a

building’s environmental performance”.21

The Code for Sustainable Homes (CSH) is an environmental assessment method for rating and

certifying the performance of new homes based on BRE Global's EcoHomes scheme.22The code aims

to reduce carbon emissions and create homes that are more sustainable. The code covers

“energy/CO2, water, materials, surface water runoff (flooding and flood prevention), waste, pollution,

health and well-being, management and ecology.”23A rating is given from 1 to 6, where level 6 is the

most sustainable. Since 2010, CSH level 3 has been building standard for UK homes.

The case study of Denby Dale house, West Yorkshire, can be used to provide a performance

comparison between a Passivhaus certified dwelling and other buildings;

- Denby Dale was developed to be a low cost

and easily replicable example of Passivhaus,

aimed at providing a solution to the

requirement for reducing CO² emissions in

UK housing. Denby Dale was not put under

CSH testing, however, using current Standard

Assessment Procedures (SAP) it is clear that

the project would not have received a CSH

rating of more than 3.

- ‘Kingspan Lighthouse’ is a Net Zero carbon dwelling developed at BRE’s innovation park. It has

estimated fuel bills of £30 per annum and achieves CSH level 6.24

- ‘Old Apple Store’ was built to provide a value sustainable development using low impact

construction materials. This building achieves a CSH level 5. 25

- ‘Norbury Court’ is a development consisting of nine bungalows constructed in 2007. It was the

first social use building in Staffordshire. It achieved a CSH level 3. 26

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Table 2: Passivhaus / CSH Comparison Adapted from table by Green Building Store

Source: greenbuildingstore.co.uk/page--passivhaus-and-csh

‘U’ values and air tightness are good indicators of the thermal performance of a structure. In table 2,

Denby Dale Passivhaus have been compared to other ‘low energy’ buildings;

Table 2 shows that the CSH rating is not proportionate with the actual energy loss performance of the

structures and suggests that the method of categorizing structures on their energy performance needs

to be revised. Research published by Jim Parker, CSH assessor, concluded that a “Passivhaus dwelling’s

energy savings are not realistically represented by its CSH rating. Many buildings receiving higher CSH

ratings actually perform worse but gain points in other areas, sometimes through the use of ineffective

and expensive bolt-on renewable technologies.”27Jim Parker, 2009

The accurate modelling of thermal bridging is critical to predicting the heat loss of a building. The

current UK method for achieving this, using SAP, uses a rudimentary and generalised assessment of

thermal bridging, ultimately resulting in an underestimate of the heating requirement.28 The PHPP

requires much more detail for each junction in the building design. Although this approach is more

laborious it achieves a far more accurate calculation of thermal performance to be expected.

“We would like CSH to get rid of SAP and incorporate the much more accurate Passivhaus Planning

Package (PHPP) as its energy calculation methodology"29. Bill Butcher, Construction manager at Denby

Dale, 2009

U values [W/m²K]

Project CSH Floor Walls Windows Roof Air tightness

(m3/h@50pa)

Denby Dale

(Passivhaus) 3 0.104 0.113 0.8 0.096 0.6

Kingspan

Lighthouse 6 0.11 0.11 0.7 0.11 1

Old Apple

Store 5 0.15 0.14 1.2 0.12 2.17

Norbury

Court 3 0.21 0.29 1.2 0.2 5.63

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The BREEAM rating of a building could come under criticism. BREEAM and CSH appear not to focus

sufficient attention on the main aspects that affect a buildings energy performance. Described by

some in the industry as a ‘tick box’ exercise, BREEAM and CSH can actually offer incentives that result

in designs that can be damaging to a project’s sustainability credentials. Examples of this can be found

at Beddington Zero Energy Development (BedZED) and the Nottingham University eco-homes. In both

instances, biomass boilers were installed in order to meet the CO2 requirements, however bio-mass

was abandoned or never used due to the increased maintenance required and so traditional gas

boilers are in operation instead. 30

Passivhaus has little or no connection with BREEAM or Code for Sustainable Homes and one does not

necessarily infer that it will automatically be reflected in the rating of another. Evidence of this can be

provided in the Display Energy Certificate (DEC) database. DEC’s provide information about the energy

usage of a building where a rating of ‘A’ to ‘G’ is awarded, ‘A’ being the most energy efficient. The

Devonshire Building, Newcastle University provides a good example of BREEAM ratings and energy

efficiency levels not matching. The building achieved a BREEAM Excellent rating, however, it is ‘G’

rated with a thermal energy consumption of 292kWh/m²/annum – almost 20 times that of a

Passivhaus.

