TECHNICAL FILE - UDDATE AUGUST 2011

Technical File Page 1

READYKIT BUILDING SYSTEM

TECHNICAL FILE

PRODUCT OF DURACASA (PTY) LTD

P.O. Box 335

Paarden Eiland

7420

TEL: +27 21 510 2233 FAX: +27 21 510 2273

E-MAIL: [email protected]

WEBSITE: www.readykit.co.za

mailto:[email protected]

http://www.readykit.co.za/


Table of contents:

1. Introduction

1.1 Duracasa, the company and product

1.2 Readykit system and details

1.3 Business plan

2. Social and economic benefits

2.1 Social

2.2 Economic

3. Construction process

3.1 Setting out

3.2 Foundations

3.3 Base plate

3.4 Floor slab

3.5 Wall panels & fixing

3.6 Wall plates and trusses

3.7 Roofing

4. Wall panels manufacturing drawings

4.1 Panel Fabrication

5. Factory

5.1 Raw materials needed

5.2 Tools and equipment needed

5.3 Health and safety

5.4 Layout


6. Tests

6.1 SABS Fire Resistance Test

6.2 SABS Structural and Rain Penetration Tests

6.3 Agrément Assessment of Thermal Performance, Energy Usage and condensation

6.4 Rational Design by HMG Structural Engineers

7. Approvals

7.1 Letter from Cape Town City Planner’s Department

7.2 Letter from Western Cape Provincial Administration

7.3 Letter from NHBRC

7.4 Letter from Standards Association of Zimbabwe

8. Photographs Previous Building


1) INTRODUCTION:

1.1 Duracasa is a South African company contracted to develop and market the Readykit

tried and tested building system that delivers cavity walled structures, at an

unparalleled delivery speed and low cost without compromising quality. Easily learnt

site construction allows for rapid skills transfer and the emergence of trained

contractors and maximum job creation.

1.2 The essentials of the patented Readykit system involves timber panels onto which is

stretched a fiberglass mesh plus a taut underlay which on site receives a 25mm

render of a mixture of building sand, cement and lime. The panels are delivered to

site including windows, door frames and an electrical layout that includes the

distribution board, stove isolator, oosterzee box and plug / switch boxes with

uprising vertical conduits in accordance to the building plan.

Technical tests over the years since first developed in 1994 have ensured that the

system is

Durable

Waterproof

Bullet resistant

60 minute fire rating

Excellent thermal protection

Condensation performance

Our Agrement Certification is now in process. Meanwhile we have received building

rights from many municipalities including Cape Town and bonds from the major banks.

Although the Readykit system was originally designed to help alleviate South

Africa’s housing shortage, experience has taught us that the system is of equal value


when applied to a wide range of buildings, such as the office block erected in Cape

Town Harbour in 1994 and a testing ward for Brooklyn Chest Hospital in 2009.

1.3 Our Business Model is to manufacture and sell building kits from our Cape Town

factory, train and license builders, and enter into franchise agreements with

entrepreneurs who wish to manufacture kits in their own area and also train and

license both established builders and emerging contractors.

Resulting in the use of ready-kit panels all over South Africa, resulting in the rapid

decrease in housing shortages and increase in skills transfer. Help Building a better

South Africa!


2) SOCIAL AND ECONOMIC BENEFITS

It need not be emphasised the fact that the ever widening gap in South Africa between

rich and poor is beginning to threaten the fabric of our society. It is imperative that

private enterprise links with government in creating self-fulfilling projects that combine

job creation with easily attainable skills transfer.

Readykit technology has already been identified as a building system ideal for Africa.

On site construction has been refined so that for a 45sq m house, a team of 7 will have the

foundation built, house erected and with a tiled roof in place in 4 days. Mechanical

plastering is faster than manual application, but the latter is more appropriate to job

creation.

The equipment needed in setting up a manufacturing facility is simple and inexpensive

(see Section 8 below) and far cheaper than required for other alternative building

systems.

Factories can be quickly established close to where construction will take place, allowing

for maximum local employment.

For the emerging franchisee and contractor our aim is to establish Readykit training

schools across the country.

The main economic benefit is a sharp growth in home industry and an increase in job

creation as well as less dependence upon job migration resulting in local employment.

Therefore the economy in the specific area will grow and hopefully flourish at an

increased rate. As acceptance of the Readykit concept spreads so will productivity

increase, which helps support the value of our currency and combat inflation, promote

ongoing affordable home ownership, lessen the poverty gap and combat crime.


People have an understandable suspicion of alternative building systems, although recent

experience is that the vast majority of failed “jerry built” houses are of 145mm block.

The track record of Duracasa shows the durability of the houses, as you will see later in

this document.

