Practical Building Guide

8/6/2019 Practical Building Guide

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Practical Building Guide Tips and Hints on Building with Durisol

Contents

1. Safety Equipment required

2. Tools required to build with Durisol3. Stacking and storing Durisol blocks on site4. Foundations accuracy reinforcing5. Reinforcement6. Setting out7. Laying the first course corners, modifying units8. How to cut Durisol wall forms9. The correct way to stack10.Pouring with concrete slump11.Openings, installing lintels12.Internal walls to the external envelope

13.Installing services installing conduit in main wall

14.Intermediate Floors and Wall plate15.General tips and advice


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1. Safety Equipment requiredWe strongly recommend that when handling Durisol that as a minimum, safety boots, gloves and

overall are worn and when wallforms are being modified, safety glasses should also be used.

This is in addition to any standard on-site health and safety requirements

2. Tools and consumables required to build with Durisol

There are no special tools required when building with Durisol wallforms and the following would be

a typical requirement:

A chalk line A level, preferably over 2m in length , and a short level of 450mm A hand held battery/power circular wood saw fitted with a depth gauge or alligator saw. A hammer drill Hole saw, 3 and to the size that any pipes/ducts need to pass through the wallforms A Bricklayers trowel Foam gun Tape measure Wooden or rubber mallet Course threaded screws Wedges for levelling ( 1-5mm thick )

3. Stacking and storing Durisol walling on site

Durisol wallforms are delivered in pack sizes approx 1m x 1m x 1.2m. They form their ownpallet so caution should be used unloading and moving the packs to avoid damaging the

bottom layer


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The packs must be stacked on level ground and should not more than 3 packs high There is no requirement to cover the packs Building Multi storey buildings - To minimise the use of scaffolding, multi storey buildings

can be build to 1st floor level; then having installed the floor, pallets can be loaded onto thefloor and building can continue from the inside of the building. Guard rails may be

necessary.

4. FoundationsFoundations for Durisol wall Systems are no different to other wall systems and can be built on bothstrip and raft foundations.

Because Durisol is dry stacked, getting foundations as level as possible is important. The aim should

be to get the foundations within an accuracy of 5mm. If this is impossible, the first course can be laid

into mortar to ensure that it is level. The mortar mix is the same as if laying concrete blocks. It is

worth spending time on the first course as this will save time later.

In the case of a stepped foundation the bottom layer of wallforms might need to be modified to

create a level course i.e. a step of 150mm will need to have 100mm cut off the wallforms

horizontally, as illustrated

below

5. ReinforcementReinforcing bars are not always needed in concrete!


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If required, the steel reinforcing tails can be formed in the foundations by various methods. The

amount of reinforcing required will depend on the design/height of the building. Where the unit has

been cut, as in the illustration above, ensure that the reinforcing bar passes through the cut block

and into the whole block.

Placing the rebar - Method 1: Whilst the foundation concrete is still wet, measure out and inset the

bars to correspond with the concrete fill area in a Durisol wallform

Method 2: When the foundation concrete is set, mark out the position of the wall, drill a hole in the

foundation and insert the bars either as a friction fit or with a resin bonding agent.

Rebar Requirement- Durisol UK cannot specify your rebar requirement; it is the responsibilityof the structural engineer to make up a schedule.

6. Marking out The walls should be marked out on the foundations prior to commencing stacking the

individual wallform units. This is best done with a chalk line and then the corners sprayed to

mark them clearly.

Mark all the door openings. A 2nd line 20mm outside the wallform units line can mark the positions of all window

opening as reference points. This is done to assist with the technique of building from the

inside out and if possible, stack all the packs of wallforms needed to complete the first

storey, within the foundation boundaries.

7. Laying the first layer of wallformsREMEMBER TO ENSURE THE WALLING UNITS ARE ALWAYS LAID SO THAT THE INSULATIONIS ON THE OUTSIDE OF THE BUILDING.

The corner units should be laid first, working towards the middle. Note the corner units will need notches cut into the internal side of the form 50mm deep

both top and bottom to line up with the notch on a standard form


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This has two purposes; to allow the flow of concrete around the corners and also to providea position for any necessary horizontal re bar to be located.

Face blocks should be used at door and window openings. For curves, the forms can be modified by cutting; the same method as used with tradition

concrete blocks, and can be held in place using foam as below-


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8. How to cut /core drill Durisol wallforms

If wallforms need to be modified, they can be cut with standard wood cutting tools includinga hand saw. Experience has shown that the best method is using a hand held circular sawwith a wood blade. It is advisable to keep a blade just for this job. Other methods include a

diamond blade on a petrol stone cutting saw, chain or alligator saw.