7.1 Bolt-on renewable technologies

Renewable technologies used for electricity generation are not part of the Passivhaus standard, but

could be used to assist with further efforts to construct more sustainable buildings.

Installation of an electricity generating technology from a renewable or low carbon source, such as

solar Photo-Voltaic (PV) panels or wind turbines could generate income from the governments feed-in

tariff scheme. Initially, estimates of a £12,500 typical installation cost and £25,000 pay back over a 25

year period were published31. However, tariffs are set to decrease as UK Government plans changes in

the tariff rate in late 2012.

Feed in tariffs are available for;

- Photo-Voltaic panels - Wind turbines - Hydroelectricity - Anaerobic Digestion - Micro Combined heat and power.

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Figure 9: Barley Mow Wind Turbines Source: barleymowprimary.org

7.1.1 Case study: Barley Mow Primary School

Barley Mow Primary School, Chester le Street, was constructed in 2010. South Tyneside and

Gateshead planning permission dictated that on-site generation of renewable energy would be

required , with a target of 10% of the total energy requirements.32 For this reason, ‘bolt-on’ renewable

technologies, in this case wind turbines, were installed. Passivhaus principles alone would not meet

such planning requirements and a Passivhaus scheme would therefore also need renewable energy

technology in place. However, it should be noted that the energy use would be drastically lowered if

Passivhaus were to be used and therefore the 10% energy demand from renewable resources could

be met through fairly small scale renewable implementation.

In this particular case study, social problems were encountered when it was found that the turbines

generated noise in operation, causing disruption to the assembly hall below. The turbines are

therefore only used at night.33

The Passivhaus approach reduces carbon emissions without the need for renewable technologies,

which run the risk of break down or failure. It appears that renewable technologies attempt to solve a

problem that the Passivhaus standard aims to avoid. Passivhaus is a much different approach to the

government’s strategy of offsetting carbon rich energy through implementing expensive bolt-on

renewable technologies.

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Table 3: Alternative architecture for sustainable building Adapted from table produced by Hanne Tine Ring Hansen, 2009

Source: blog.buildingseurope.eu/2009/01/30/is-a-passive-house-a-sustainable-building

8. Alternative Methods

Passivhaus is arguably more sustainable than dwellings constructed to standard building regulations.

However, it is important to note that Passivhaus does not represent a holistic approach to achieving

sustainability. Energy consumption is the focus of the Passivhaus standard, however, it is just one of

many factors that affect a dwellings sustainability credentials. Table 3 below shows various areas that

are considered when assessing the sustainability of a building and compares Passivhaus to other forms

of sustainable architecture.

Fin

anci

al

C

on

sid

erat

ion

s

Tran

spo

rt

Po

lluti

on

Was

te

Hea

lth

& W

ell

Bei

ng

Ener

gy C

on

sum

pti

on

Mat

eria

ls

Wat

er

Soci

al &

Cu

ltu

ral V

alu

e

Lan

d u

se a

nd

Eco

logy

Self-sufficient architecture

Ecological architecture

Bio-climatic

Green architecture

Solar architecture

Low-energy architecture

Environmental

Passivhaus

The more areas of sustainability that are considered in the design, the more comprehensive and

holistic the method. From table 3 it is clear that Passivhaus is focused upon reducing energy demand

and does not consider the other areas of sustainability.