One of the hidden scourges that hit our productivity is sickness, often the result of

overcrowded tiny units that are difficult to insulate against heat and cold, and which

sweat. Under such conditions diseases such as TB thrive. It is important that we move as

quickly as possible to housing our population in healthy structures of adequate size.


3) CONSTRUCTION PROCESS

STAGE 1 – SETTING OUT

1. Remove vegetation and top soil

2. Set out the house using the centre lines of external walls as the centre lines of

foundations. Ensure all corners are square by checking the diagonal

measurements between opposing corners.

STAGE 2 – FOUNDATIONS

1. The depth of the foundations is determined by the top of the screed level which

must not be less than 150mm above the highest level of the finished ground

around the house perimeter. The trenches must therefore be 638mm below the top

of the screed level. (See figure 2 below)

Figure 1


2. Foundations consist of 450 x 200 mass concrete footings of strength 15 Mpa - the

contractor is given the choice of using stone aggregate of between 13 and 26mm

for all work.

3. A plinth wall consisting of two courses of minimum 7MPa, SABS approved

concrete blocks (190 high by 190 wide by 390 long) is built on top of the

foundation strip. Cement mortar mix ratios for laying the block plinth must be

mixed according to SABS standards of 50 kg cement to 0 – 40 litres lime

(optional) to 200 litres sand graded to SABS Standard Method 829/SANS 201. If

Builders sand already has lime incorporated, then the ratios must be adjusted

accordingly.

4. Y10 Reinforcing Bar is used to connect the footing to the block plinth. The

bottom end should be bent 90° and be 200mm long. The vertical end should be

475mm long and 75mm from the top of the plinth. The bars are to be cast in to the

footing at 800 centres to coincide with the centres of the first void of every third

block.

5. Blocks may be placed off-centre on the footing, but external block edges shall be

no closer than 75mm to the edge of the footing. Refer to figure 3.

Figure 2


6. For sloping sites, the plinth wall height may be increased to accommodate the site

conditions. If the plinth needs to be greater than 3 blocks high, then a non-

standard retaining wall to engineer's design is to be built.

Fill is then placed and compacted up to 75mm below the top of the plinth level to

allow for a 76mm surface bed which is then level with the top of the plinth.

7. If tapered cavity blocks are used then these must be laid with flat side down for all

courses (wider opening facing upwards). Blocks to be built one course at a time

and all cavities filled one course at a time. Block plinth to be filled with minimum

strength 20MPa concrete and aggregate size used will be according to builder’s

choice. Concrete must be well compacted by either rodding (manual) or vibrating.

(see Figure 4 and point 4 below).

Figure 3


8. All foundations are to be inspected and signed off by the appointed engineer and

the City Planning department before casting concrete.

The City Planning department may opt to waive this requirement but the

appointed engineer must still sign off all foundations.

STAGE 3 – BASE PLATE

1. Treated SAP timber base plates of size 76 x 38mm are placed in the centre of the

block plinth and wrapped with a minimum 250 micron Damp Proof Course(DPC).

End-to-end joints to be wrapped individually with DPC when laid.

2. Once the base plates have been accurately positioned, using temporary diagonal

timber corner stays, the plates are fastened to the plinth wall with an M10, 100mm

thunderbolt masonry screw per every 750mm. The pre-drilled holes in the base

plates must be used as guides for drilling 150mm deep holes in the block plinth

which will accommodate the thunderbolts. The pre-drilled holes are further

counterbored (25 mm diameter) to a depth of 10mm to ensure that bolts do not

protrude above the surface of the base plate. The height of the bolt head =

(0.7xM10) = 7 mm. M10 washers (external diameter = 21mm, thickness = 2mm)

are to be used with the bolts.

3. A bitumen based product is used to seal bolt holes penetrating DPC when fitting

bolts. The bolt head must not protrude above the base plate upper face.

4. Back fill and compaction of the trenches can now take place and the ground inside

the plinth walls is trimmed or filled and compacted to a level 76 mm below the

top of the plinth walls. The Engineer is to be called in at this point to test the

compaction of the ground under the surface bed.


STAGE 4 – CONCRETE SURFACE BED

1. Once the compaction of the ground has been approved, a 250 micron Damp Proof

Membrane (DPM) is placed on the compacted fill. The DPM must continue

vertically against the block plinth wall for 76mm, to the top of the plinth wall,

then horizontally along the top of the blockwork and again vertically against the

base plate so as to protrude 20mm or so above the top of the base plate, running

adjacent to the vertical portion of brickgrip wrapped around the base plate (see

figure 5 below). This will later be cut level with the top of the screed.

Figure 4

Another option is that of having the DPM continue horizontally along the top of the block

work, below the base plate, in which case a bitumen-based sealing product must be used

to seal the DPM to the DPC of the base plate. The DPM must then extend 20mm past the

base plate as in figure 6. The base plate would then be installed only once the DPM is in

place.

