BCS Preservation Brochure

Preservation Ltd

Preserving the Past, Protecting your Future

About Us

BCS Preservation is a Darlington-based contractor

specialising in property preservation and environmental

services. With over 45 years of experience in the

industry between the senior surveyors, we have a wealth

of knowledge in a wide variety of property concerns from

rising damp to cavity wall tie replacements, dry rot to

radon gas.

As a division of one of the North East’s leading plastering

contractors, BC Stewart Ltd, BCS Preservation’s ethos

focuses on providing our clients with unbeatable service

from start to finish. Our expert surveyors are on-hand

to provide an accurate diagnosis of concerns you may

have about your property and will issue a detailed yet

easy-to-understand report outlining their findings

and cost-effective recommendations for any

remedial work that may be necessary.

Our contracts manager will then arrange a

mutually convenient time for our highly

skilled technicians to carry out the works.

BCS Preservation has gained a reputation for offering a

high-quality service at unrivalled value-for-money, and

as such has carried out works across the North East of

England and further afield into the Midlands and Wales.

Our clients include private landlords and homeowners,

local authorities, architects, engineers, building

contractors and blue-chip companies.

BCS Preservation offers a range of services, designed to

protect the occupants as well as the buildings that they

live in, whilst still maintaining a connection with the

heritage and tradition set previously by BC Stewart Ltd.

The service categories are:

• Rising damp control

• Woodworm & rot treatment

• Cellar & basement waterproofing

• Resin repair systems

• Radon testing & mitigation

• Structural wall stabilisation & crack stitching

• Cavity wall tie replacement

• Air quality management

• Improving thermal efficiency

• Specialist replastering

• Full joinery services

BCS Preservation recognise that whilst there is still a

market for traditional services, demand for innovative

solutions to modern concerns and the potential

implications of these for their occupants’ health in

addition to the environment is increasing, with this

in mind we will continually develop the services

offered to ensure that we can satisfy these demands.

www.bcspreservation.co.uk | Tel: 01325 746 554 | [email protected]

Rising Damp Control

In some instances, we may recommend the installation of

an electro-osmotic system. This method involves a piece

of titanium wire being installed within the walls through

which an electric current passes. The electrical current

repels the chemical attraction that draws moisture up the

walls, therefore preventing damp from rising.

Electro-osmosis is particularly useful in older buildings

with very thick walls or walls in poor condition, as it

involves less disruption (drilling) into the structure.

When any remedial DPC is installed, it is vital that

internal walls are replastered, as the damp that has

previously risen will have carried salts from the

ground into the wall. These salts can cause ongoing

problems, for example some of them are hygro-

scopic and attract atmospheric moisture to them,

so any damp proofing that is carried out needs

to incorporate replastering to ensure that

no further symptoms of rising damp are

experienced.

The phrase ‘rising damp’ can strike fear into any

homeowner’s mind, however with accurate diagnosis and

a correctly specified solution, it does not have to be the

horror story that many dread.

Rising damp is simply the movement of groundwater up

a building’s walls by a process similar to how oil travels

up a lamp’s wick. This can occur either because the

property was built with no damp course in it (a physical

barrier to prevent the passage of water) or because the

original damp course has failed, which can occur for a

number of reasons.

Typical signs of rising damp are a tidemark on the wall

surface, loose paint or peeling wallpaper and possibly

some evidence of salts that have been carried up the wall

within the water. Our surveyors will assess any suspected

rising damp problem carefully to ensure that there isn’t

an alternative cause of the dampness, for example

condensation or a pipe leak.

If it is established that a property does have rising damp,

BCS’s surveyor will specify the installation of a new damp

course to prevent future moisture being drawn up the

walls.

In the majority of cases, this will involve a chemical

damp proof course (DPC) being injected at regular

intervals into the masonry. This chemical injection will

spread through the bricks forming a waterproof barrier

and preventing any further damp from rising.


Woodworm & Rot Treatment

Timbers in our properties are under a constant threat

of attack from insects, fungi or both. Floorboards, roof

joists, skirting boards and door frames can all be affected

by infestation of woodworm or rot, and left untreated an

attack can have devastating consequences on a building.