“The fact that the Passive House standard does not consider whether the house is located in an area

with Combined Heat and Power (CHP) with a low carbon emission footprint is a major weakness …”

Hanne Tine Ring Hansen, 2009

Varies from project to project

Common for all projects

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It is important to note that energy efficiency is only a small part of achieving sustainability. However, it

can be argued that energy is the most important factor to consider when attempting to improve the

sustainability credentials of a building and should therefore be the main area of focus.

As previously stated, the future security of the UK’s energy supply is questionable and the constant

increase in energy prices has a large social impact on consumers. Government targets to reduce CO2

emissions are being enforced more stringently with each edition of building regulation.

These findings suggest that Passivhaus can be used in part of a well balanced sustainable

development, but to optimise performance other factors should be comprehensively considered.

The statement below is a quote from the Client’s of Denby Dale Passivhaus, and shows the viewpoint

of the type of people that would adopt a more sustainable lifestyle and embrace the Passivhaus

standard.

“…We should be looking for ways to support sustainable energy, not by building more nuclear power

stations, but by saving energy. The British government should be responding more actively to

encourage energy saving buildings. We hope that our house will show that it is viable for any builder to

construct a modest Passivhaus at a modest price that will result in significant savings on world

resources” Clients of Denby Dale, Geoff and Kate Tunstall, August 2009.

If this statement is reflective of the general public’s opinion then this shows strong support towards a

reduction in domestic energy consumption and the promotion of the Passivhaus standard.

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9. Sustainability Issues

Passivhaus aims to promote sustainable development. Sustainable development can be defined as –

“Development that meets the needs of the present without compromising the ability of future

generations to meet their own needs”.34

Sustainability originally referred only to ‘environmental sustainability’ or ‘ecological sustainability’,

however, the areas of ‘social’ and ‘economic’ sustainability are now realised to be of high importance.

Together, these three key areas make up the ‘three pillars of sustainability’.

9.1 Economic Effect of Passivhaus If Passivhaus becomes more widespread throughout the UK, it would encourage a reduction in

household fuel consumption. This would reduce the country’s dependency on fossil fuels and reduce

the number of residents living in ‘fuel poverty’.

“A household living in a 70m² Passivhaus with gas heating could spend as little as £25 on space heating

per year.” 35 CEADA, 2012

In current economic times it is important to reduce CO2 emissions in the most cost effective ways

possible. Passivhaus uses an approach that aims to increase energy efficiency from first principles,

which is a more effective method than the use of mountable renewable technologies on a less

efficient building.

The construction of Passivhaus will affect the local economy. Currently, some high quality components

used in the construction are generally imported into the country from the continent. As Passivhaus

increases in popularity and the UK is able to adapt to the increased energy performance standards,

more opportunity will develop for UK manufacturers and suppliers to profit. The project manager at

Richmond Hill Primary School, Leeds, noted that there are limitations to certain components due to

the strict accreditation process required to meet Passivhaus standard. The air handling system, used

as part of the MVHR system, needed to be imported from Sweden. However, the windows, SIP’s

panels and insulation were supplied from Chesterfield, Manchester and Leeds respectively, therefore

helping to support manufacturers and suppliers in surrounding areas.36

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Figure 10: Passivhaus / CSH 3 Cost Comparison Source: Bere:Architects

Figure 11: Cost Comparison of Passivhaus and Code Level 3 Source: Bere:Architects

9.1.1 Cost Comparison

In assessing the sustainability of the Passivhaus standard it is important to consider the financial

aspects of the design. An experiment has

been carried out to compare the

construction costs of a code level 3

house, (which is equal to current

building regulation).and a Passivhaus.

The experiment was carried out by

Bere:Architects in Ebbw Vale, Wales.

Two houses of equal internal volume

were constructed to enable the

difference in construction costs to be

compared.

The study found that the total cost of Passivhaus construction was £96,677, taking 68 days to

complete. The total cost of the Code Level 3 house was £83,651, taking 70 days to complete. This

equates to an increased cost of around 15%. For the raw data used to form Figure 11 and refer to

Appendices Item 4.