If the folding of the DPM leaves the top of the block work of the four corners of the

plinth wall exposed, the exposed concrete needs to be treated with Hydroflex or a similar

cement waterproofing agent. The waterproofing agent will replace the DPM at the


xposed areas and needs to overlap the DPM by at least 150mm.

Figure 5

2 If the DPM is too short to extend all the way past the base plate, the exposed

blockwork must be treated with Hydoflex or a bitumen-based or similar cement

waterproofing agent and the remaining DPM folded over onto the treated plinth

wall as in figure 7:

Figure 6

3 Cast the 76 mm thick concrete floor slab, using a 20MPa concrete and screed off

level with the top of the plinth wall. The concrete for the floor slab is to be of a

suitable slump and consistency for proper compaction, tamping and levelling.


4 Once the surface bed has been cast, tamped off level and has cured for 24 hours,

the floor screed can be applied so as to finish level with the top of the base plate.

STAGE 5 – WALL PANELS

The wall panels are constructed in the factory in accordance to the specific panel

specifications. The fabrication is described later in the file. Additionally all the

information on the factory is also later in the technical file.


STAGE 6 – WALL PANEL INSTALLATION

Method for fixing panels to each other and the base plate

Please find below the directive for fixing Duramesh panels to each other as well as to the

base plate.

Tools and Materials required:

Hurricane Clips: Timbalok

or equivalent

Nails: Clout nails with anti-

corrosion treatment/coating

Claw Hammer


Tools and Materials required:

Staple Gun

Panel Alignment Device

Spirit Level

Four Inch Nails


In-line Panel Fixing Required:

Hurricane clips

Hammer

Staples & staple gun


Spirit level

Four inch nails

Precautions: Ensure that the panels are lined upright at 90 degrees using spirit level. If

necessary start with bracing on the first two panels to ensure accurate alignment of the

panels. The use of long 4 inch nails may also help to sure up the panels with one anther

and the base plate. Start with panel one and work around the building n both directions

to ensure speed and efficiency.

NOTE: If care is taken with the erection of the panels to ensure straightness and

plumb, it saves an enormous amount of time, effort and money later when it comes to

plastering, fitting skirting, ceilings, facias, tiling etc.

All panels must be checked after to ensure fixing and alignment.

Three hurricane clips and respective

number of clout nails used to fix the

panels to the base plate. Along the

bottom of the panels.

Four additional hurricane clips per

panel used to fix the panel to each

other.

Each clip positioned roughly one third

(600-800 mm) from the top and the

bottoms of the panels respectively.


In-line Panel Fixing Required:

Hurricane clips

Hammer

Staples & staple gun


Spirit level

Four inch nails

Two on the inside and two on the

outside of the panels.

Starting in the corner ensures the

accuracy of alignment of the panels.

Start fixing panels in both directions

using teams of three carpenters. You

may use the four inch nails to help fix

panels and base plate together.

The internal and external panels are

also skew-screwed to the base plate,

each other along their lengths (with 4

M6, 75mm coach screws per length,

but only from the inside face). Screws

are inserted in holes that have been

pre-drilled in the factory.


STAGE 7 – WALL PLATES

1. Wall plates of 76 x 38mm are secured to the top of all wall panels with galvanised

clout nails at 1m intervals at panel uprights. A second layer of wall plates is nailed to

the wall plates on the external panels only, using galvanised clout nails, also at 1m

intervals as shown:

Figure 11 Figure 12

Prior to nailing the wall plates in position, 680mm lengths of light gauge roof bracing are

inserted between panel top and wall plate at 750mm centres. The bracing will be used to

fix the trusses to the wall plate and the wall panels where the trusses do not coincide with

a panel upright i.e. every 1.5m.

Where the trusses do coincide with the panel uprights (at every third upright) the bracing

must go from the upright across the top of the “truss-fill-in” panel down the inside. The

brace is to overlap the panel upright by at least 150mm on either side of the panel, with a

total length of approximately 680mm.

All bracing is to be secured into the upright by at least 2 “serated” nails at 100mm

centres.

All corners where walls are longer than 1m are to receive a 38mm thick timber bracing of

1.41m which is set at 45˚ and forms part of the second wall plate layer. The bracing is


fixed onto the first wall plate layer (similar to the second wall plate layer), 1m from the

corner, as illustrated in Figure 13 and Figure 14:

Figure 13

Figure 14

2. The roofs are all designed and erected on site by a qualified roofing sub-

contractor with the appropriate A19 certification. The roofs are to be braced

internally so as to act as horizontal diaphragms that carry transverse wind loads on the

walls to the orthogonal walls which act as shear walls.