Woodworm is the general name given to insects that

attack timbers. There are a variety of different insects,

each preferring a different type and condition of wood

and each able to cause varying levels of damage. Over the

years, our expert surveyors have seen the whole

spectrum of infestation types likely to be encountered

in UK properties and are on hand to identify whether

active woodworm is present and the extent of the

damage that has been caused. The tell-tale signs

of a woodworm infestation are small flight holes

appearing in pieces of timber, often with a small

pile of ‘dust’ being visible around the hole.

Provided that the timbers have not been damaged to an

extent where they are no longer structurally sound, the

course of action to halt a woodworm infestation is to

treat the timbers with an insecticide. Modern low toxicity

water-based chemicals are usually sprayed onto the

timbers, but in some instances where the timber is

particularly dense, they may need to be injected or

applied as a paste.

Rot affects timbers that have become wet over a period of

time, and is classified as either ‘dry rot’ or ‘wet rot’.

Dry rot occurs when the moisture level of a piece of

timber exceeds 20% and is commonly a result of poor

building maintenance, for example ignoring a leaking

shower tray or failing to clear gutters and downpipes.

Signs of dry rot include timbers appearing to shrink or

crack, rust-coloured dust appearing on surfaces and a

musty damp odour in the property.

The first thing to tackle when dealing with dry rot is the

source of moisture. Without identifying and rectifying

this, dry rot will reoccur. Any timber that has been

affected by the rot should be removed and replaced with

new, treated timber. As dry rot has the ability to travel

through materials other than timber, a biocide will often

be applied to surrounding masonry as well. Wet rots

occur when higher levels of moisture are present, but

they cannot spread through masonry and once the source

of moisture is removed, they will cease to grow.

• Left: Example of Dry Rot effected skirting board

Accurate diagnosis of the type of rot will determine the treatment required. Where it is necessary, water-based fungicides and biocides will be applied to the affected areas. All of the products that we use are low-odour, and the treated rooms can usually be re-occupied after a matter of hours.


Basement Waterproof

The water will then be pumped away from the basement,

leaving a completely dry internal space. The capacity of

the sump pump required will be determined by our

expert surveyors according to the anticipated level of

water that will be present.

Some other methods of waterproofing simply attempt to

hold back the water from entering the property, however

using a cavity drain membrane system the water is being

actively managed away from the accommodation,

therefore it offers a greater level of protection and

reliability.

The internal wall finishes can be created using either

plasterboard dry lining or by plastering directly onto

the membrane, and the floor will be finished in a

conventional manner.

This method can also be used in newbuild

basements.

• Below: Basement after Waterproofing

Families and businesses can quickly outgrow a property,

and converting a cellar into dry, habitable accommodation

offers a cost-effective way of increasing space without

having to move. Converting this under utilised space can

also add significant value to a property.

If the space is going to be occupied as a living or working

area, it is vital that a dry, healthy environment is created.

The walls and floors of cellars are often damp as moisture

from the ground penetrates laterally through them. In

some circumstances, there may be puddles of water

present where the basement is subject to significant

hydrostatic pressure.

Over the years, various methods of waterproofing have

been introduced, with some being more successful than

others. At BCS Preservation, we favour the use of modern

cavity drain membrane systems as they are the most

sympathetic to the existing structure and provide a

reliable water management system.

Using this method, a dimpled membrane is fixed to the

walls and floors of the basement. Any water that penetrates

the structure will depressurise when it enters the air gap

behind the membrane and travel behind it into drainage

channels buried in the floor, which will guide the water to

a sump chamber.

• Below: Sump pump

ing


By using resins, much of the disruption that would

usually occur when carrying out structural repairs can be

avoided. For example, when a truss end has decayed a

repair would traditionally involve removal and

replacement of the entire truss. When resins are to be

used, however, the defective end can simply be removed

and a new section of timber be bonded onto the existing

sound part of the truss using resins.

Alternatively, a new truss end can be cast out of epoxy

resin if there is concern that the end will be subject to

water penetration in the future.

Resins can also be used to carry out repairs to concrete,

including floors, steps, and external window sills.

Epoxy resin mortars have excellent temperature,

chemical and solvent resistance and can be used inside or

out to give a totally waterproof repair.

BCS’s resin specialist has been involved with many

projects, ranging from small aesthetic restorations to

significant structural repairs.

• Left: Timber resin splice to replace decayed end

• Below: Reparing beam

At BCS Preservation we are always keen to make use of

new technologies, and over recent years the development

of specialist resins has provided an innovative method of

carrying out repairs to timbers and concrete.