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

Co

st (G

BP

)

Cost Comparison of Passivhaus and Code Level 3

Passivhaus

Code Level 3

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Chantry Middle School

Amble County Middle School

Horton Grange First School

Seaton Hirst C of E Middle School

Bellingham Community Middle School

Blyth Tynedale County Middle School

Bothal Middle School

Diamond Hall Junior School

Farringdon Primary School

Chilton Primary School

Langley Park Primary School

Richmond Hill Primary Passivhaus

Figure 11: Specific Heating Demand – Richmond Hill Primary School

9.2 Comparison of Specific Heating Demand 9.2.1 Richmond Hill Primary School

Data has been obtained from Display Energy Certificates to provide a comparison of Richmond Hill

Primary School to other schools of a similar size. Primary Schools in the North of England with a Gross

Internal Area (GIA) the same as Richmond Hill (+ / - 10%) have been selected as a comparison.

Figure 11 displays the results of this comparison;

It has been calculated using PHPP that Richmond Hill will have a heat demand of 13 kWh/m²/annum.37

The mean heat demand of the other primary schools is 184 kWh/m²/annum.

Refer to Appendices Item 5 for the raw data used to create this chart.

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Essendine Primary School

Purley Oaks Primary School

Benthal Primary School

Burnt Ash Primary School

Commonswood Jmi School

Betty Layward Primary School

Caldecote Primary School

Montgomery Passivhaus

Figure 13: Specific Heating Demand – Montgomery Primary

9.2.1 Montgomery Primary School

Located in Exeter, Montgomery Primary School has a capacity of 450 students and achieved

Passivhaus accreditation in February 2012.

Figure 13 shows a comparison between Montgomery School and other schools across the UK with the

same number of students.

It has been calculated using the PHPP that Montgomery Primary will have a heat demand of 15

kWh/m²/annum. The mean heat demand of the other primary schools is 152 kWh/m²/annum.

In conclusion, the mean energy demand of the two Passivhaus School’s is 14 KWh/m²/annum.

The mean energy demand of all of the non-Passivhaus school’s is 172 KWh/m²/annum..

This shows a difference in energy demand of almost 92%.

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10.Disadvantages:

One of the most obvious disadvantages of adopting the Passivhaus standard is the cost uplift. The

Passivhaus Institute state the cost uplift is around 7%, however, results analysed during this report

have concluded costs could be increased by as much as 15%. However, the large savings in energy

costs mean that the payback period is relatively short.

After meeting with the project manager during the construction of Richmond Hill Primary School,

there were several draw backs that he encountered;

- More site management is required with greater levels of supervision and guidance. Quality

control is of upmost importance and a large amount of photographic evidence was required to

provide proof of correct procedures. Inspections carried out on a regular basis.

- Increased complexity of design details required a full time, site based design manager, adding

to staffing costs.

- Mistakes made during construction are difficult to rectify without first considering how any

changes could affect the stringent air tightness standards.

- Passivhaus construction generally requires more time than traditional methods. Construction

programme estimated to be around 6 weeks longer (adding around 10% onto total

construction time) compared to traditional construction methods.

The Architect involved on Richmond Hill Primary School commented;

- There is a lack of knowledge of the Passivhaus standard, particularly with the fitting of services

as this is the area that most differs from conventional construction.

- Larger requirement for a fully collaborative team and communication.

- UK manufacturers are slow to adapt to what is required in terms of verification of

performance, which is much more stringent for Passivhaus. The availability of suppliers is

limited and as such could lead to less competitive tendering. “This is fundamental for wide

adoption of Passivhaus, Austria for example, have government funded accreditation for their

‘home grown’ suppliers and manufacturers and as such can now build to Passivhaus standard

at no extra cost” Space Architects, 2012

There is a danger of the term “Passivhaus” being used to describe dwellings that have been designed

to be more energy efficient and indeed include some of the Passivhaus principles, however, have not

achieved official Passivhaus accreditation.