3. Each gable overhang must be one tile wide.


4. Roof eaves must have an overhang of two tiles each side subject to the distance

between houses which may require that the eave overhang be shortened.

5. Trusses, which are exposed to the elements, are treated with creosote.or similar

wood preservative.

STAGE 8 – ROOFING

1. Readykit system is compatible to any roofing system.

2. The pitched tile roof is the recommended system to use with the Readykit panels.

This will require the double wall plate and the standard purlin and batten process.

Tiles or sheeting are done in accordance with the SANS 1082.

3. If an iron or lightweight roof sheeting used the trusses must be at 1m centres and

can have a single wall plate.

4. Roof trusses must be braced across and fixed with hurricane clips fully nailed.


4) WALL PANEL MANUFACTURING

PANEL FABRICATION

1. The system involves the fabrication of wall panels in a factory. Panels have the

window frames, door frames and electrical conduit, switch and plug boxes

installed in the factory this also includes the J2 shallow connection box and

distribution board. Although fabrication is simple, the process requires precise

management of the numbering of each panel so that the correct house is sent to

site.

2. Panels are made of SA Pine of dimension 76mm x 38mm. All panels have an

external width of exactly 1m, or 1.5m, or 2m, and an overall height of 2.476m.

This height can vary according to specifications for higher ceilings and may be

increased up to 3.076m high.

3. As per figure 8 above, each panel comprises three long uprights of 2.4m and a top

and bottom horizontal member nailed to each end plus horizontal bracing at about

260mm intervals. Steel jigs are made from welding angle iron about 30mm x

30mm with the flat side inwards and used to construct the panels to exact size.

4. Window frames are inserted and nailed into position leaving 25mm protruding

beyond the panel timber. A Sondor closed cell foam strip is compressed between

the panel and the window frame.

5. Door frames are similarly nailed into position..All wire nails to be 75mm long.

The following description sets out the manufacturing procedure of door and

window panels


PROCEDURE FOR DOOR AND WINDOW PANELS

1. The full width of the wall panels (and thus the window and door reveals) is

126mm (76 + 25 + 25).

2. In order to increase the overall width of the frames to 126mm to match the plaster

reveals, sub-frames are attached to the window frames.

3. These composite frames are installed into the wall panels such that the window

frames project 25mm beyond the outer faces of the timber wall panels and the

sub-frames project 25mm beyond the inner faces of the timber wall panels. A

116mm x 5mm Sondor closed-cell foam strip (SPX 33 PSA) is glued to the outer

perimeter of the composite frame which is then fitted into the framed opening in

the wall panel. The wall panel opening is 2,5mm wider than the composite frame,

(i.e. 2.5mm on each side of the window), resulting in a 50% compression of the

closed-cell foam strip. This ensures a good waterproof seal between window

frame and wall panel. When the walls are plastered, the protruding frames

provide a template against which to plaster and the Sondor strips form flexible

edges to allow for movement between window or door frames and plaster.


4. Doors are similarly treated.

Figure 9

5. External open-in doors must be fitted with a weather bar similar to the one shown,

attached to the outside of the door:

Figure 70


6. All wall panels have a sheet of Marley underlay sheeting on both faces of the

panels. The next step is to affix the Marley sheeting to both sides of the panel

with the staple gun. The sheeting then serves as a waterproofing layer as well as

for strength and to plaster on.

7. The Marley sheeting is fixed onto the Noggins via 1010 Staples (10mm in length,

and 10mm crown width) and pneumatic staple guns, as used in the upholstering

industry. The staple guns are powered by a small compressor. Two additional

strips of mesh (76mm wide) are fixed to the left side of a Panel and serves to

overlap the junction with adjacent panels.

8. Those panels that are to receive electrical conduits will have 25mm holes to allow

the conduit to protrude about 150mm above the panel and go down low enough to

the light switch, external light fitting, or wall plug as per the house design. Four

short conduits are required near the top of the panel that will contain the

distribution board, J2 shallow connections box.

9. Once completed and quality checked, each panel is numbered for according to

position house and placement in the wall, to ensure for easy erection on site.


5) FACTORY DOCUMENTATION

This document contains all necessary information to start manufacturing of

Readykit panels. It furthermore contains requirements for all the tools, materials,

health and safety, manufacturing process and proposed layout necessary to start up

a factory and produce panels.

All the materials and tools listed are examples taken from the factory or a better

alternative is proposed. Any alternatives are used at your own discretion.

Raw Materials:

The following table of materials does not contain recommended quantitative, since

this is dependent on the rate of supply versus consumption which is unknown. The

rule for defining the raw material buffers is that the buffer must be equal to the

maximum estimated consumption within the reliable time to replenish the buffer.