When a piece of timber has become rotten, infested or

fractured, it is often only a small but structurally critical

section that needs replacing. By using resins, the

majority of the sound timber can be retained whilst only

the damaged section is replaced. This not only reduces

wastage of timber but it means that the visual impact of

the repair is kept to an absolute minimum and often

only detectable upon very close inspection.

Resin repair systems can be used to solve a wide

range of timber defects, including decayed truss

or beam ends, structural cracks - either natural

or induced, and the de-bonding of laminated

beams. They can also be used in

conjunction with imbedded steel or

carbon fibre reinforcement to upgrade

the loading capacity of beams.

Resin Repair Systems


Radon Testing & Mitigation

If high levels of the gas are detected, we are the area’s

most experienced contractors in radon remediation.

Our specialist surveyor, who has received training from

the Radon Council, will design a system based upon the

severity of the problem and the type of construction.

The mechanism by which radon enters buildings is via

advection; the gas moving from a point of higher

pressure (the ground) to a point of lower pressure

(inside the property). To prevent radon from entering

the property, a specially-calibrated fan can be used

within the building to reverse this pressure

differential or a sump can be created beneath the

building to become a lower point of pressure.

Once remedial works have been carried out, we

will always supply a set of radon detectors so

testing can be repeated to confirm that the

concentration has fallen to an acceptable

level.

Radon is a naturally occurring radioactive gas that is

emitted from the ground. It can accumulate in

properties without the occupiers knowing, as it has no

colour, taste or smell.

When exposed to high levels of radon for long periods

of time, an occupant is at risk of developing lung

cancer; official statistics estimate that over 2000

people in the UK die every year from the disease as a

result of radon exposure.

Although certain parts of the country are believed to be

at greater risk from radon due to the underlying

geology, any property in any location can contain

elevated levels.

The only way to know whether high levels of radon

are present is to place a detector in the property for a

period of time. In a standard domestic property, one

detector will be used in a ground floor living room and

one in a first floor bedroom.

The detectors are analysed in a laboratory to determine

the level of radiation they were exposed to, and a

written report detailing the results is provided.

BCS is able to supply radon test kits for homeowners

and employers, as well as short-term screening kits for

prospective buyers.

• Right: Large capacity, positive pressure unit


Structural Wall Stabilisation & Crack Stitching

Over their lifetime, buildings can be subject to

movement caused by physical or natural events. In

turn, this movement can cause cracking to the walls

of the building which, without attention can quickly

worsen and leave the property in a potentially unsafe

condition. Cracking and deterioration of masonry can

also occur as a result of the freeze/thaw cycle,

corrosion of embedded steelwork, increased loading

and due to inadequate or defective materials having

been used.

In recent years, a cost-effective remedial solution to

such problems has been developed. Through the use

of helical steel bars, a wall can be re-engineered

with little disturbance to the property and

virtually no visual impact.

Where masonry has cracked, helical bars

can be inserted into the appropriate bed

joints. This results in the tensile load of

the building being redistributed along

the masonry to minimise further

developments of the crack and

stabilise the building.

Once repointing has been carried out, there will be

little or no visual evidence of the repair.

A similar technique can be used to repair failed window

lintels quickly and neatly, a job which would otherwise

involve significant disruption to the property owner as

removal of the windows & frames would be necessary.

Other uses of our structural stabilisation techniques

include creating load-bearing masonry beams and

retaining bowed external wall.

Before any remedial work can be carried out, it is vital

that the cause of movement to the building is

identified. At BCS Preservation, our surveyors have

decades of experience in diagnosing such problems

and, where necessary, can engage a structural engineer

to carry out any required calculations or design

approvals.

• Below Right: Preparing the mortar bed joint to

receive a hidden crack stitch repair

• Below Left: Installation of a grout tie to restore

structural integrity to masonry


Cavity Wall Tie Replacement

Research carried out by the BRE estimates that of the

nine million UK properties constructed with cavity

walls, almost a quarter of these (2 million) will

suffer from wall tie corrosion or failure and will require

replacement wall ties.

Wall tie failure occurs for a number of reasons,

however the most common cause is inadequate

materials being used when the wall ties were made.

Other causes include a chemical reaction to the mortar

(for example black ash mortar) or corrosion from

driving salt-laden rain in coastal areas.