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A study published by the University of Dublin, “Defining Zero Energy Buildings – A Life Cycle

Perspective”, determined that in order to achieve the last unit of KWh/m² reduction required to meet

the Passivhaus standard the embodied energy of the building was increased and the reduction in

energy consumption achieved was counter-balanced. This suggests that the 15KWh/m² requirement

could be too stringent and that better overall results could be achieved with a slightly less stringent

requirement.

Passivhaus is dependent upon mechanical ventilation. Business development manager at Interserve’s

Leicester office suggested that some members of the public feel that the air tightness and reliance on

MVHR systems can make them feel uncomfortable and / or claustrophobic and may believe that it

could have negative side effects on health.

Research conducted by the National House Building Council (NHBC) in 2009 identified a range of

studies from the UK and other countries which point to a link between Indoor Air Quality (IAQ) and

health of occupants. “Evidence from a few studies points to the fact that, working correctly, MVHR is

able to have a positive effect on IAQ and health, but clearly this can only be expected to be realised in

practice if the system is functioning correctly.”38

On the whole, very few criticisms of the Passivhaus standard have been found. Although Passivhaus is

increasing in popularity; relatively little has been published on the subject. While conducting research

for this report, an effort has been made to obtain information that is unbiased and represents an

honest depiction of the Passivhaus standard. However, it is important to note that some of the

professionals questioned throughout the formation of this report are actively involved in the

promotion of Passivhaus and may have financial incentives for Passivhaus to increase in popularity.

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11.Discussion

From the data analysed in the formation of this report, it appears that Passivhaus offers a much more

sustainable solution to building than the current building regulations and it can be expected to

increase in popularity in the foreseeable future.

The experiences of construction manager, Bill Butcher, responsible for the construction of Denby Dale

Passivhaus, West Yorkshire, have led him to believe that “Passivhaus is the way forward for the UK. It

can help create quality, comfortable buildings while also achieving 90% cuts in occupants’ fuel bills. It

offers the UK an easy win solution towards the massive cuts in CO2 emissions we need to make -

urgently.”39

Currently, Passivhaus is more expensive to construct than traditional / main stream techniques.

However, the UK is currently experiencing a ‘Passivhaus learning curve’ where many difficulties

currently experienced can be rectified through gaining familiarity with the Passivhaus standard which

will increase the efficiency of construction while decreasing the time and costs.

There are many alternatives to the Passivhaus standard. So-called ‘green buildings’ have energy

usages that are largely unknown. Their performances are not often measured and often poorly

modeled using Standard Assessment Procedures (SAP), therefore ‘zero carbon’ and ‘low energy’

buildings are being built with no official certification. The PHPP offers an absolute measure and

provides the users with clear results. It is capable of determining what effect particular changes will

have on the end result. Other sustainability standards, for example, the Code for Sustainable Homes is

not so clear in its operation. A large amount of variation is allowed whereas the Passivhaus limitation

of 15 kWh/m²/annum is clear and final.

It is not possible to state which method of eco-friendly building is superior. Different methods have

their merits and criticisms and the most sustainable solution could be a combination of different

methods, depending on the individual circumstance of the build.

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Within the Approved Document L 2013, a proposal has been made to set a dwellings fabric efficiency

target (DFEE). The DFEE is expressed as kWh/m²/annum which correlates directly with the unit

measurement used for Passivhaus projects. The figures proposed for 2016 (taken from the zero

carbon hub) are 39kWh/m²/annum for apartments and mid-terraced houses and 46kWh/m²/annum

for end terrace, semi detached and detached properties. The Passivhaus’s requirement is

15kWh/m²/annum and will therefore result in much greater energy savings.

Location is an important factor in the performance of a Passivhaus. A study by the ‘Promotion of

European Passive Houses’ entitled ‘Energy Saving Potential’ highlighted that the figures related to the

Passivhaus’ ability to reduce energy consumption must be considered specific to each country.

In the UK, “the total primary energy use of a Passive House is 32% of that of an existing dwelling.