Material: Description: Sizes/purpose:

Timber Tanalith Treated Grade 5 SA

Pine, Dried and Sawn

38 x 76mm

Noggins

Tanalith Treated Grade 5 Sa

Pine, Dried and Sawn

16 (minimum) x 76mm

Door Frames Order form supplier Open-in

door frame 895 x 2116mm or

open-out door frame 895 x

2103mm for external doors.

Internal doors 870 x 2050mm

Window Frames; Swartland Customized

Winsters for Readykit panels

or alternatively WINKLIK

from Cipco (Pty) Ltd.

600mm (615 x 920mm)

900mm (920 x 920mm)

1200mm (1160 x 920mm)

Meranti wood from a supplier 70 x 22 x 3000mm planed

meranti – is used on top of

doorframe to increase size

Marley Underlay Marley sheet waterproofing

tile membrane

Standard roll of underlay

Electrical Conduit piping UPVC 25mm thick/diameter

Electrical outlet box Standard box 105 x 105 x 40 mm

Distribution Board Mod- 12- econ-5 Only one size with that type

J2 shallow connection box Standard box 105 x 105 x 40 mm or

equivalent

Staples Standard staples for staple gun 10/13/16mm long staples



Nails Standard for nail gun you have Box details of T38 & T64

Timber treatment Maxi Care – mahogany (or

equivalent)

5 l

Bitumen Paint Super Laykold bitumen black

paint as a waterproofing

system

Used on base plates only not

needed for the panels

Silicon Standard Black silicon from

penny pinchers

For waterproofing corners of

walls In tube( only one size) to

fit sealant gun

Waterproofing Rubber foam from Sondor

Industries

115 x 5 mm

Masking tape Standard 24mm- to number base plates

on top of the bitumen

Spray paint Any standard paint – Red or

Black, or both

Used to mark the panels

Stencils for numbering Custom made or bought

numbers 1 to 9, to number

panels

Made out of A5/A4 sizes card

Timber/steel Storage bins/shelves Hand made storage bins to

store the cut timber pieces.

Extra shelves or tool racks if

necessary



Glue Alcolin, Water based glue

(wood glue)

Alcohol water proofing ultra

water based glue

Screws Drywall screws 9 x 30 mm


Tools:

Tool

Description

Size/designation: Minimum

Recommended

QTY

Recommended

brand (reliable

products):

Picture

Pneumatic

Nail Guns

Standard

compressed air nail

gun

Fit nails 22-64mm

2 Testo – t-type


Pneumatic

Staple Guns

Standard air stapler

Fit staples 6 –

22mm

2 Raco air tools

6. 22mm s - type

Air

Compressor

Standard

1 No

recommendation


Compressor

piping

Standard – to fit

your specific

compressor and

nail/ staple gun

2 pipes +

Connection to

use two tools at

once

No

recommendation

Radial Arm

Saw

Minimum blade size

of 300mm

1 Dewalt


Cross cut

Hand saw

700 x 525 mm or

bigger

1

Stanley

G clamps 4 – 7+ adjustable

clamps

4 Irwin

Sash clamps 2000mm long

4 Sealey


Rubber

mallets

Minimum size of

200mm long

1 No

recommendation

Hand Drills Standard electric

drill

1 Makita


Flat steel

wood drill

bit

Standard set – steel

1 set – most

important a

25mm bit

Most likely come

with the drill or

buy the same

brand as drill

Craft knife Standard 2 Stanley

Side

cutter/Cuttin

g pliers or

combination

pliers

Standard 1 Stanley


Square

measure

Standard (500 and

over)

1 Stanley

Claw hammer

Standard - used

more for taking

nails out

2 Any

Tables or

pine boards

2440 x

1220working tables

2 No

recommendation

(good quality

required though)


Spindles for

Duramesh

and

Undertile

membrane

Minimum of

2000mm

2 – 1 for each No

recommendation

Toggle

clamps

Minimum of 4

inches

6 Irwin/sealey


Measuring

tape

2 x 5m 2 Stanley

X amount of

Leads/cords

Dependent on

factory size

Dependant on

layout and plug

points

No

recommendation


Circular

table saw

Minimum of

300mm blade

1 Dewalt

Drill press Standard

With a 13mm

capacity chuck

1 Dewalt


Sealant gun Standard 1 Stanely

Screw driver

set

Star and flat for

work on the factory

machinery

One star and flat

or ideally a set

Bosch

Small tool Set as required


Health and safety Equipment and Requirements:

The health and safety in any factory is very important and of a high priority. The

following merely serve as a few guidelines. It is the franchisee’s responsibility to ensure

that they are aware of and meet all the health and safety requirements in terms of the law.

Appoint a safety officer for the factory. Such a person should preferably have

completed a first aid course.

A dust mask and a pair of safety goggles are to be issued to all workers, as well as

suitable clothing, i.e. overalls.