Wall ties are embedded into the outer and inner faces

of the wall. When a steel wall tie corrodes (or rusts), it

expands, causing the outer wall to crack and / or bulge.

Sometimes the roof edges can lift and cracks can be

seen internally. Alternatively, some properties have

wire ties which can disintegrate to nothing, leaving the

outer wall at risk of collapse.

If any of these signs are seen, the first step is to carry

out a comprehensive survey to determine the extent

of the problem. Our surveyors are trained to carry out

these surveys using a variety of tools, including metal

detectors to identify the location of the ties and

endoscopes to examine their condition. The survey

will also usually require a small amount of mortar to

be removed so a sample of the ties can be physically

examined.

We are able to specify and install a wide range of

different remedial wall ties (resin, mechanical or

cementitious) depending upon both the type of the

masonry and the existing condition. The replacement

ties are made from stainless steel so that repeat failure

does not occur.

An important part of wall tie replacement is to isolate

the existing ties so they do not continue to corrode and

cause structural damage.

Following any replacement wall tie work, it is

essential that the cavity is thoroughly cleaned so that

any debris from the work does not settle and bridge

the property’s damp proof course.

• Below: Wall tile replacement using

drive ties

• Below Left: Examining the condition of

wall ties using an endoscope


Air Quality Management

At BCS Preservation, we are able to install a range of

specialist air management units that will provide regular

air exchange and dramatically cut amounts of

condensation.

Positive Input Ventilation (or Positive Pressure

Ventilation) draws clean, fresh air from outside into the

property, filters it and gently diffuses it through the

property. This will force the moist, stale air to be

evacuated through weak points in the building.

The type of unit specified will depend upon the type and

size of the property involved, whether there is a loft space

and whether the incoming air requires additional heating

before being diffused throughout the property.

The units we typically install have a low energy

consumption, and many users report no increase in their

electricity bills as a result of using them. This is because

dry air requires much less energy to heat than moist air,

so heating bills are reduced as the air can be warmed

more efficiently. We are also able to install units that

contain a heat-exchanger, so the heat from the

outgoing air is retained and transferred into the

incoming air.

• Below: Example of condensation and mould growth

on a ceiling and around a window frame

A combination of our climate, building practices and

lifestyles often leads to moist, stale air being trapped

inside homes and workplaces across the country.

High humidity inside properties can lead to condensation

forming on and around windows and on colder outside

walls. This moisture can cause damage to wallpaper

and painted surfaces and lead to rot in window frames

and skirting boards. High levels of surface moisture can

also lead to unsightly and unhealthy mould growth, and

the moist air provides ideal breeding conditions for the

house dust mite.

Many respiratory conditions, including asthma, are

aggravated by poor indoor air quality but the

symptoms could easily be alleviated through the

use of air management units.

Whilst simple actions such as opening

windows after cooking or bathing and

not drying clothes indoors will reduce

the amount of moisture in the air, in

many properties this will not be

sufficient to eliminate

condensation and mould

growth.


Improving Thermal Efficiency

The cream has been formulated to line the pores of the

masonry rather than block them, so vapours can still pass

through the building fabric allowing it to ‘breathe.’

When applied the cream is white, however within 48

hours it will have penetrated deeply into the walls leaving

no discolouration, residue or sheen.

Tests carried out at two leading UK universities have

revealed that the treatment can save up to 9% of a

property’s annual heating energy that would normally

be lost.

Properties with solid walls lose around 45% of their heat

through walls. These properties are usually referred to as

‘hard to treat’ when it comes to insulation, as the options

have previously been limited to either expensive external

cladding that changes the appearance of the building, or

internal lining systems that alter the room dimensions.

BCS Preservation’s Thermalogix treatment is a unique

and inexpensive alternative that can be used to increase

the thermal efficiency of such buildings.

Applied externally as a single-coat of cream that will last

for 20 years, Thermalogix is a specially formulated cream

that penetrates deeply into the walls and reduces the

amount of moisture they can absorb. A dry wall conducts

much less heat than a saturated (wet) wall does, therefore

more heat will be retained within the property as less is

transferred out through the walls.

• Below: Applying Thermalogix


10 Evans Business Centre | Lingfield Way | Darlington | Co Durham | DL1 4QZ

Tel: 01325 746 554 | Fax: 01325 746 556

www.bcspreservation.co.uk | [email protected]

BCS Preservation Brochure

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