Compared to a typical new dwelling, a Passive House in the UK shows a total primary energy use of

41% and an energy use for space heating of 23%. In both cases a reduction of energy use for domestic

hot water of 50% is expected”40 Promotion of European Passive Houses, 2006

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12.Conclusions and Recommendations

Although sustainability is comprised of many areas, energy demand is arguably the most important

and pressing issue that needs acting upon. It is not possible to sustain the current upward trend in

levels of energy use in buildings and modern buildings are not meeting their stated energy

performance targets.

There are many key areas that are considered when assessing the sustainability of a building, including

energy / CO2, water, materials, waste, pollution, health and well-being, management and ecology.

Although Passivhaus focuses upon maximising energy efficiency and could not be considered a holistic

approach, it does not detract from any of these other key areas. It provides an excellent base from

which other sustainability driven technologies can be applied.

Construction of a Passivhaus requires meticulous attention to detail where great importance is placed

upon insulation, air tightness and thermal bridging. The case studies in this report suggest that the UK

workforce is capable of adapting to the differences in design and the increased quality control

procedures.

The Passivhaus institute claim that “Passive Houses allows for energy savings of up to 90% compared

with typical Central European buildings stock and over 75% compared to average new

builds”41Passivhaus Institute, 2012.

Analysing the results of the display energy certificates for schools and comparing them to Richmond

Hill and Montgomery Primary Schools, energy demand has been reduced by approximately 92%. This

suggests that there is truth behind the Passivhaus Institute’s claims of achieving 90% energy

reductions on existing buildings.

BRE acknowledge that the carbon emissions target of 2050 is not achievable as things stand.

Suggestions have been made of implementing code for sustainable homes level 6 immediately in

order to improve the carbon emissions performance. However, Passivhaus has demonstrated that it

could have major part to play and potentially be a better alternative in reducing CO2 emissions.

Many people will be unclear on what an ‘eco-home’ consists of as other sustainability standards are

not easily defined and are not easily modelled. Through the use of the PHPP, consumers can be clear

on what design parameters they are trying to achieve as Passivhaus is focused with set aims. It is not

prescriptive in how the targets are met and leaves the methods of achieving the targets to personal

preference, dependant on the individual case. For this reason it is easily defined and understandable.

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This study has shown that Passivhaus is much more sustainable than current building standards

construction and could be considered to have an important part to play in the government’s target to

reduce CO2 emissions.

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References 1 Why Sustainability is Important. Sustainable Housing Foundation. [Online] [Cited 3rd March 2012] http://www.sustainablehousingfoundation.com/about-shf/why-is-sustainability-important/ 2 Energy Imports and Exports. Paul Bolton. [Online] [Cited 20th April 2012] http://www.parliament.uk/briefing-papers/SN04046.pdf 3 Carbon Zero Homes Plan Unveiled. BBC News. [Online] [Cited 20

th April 2012]

http://news.bbc.co.uk/1/hi/sci/tech/6176229.stm 4 Budget 2011: Zero-carbon homes plan 'watered down. The Guardian. [Online] [Cited 20th April 2012] 'http://www.guardian.co.uk/uk/2011/mar/23/budget-2011-zero-carbon-homes 5 Energy Efficiency in New and Existing Buildings. BRE Trust.2010. [Cited 2nd May 2012] 6 Evaluating the Impact of an Enhanced Energy Performance Standard on Load – Bearing Masonry Domestic Construction. Leeds Metropolitan University. [Online] [Cite 26

th March 2012]

http://www.leedsmet.ac.uk/as/cebe/projects/stamford/pdfs/del8execsum.pdf 7 Evaluating the Impact of an Enhanced Energy Performance Standard on Load – Bearing Masonry Domestic Construction. Leeds Metropolitan University. [Online] [Cite 26

th March 2012]

http://www.leedsmet.ac.uk/as/cebe/projects/stamford/pdfs/del8execsum.pdf 8 The Passivhaus Standard. BRE. [Online] [Cited 3rd March 2012] http://www.passivhaus.org.uk/standard.jsp?id=37 9 Passive Solar House Design. Adamson 1987 and Fiest 1988. [Online] [Cited 2nd April 2012] http://www.creategreenhome.com/Passive_Solar.htm 10 Why Passivhaus Certification. Passivhaus Homes. [Online] [Cited 2nd April 2012] http://www.passivhaushomes.co.uk/whycertify.html