Suitable shoes, all factory workers must have closed shoes, preferably safety

boots.

All equipment and tools must have a suitable area in which to be stored, as

anything left lying around will be a health and safety hazard. There must be

suitable working area for each table/machine etc. as to ensure people are not

working on top of each other.

Demarcate safety zones around equipment

Post safety signs in suitable places

Ensure all equipment is kept in a good state of repair

Ensure all workers are properly trained to use their equipment safely – especially

circular saws – these units can very easily maim and/or kill workers! Be

particularly aware that loose clothing / long hair etc can become entangled in

rotating equipment and cause serious harm.

Gloves are recommended if rough wood (un-planed) is handled

Be careful when stacking / storing panels so as not to create a safety hazard (e.g.

toppling).

Fire safety requirements and standards have to be met in terms of the building.

Furthermore it is a requirement to have a fire hose and fire extinguisher – dry

powder serviced regularly. The local fire station can be a good source of

guidance and training.

There must be a well stocked first aid kit available and accessible in case of an

emergency/accident.


Factory Layout

In order to ensure the best productivity and working environment with the best flow it is

important to ensure the factory layout is set out well. Therefore knowing the process of

what is going to happen in the factory is very important. All consideration in terms of

storage and movement of machinery and materials must be taken into account before the

layout is completed.

The process of the panel manufacturing needs to be considered. The wood is ordered in

and the radial/circle saw is used to cut the right lengths, this wood is then stored in the

bins. This means most of the work is then done on the jigs and the tables. The wood is

then moved from the bins to the jigs to start assembly. Once the frame construction is

complete, the panels move across to the wrapping tables. This is where the panels get

completed. The mesh underlay and any other material is added. Also to be considered is

where the tools are to be stored as they need to be in close proximity of the applicable

table. The timber door and window frames must also be situated close to the jigs, for

when built into the panels.

The numbering of the panels, using the spray paint should be done in a well ventilated

area.

It may be decided to produce panel to stock, in which case a stock room will be required

and the numbering of the panels will take place just prior to shipping.

A recommend factory layout is provided below.



7) QUALITY TESTS

The Quality Tests follows in the following order:

SABS Fire Resistance Test

SABS Structural and Rain Penetration Tests

Agrément Assessment of Thermal Performance, Energy Usage and Condensation

Rational Design by HMG Structural Engineers





















DURACASA – READYKIT HOUSING – RATIONAL DESIGN

DESIGN OF BASIC UNIT

Basis of design

1. Internal walls not taken into account for lateral loads to allow for complete flexibility.

2. Roof to be designed to act as horizontal diaphragm so that lateral loads on a 6m x 2,5m wall panel

will be equally shared between foundation and roof and resisted by sheer capacity of side walls.

3. Wall panels orthogonal to the lateral loads to be designed to span foundation-to-roof (i.e. vertical

spanning)

Wind loads – SABS 0160 (table 5)

Assume Ter. Category = 2

Element class = B

Basic wind speed = 40m/s

Site altitude = 0 m A.S.L

Building height = < 5m

Wind speed multiplier kz = 0,92


Therefore Vz = 0.92 x 40 = 36,8

qz = kp.v² where kp = 0,6 (0 m ASL)

qz = 0,6 x (36,8)² ÷ 10³ kN/m²

= 0,812 Kpa

Cpe (wall) = 0,7 or –0,2 Cpi = 0,0 or –0,3 Cpe (roof) = -0,9

Check wall panel for vertical spanning (excluding reinforced plaster)

Because of 25mm reinforced plaster attached to both sides of panel, the wind load will be equally shared

between the 3 vertical members.

Wind pressure on panel

= (Cpe + Cpi) x qz = 1,0 x 0,812 = 0,812 Kpa

Moment = 0,812 x 1,0 x (2,5)² = 0,634 kNm

8

Resistance

Permissible stress in timber = fb x k1 x k2 (k1 = duration of load)


(k2 = sharing)

k1 = Wd + Ww

Cfd + Cfi Wi

But dead load not considered

Therefore k1 = Ww = 1 = 1 = 1,5

Cfi. Ww Cfi 0,66

k2 = 1,15 (Sharing due to spacing < 0,6m)

Therefore: For grade 5 timber:

Permissible stress fb = 5,0 x 1,5 x 1,15

= 8,6 Mpa

Resistance moment = Z x fb -6

= 38 x 3 x (76)² x 8,6 x 10 = 0,944 kNm

6 (< 0,634) Therefore Ok

Consider racking of shear walls


Wr = Mass of half roof

Ww = Mass of wall

F = 0,812 x 2,5 x 6,0 = 3,04 KN

2 2

Mass of roof : (minimum)