11 Refurbishment / retrofit: Airtightness. Greenspec. [Online] [Cited 2nd April 2012]

http://www.greenspec.co.uk/refurb-airtightness.php 12

General Principles for Improving Airtightness. Passipedia. [Online] [Cited 2nd

April 2012] http://passipedia.passiv.de/passipedia_en/planning/airtight_construction/general_principles/principles_for_improving_airtightness 13

Thermal Bridges. Passipedia. [Online] [Cited 2nd

April 2012] http://passipedia.passiv.de/passipedia_en/basics/building_physics_-_basics/heat_transfer/thermal_bridges 14 U values. John Brenan. [Online] [Cited 2

nd April 2012]

www.architecture.com/SustainabilityHub/Designstrategies/Earth/1-1-1-10-Uvalues(INCOMPLETE).aspx 15

Information gathered from Billinghurst George and Partners, Meeting held 2nd

May 16 Interserve. UK Construction Magazine. [Online] [Cited 2nd May 2012] http://www.ukconstructionmagazine.co.uk/online/uk_construction/uk_features/april2012/interserve.html 17 Information obtained via email from Business Development Manager, John Walkerdine, Interserve Construction Ltd, March 2012

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18 Interserve to Deliver Passivhaus Certified Leeds School. Interserve Plc. [Online] [Cited 2nd May 2012] www.interserve.com/news-media/press-releases-and-news/2011/10/25/1657/interserve-to-deliver-passivhaus-certified-leeds-school 19 Anecdotal, PM Richmond Hill, Jim Shaw, Interserve Construction Ltd, February 2012 20

The Building Schools for the Future Programme: Renewing the Secondary School Estate. National Audit Office. [Online] [Cited 20

th April 2012]

http://www.nao.org.uk/publications/0809/schools_for_the_future.aspx 21 What is BREEAM? BREEAM. [Online] [Cited 20th April 2012] http://www.breeam.org/page.jsp?id=66 22 Code for Sustainable Homes. BREEAM. [Online] [Cited 20th April 2012] http://www.breeam.org/page.jsp?id=86 23

Code for Sustainable Homes. Communities and Local Government. [Online] [Cited 21st

April 2012] http://www.communities.gov.uk/planningandbuilding/sustainability/codesustainablehomes/ 24

Lighthouse – Home Page. Kingspan. [Online] [Cited 21st

April 2012] www.kingspanlighthouse.com 25 Code for Sustainable Homes: Case Studies. Communities and Local Government. [Online] [Cited 21st April 2012] http://www.communities.gov.uk/publications/planningandbuilding/codecasestudies 26 Code for Sustainable Homes: Case Studies. Communities and Local Government. [Online] [Cited 21st April 2012] http://www.communities.gov.uk/publications/planningandbuilding/codecasestudies 27 Passivhaus Project Reveals Flaws in Code. Green Building Store. [Online] [Cited 21st April 2012] http://www.greenbuildingstore.co.uk/news--passivhaus-code-for-sustainable-homes.html 28 Passivhaus Project Reveals Flaws in Code. Green Building Store. [Online] [Cited 21st April 2012] http://www.greenbuildingstore.co.uk/news--passivhaus-code-for-sustainable-homes.html 29

Passivhaus Project Reveals Flaws in Code. Green Building Store. [Online] [Cited 21st

April 2012] http://www.greenbuildingstore.co.uk/news--passivhaus-code-for-sustainable-homes.html 30

Tarmac House. The University of Nottingham. [Online] [Cited 26th

April 2012] www.nottingham.ac.uk/~lazwww/creative_energy_homes/tarmac/index.html 31

Is Solar Power a Bright Investment? The Guardian. [Online] [Cited 26th

April] http://www.guardian.co.uk/money/2010/feb/06/solar-power-bright-investment 32 South Tyneside Local Development Framework. South Tyneside Council. [Online] [Cited 26th April 2012] http://www.southtyneside.info/CHttpHandler.ashx?id=3172&p=0 33 Anecdotal, information gathered from structural designer, Billinghurst George and Partners, March 2012 34 World Commissions on Environment and Development (1987:23). 35 What is Passivhaus? CEADA. [Online] [Cited 15th April 2012] http://www.ceada.co.uk/our-service/passivhaus/ 36 Anecdotal – Project Manager at Richmond Hill, Jim Shaw, Interserve Construction Ltd, March 2012. 37

Quote from Architect. David Savage, Space Architects, March 2nd

2012-05-08

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38 Mechanical Ventilation with Heat Recovery in New Homes. Zero carbon Hub. [Online] [Cited 3

rd May 2012] ,

January 2012 http://www.zerocarbonhub.org/resourcefiles/ViaqReport_web.pdf 39

Passivhaus Diaries, Part 20: Coming to an End. Bill Butcher. [Online] [Cited 3rd

may 2012] http://www.building.co.uk/passivhaus-diaries-part-20-coming-to-an-end/3159554.article 40 Energy Saving Potential. Promotion of European Passive Houses. [Online] [Cited 3rd May 2012] http://www.rockwool.com/files/rockwool.com/Energy%20Efficiency/Library/EnergySavingPotential.pdf 41

What is a Passivhaus? Passivhaus Institute. [Online] [Cited 4th

May 2012] http://www.passiv.de/en/02_informations/01_whatisapassivehouse/01_whatisapassivehouse.htm

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Appendices

Item 1.1 : Architects details of construction methods

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Item 1.2

Item 1.3

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Item 1.4:

Item 1.5 :

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Item 2.1: Energy Performance Certificates for Interserve Old Leicester Office.

This building achieved a G rating, meaning that it the building’s thermal performance was very poor

and the heat demand, especially during winter, would have been very high.

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Item 2.2: Energy Performance Certificate for Interserve New Leicester Office

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Item 3:

An example of one the differences between Richmond Hill and non-Passivhaus schools is the attention

paid to the reduction of thermal bridging at foundation level where at Richmond Hill foam glass bloack

where introduced between the pile caps and steel column foundation.

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Item 4.1: Raw Data for Ebbw, Wales Passivhaus Cost Comparison

Passivhaus Cost (£)

Code Level 3 Cost (£)

Foundations 1160 3501

Ground Floor 6233 3209

Frame 14604 13864

Roof 5212 4424

External Walls 11336 7785

Space Heating 16451 11241

Ventilation 6397 1082

Item 4.2: CSH 3 vs Passivhaus

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Item 5.1: Richmond Hill heat demand Comparison

School Energy Rating

GIA (m²)

Specific Heat Demand (kWh/m²/annum)

Chantry Middle School C 3,959 130

Amble County Middle School D 3,968 184

Horton Grange First School D 4,093 167

Seaton Hirst C of E Middle School D 4,124 146

Bellingham Community Middle School F 4,173 197

Blyth Tynedale County Middle School G 3,758 406

Bothal Middle School G 4,039 323

Diamond Hall Junior School C 3,935 109

Farringdon Primary School C 3,886 53

Chilton Primary School D 3,758 185

Langley Park Primary School C 3,947 128

Richmond Hill Primary Passivhaus A 4,010 13

Item 5.2: Montgomery Heat Demand Comparison

School Energy Rating

No. of pupils

Specific Heat Demand

(kWh/m²/annum)

Essendine Primary School E 450 146

Purley Oaks Primary School D 450 146

Benthal Primary School F 450 143

Burnt Ash Primary School E 450 150

Commonswood Jmi School E 450 145

Betty Layward Primary School E 450 144

Caldecote Primary School G 450 191

Montgomery Passivhaus A 450 15