A Roof sheeting = 0,08kPa x 3,0 = 0,240 kN/m

B Rafters = 5,0 x 0,22 x 0,038 x 3,0 = 0,125 kN/m

C Purlins = 5,0 x 0,076 x 0,05 x 1 = 0,016 kN/m

1,2

______

0,38 kV/m

Therefore Wr = 0,38 x 6,0 = 2,28kw

Mass of wall :

a) frame = 5,0 x 0,038 x 0,076 x ((2,5 x 3) + (1,0 x 6)) = 0,195 KN/m

b) plaster = 24 x 0,02 x 2 x 2,5 = 2,4 kw/m

2,59 kn/m


Therefore Ww = 2,59 x 6,0 = 15,57kn

OTM = 3,04 x 2,5 = 7,6 knm

RM = (15,57 +2,28) x 3,0 = 53,55 knm

Therefore OK against racking

Principle Tensile Force (diagonal) = 3,04 x 1

Cos x

(Where x = arc tan 2,5 = 22,61º)

6,0

Therefore Principle tensile force = 3,04 x 1 = 3,3kn

Cos 22,61º

Tension in say 100 wide band of plaster/mesh each side

= 3 300 = 16,5 N/mm

2 x 100

Duramesh R080 strength = 160 N/cm or 16N/mm

Duramesh 155 strength = 360 N/cm or 36N/mm

Therefore either will have sufficient tensile strength – OK

Roof Uplift:

Wind uplift = (Cpe + 0,2) qz (allowance for dominant opening on windward wall

= (0,9 + 0,2) x qz

= 1,1 x 0,812 = 0,893 kPa

Therefore force on wall =0,893 x 3,0 = 2,68 kN/m

From page 3, Mass of (roof + wall ) = Wr + Ww =

2 = 2,28 + 15,57 = 17,85 kN/m

Therefore Mass of wall = 17,85 = 6,66 = F.O.S. (uplift)

Uplift 2,68


Total length of timber in truss

= 6,0 + (6,0 x 1 ) + 1,5 + 1,5 + 0,35 = 15,44

cos 10º

Say 16m

Roof Trusses

@ 1000 c/c

W = Sheeting 0,08 kPa = 0,08 kN/m

Purlins 0,076, x 0,05 x 1,0 x 5 = 0,019 kN/m

Trusses 0,114 x 0,038 x 16 x 5 = 0,347 kN/m

(Ceiling) = 0,150 kN/m

L.L = 0,3 = 0,30

0,816 kN/m (or kPa)

Heel joint - F: 0,816 x 3,0 x 1 = 14,097 kN

Sin 10º

Stress in rafter = 14097 = 3,25 Mpa = σc


114 x 38

L/b = 1000 = 26,3 Therefore Pc = 3,64 Mpa = therefore OK

38

Foundation (See construction manual)

Alternatively raft foundation as follows:


STEP 1 450 X 450 X 50 CONCRETE PAVING SLABS

STACKED TOSUIT LEVELS PLACED AT EACH

CORNER OF 6M X 6M UNIT TO SUPPORT

NAILED-TOGETHER FRAMES

STEP 2 ERECT FRAMES

STEP 3 DIG TRENCH AND LEVEL OFF GROUND FOR

CASTING SLAB

STEP 4 WRAP SOLE PLATES WITH DPC

STEP 5 CAST SLAB AND THICKENING TOGETHER

Check on wall panels: (2,7m high)

From original calcs page 2 qz = 0,812

Cpe + Cpi = 1,0


M = 1m0 x 0,812 x (2,7)² = 0,7399 kNm

8

6

fb = 0,7399 x 10 x 6 = 6,74 Mpa

3, (76)² x 38

Load duration coefficient =0,66 (wind load)

Therefore k1 = Wo + Ww

1,0Wo + 0,66 Ww

= Ww

0,66Ww (DL = 0 laterally)

= 1,51

Load sharing factor kz = 1,15

Therefore Pb = 5,0 x 1,5 x 1,15 = 8,6 MPa for grade 5

= both of these are greater


than 6,74 therefore OK

= 4,0 x 1,5 x 1,15 = 6,9 MPa for grade 4

Therefore No shear connection required

Roof x Roof support (Cement tiles on battens on trusses)

All roofs are to be designed and erected on site by a qualified roofing contractor with the

appropriate A19 certification. The roofs are to be braced internally so as to act as

horizontal diaphragms that carry transverse wind loads on the walls to the orthogonal

walls, which act as shear walls

This clause is included in the Housing Construction Manual (submitted herewith and to be included in

tender documents for builders wishing to be trained and certified as approved erectors of the houses)

Check wall panels for truss loads:

Trusses at 750 c/c

Span = 6,15m


Worst case is when truss is mid span between panel edge and panel centre post (As A above)

NOTE! INTERNAL WALLS ARE NOT LOAD-BEARING

Roof loads: (Timber density = 5 kN/m³)

1 Roof tiles = 0,49 kPa

2 Battens (0,038)² x 5 x 1 = 0,029 kPa

0,25

3 Trusses 0,114 x 0,038 x 3,0 x 5 x 1 = 0,087 kPa

0,75

4 Ceiling = 0,15 kPa

5 Superimposed Load = 0,30 kPa Roof bed 1,056 kPa

= 1,056 kPa

Truss Span = 6,15 m

Therefore Point load on wall plate = 6,15 x 0, x 1,056 = 2,435 kN

2

Total DL = 0,756 kPa

Total LL = 0,300 kPa


Pb = 5,0 x k1 (Where k1 = 0,756 + 0,3 = 1,103)

0,756 + (0,67 x 0,3

Therefore Pb = 5,0 x 1,103 = 5,517 MPa

-6

Therefore MR = 5,517 x (38)² x 75 x 10 = 0,0996 KNm

(75 x 38) 6

MR = 5,517 x (50)² x 75 x 10 = 0,172 kNm

(75 x 50) 6

From Prokon: (See attached Prokon output pages 01 – 06)

75 x 50 wall plate is continuous @ A and B

75 x 38 top plate is continuous @ A and simply supported @ B


From Prokon Analysis (Pages 01 – 06, attached)

50 x 75 wall plate moments

Moment (wall plate) = 0,16 kNm (less than 0,172 kNm therefore OK)

Moment (top plate) = 0,06 kNm (less than 0,0996 kNm therefore OK)

Consider uplift

From page 5 uplift pressure = 0,893 kPa

DL = 0,756 kPa

Nett uplift = 0,137 kPa

Therefore nett uplift at truss end = 0,137 x 0,75 x 6,15/2

= 0,316 kN

Capacity of M10 coach screw (75 long) in tension

= 0,74 KN (for 25 penetration)


Therefore if coach screws @ 750% then FOS = 0,74 = 2,34 (OK)

0,316


Use following:

Treatment of door and window openings


Lintol moment = 2,435 x 1,0/4 = 0,6088 kNm

Fb = 0,6088 x 10 x 6 = 3,748 Mpa (OK)

(114)² x 75

Check side walls as shear walls

Consider the wall panels acting as shear walls


Wind force P1 = 0,893 x 0,7 x 3,0 x 2,5 = 2,3 kN

2

Wind force P2 = 0,893 x 0,2 x 3,0 x 2,5 = 0,67 kN

2

P1 + P2 = 2,97 kN

2,97 8 (per panel)


Mass of each panel = 2,59kN (from page 3)

Moms about A (Per panel)

OTM = 2,97 x 2,5 = 0,928 kNm

8

RM = (2,32 + 2,59) x 0,5 (ignoring F)

= 2,455

Therefore ignoring shear resistance between panels (F),

F.O.S = 2,455 = 2,645 (OK)

0,928

Therefore the mass of roof and individual wall panels is sufficient to overcome racking force of each panel

due to horizontal wind load.

Therefore the panel connections through nailing need only be nominal.


In addition to this, there is a certain amount of shear connection between panels through the mesh-

reinforced plaster.

Therefore shear walls are sufficiently braced.

Each individual panel is stiffly braced by the diaphragm effect of the mesh-reinforced plaster connected to

the timber frame.

In summary:

The above calculations prove the stability of the system under dead, live and wind loading.

The Housing Construction manual provides additional information regarding the erection procedure, which

is to be strictly adhered to, and monitored by an appointed professional engineer,

The roof is to be designed and constructed by a suitable A19 certified roofing company and braced to form

a diaphragm between walls.

The Housing Construction Manual is to be read as part of this rational design.


8) APPROVALS

The approval documents follows in the following order

Letter from Cape Town City Planner’s Department

Letter from Western Cape Provincial Administation

Letter from NHBRC

Letter from Standards Association of Zimbabwe






9) PREVIOUS BUILDINGS

1994: 8 Mqaai St, Makana Sq, Langa, Cape Town

Erected after 2 days

Completed – 17 days later

1995: 9 Protea Circle, Ocean View

First day

Completed – 22 days later

1994: Offices for Portnet Container Port, Cape Town Harbour


2005: Show house, Erf 52808, Weltevreden, Parkway, Highlands Village, Cape Town

2 Bedrooms, 52m2 plus car port


1994: 17 Louis Trichardt street, Worcester

Plastering

Completed

1995: House of SACLA health worker – 573 Z Memani Ave KTC

After 3 Days – Erected and roofed

Completed – 3 weeks later

TECHNICAL FILE - UDDATE AUGUST 2011

Documents