It is better to modify two forms rather than to try to insert less than 120mm long in onepiece.

It is possible to chase out the Durisol material for services or conduit to be installed. A handheld circular saw can be used with the depth gauge set at least 1mm less than the Durisol

material thickness or a specialist wall chasing tool. Once the two cuts are made, it is very

easy to remove the Durisol material with a cold chisel.

Wallforms can be core drilled with traditional saw bladed hole saws

9. The correct way to stack Durisol wallforms should be dry stacked by overlapping half a block each layer stretcher

bond (the same as with laying concrete blocks or bricks). They should not be built in

columns as this compromises the concrete flow and strength of a finished Durisol wall.Stand-alone columns can be built in certain circumstances.


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The wall should be checked for line & level before the concrete pour and should there beany deviation, this can be corrected by inserting wood/plastic wedges to level the units.

Any gaps that are left that require a modified unit, should be staggered on each course andif possible avoid modifying corner/face blocks except for 365 forms.

The Rockwool/Knauf insulation can also be easily cut with a wood saw. All waste Durisol material can be returned to the factory for recycling including mineral wool

insulation.

10. Pouring Concrete Concrete strength will depend on the design and height of the building. Concrete used should an aggregate size of 10mm as this helps the flow through the

wallforms. The slump should be between 180-220mm is important to achieving a void free

pour.

The concrete can be placed in many different ways, from the simple bucket by hand, aconcrete skip from a crane or machine to a concrete pump. If using a mechanical method a

150mm discharge pipe is ideal.

When pouring, ensure no spills occur, cleaning any that do, paying particular attention tothe tops of the wallforms to ensure they remain totally clean.

When pouring, if more wallforms are to be stacked on top, leave approx 100mm from thetop of the form empty to ensure the next pour keys into the previous one .

Ensure that the concrete is poured in a controlled way and not from a great height.

11. Openings - Installing LintelsHow to create openings: Durisol forms can be stacked in a way that creates insitu lintels

over openings saving the cost of bought in lintels.

To create the lintel former, one end of the face unit and the internal web

should be cut out to create a U shape as shown.

The vertical walls of standard door and window openings are also created

using face units.


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When the openings are formed, a temporary prop is required to support the lintel section during

pouring and this can be screwed directly to the other walling units.

Horizontal reinforcement will be required as specified by the structural engineer depending on

span and loading.

To create round openings, stack the wall units, scribe the outline of the opening

onto the units. Dismantle the units, cut them and then restack. Use a temporary

shutter to ensure the concrete does not come out of the forms; this can be attached

by screws directly into the forms.


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12. Internal Walls - How to join internal walls to the external wallAn internal Durisol wall is best built at the same time to make it integral to the external structural

envelope. The easiest and best way is to cut a channel into the external form the same width as the

concrete core (120mm for a D170 unit), to allow the concrete to have a flow channel. This can be

done after the external wall is stacked using a saw. A core drill at least 125mm in size could also be

used.

Steel bars drilled into an existing external wall would be sufficient to join an internal wall built at a

later date.

Other standard walling systems can also easily be used with Durisol.

13. Installing services in Durisol wallform wallsIf services are required to pass through the wall, install a duct prior to pouring.

Services can be placed vertically into the concrete void as long as they do not take up more than 25%

the void, and should be installed within conduit.

Prior to internal plastering, the Durisol material can be chased out after pouring using either a wall

chaser or a powered circular saw with a depth gauge; the gauge being set at slightly less than the

thickness of the Durisol woodcrete and then cold chiselled out.


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14. Floor systems and wall plateStandard flooring systems can easily be used with Durisol.

To incorporate block and beam floors or insitu concrete poured floors, the walling units can be

modified to suit the required floor height by cutting an L shape leaving the insulation as shown

below.


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The concrete is poured and the beams sit against the insulation. For insitu concrete floors, the

vertical wall reinforcement will be bent to link in with the floor rebar.

For standard timber floors, fully stack the walling units and complete the concrete pour. Then fix a

wall plate directly into through the Durisol into the concrete core with the necessary fixing.

Alternatively see our suspended floor detail.Suspended floor detail.pdf

Wall plate to support roof- The wall plate is fixed to the top of the poured concrete bymeans of screws into the concrete core with strapping also be screwed into the wall .

15. General tips and advise

Anything that will cut wood will cut Durisol wallforms. Accuracy on the 1st course helps to ensure an easy build. Forms can easily be modified to suit site or design requirements. Cut wall units can be held in place with expanding foam prior to pouring especially on

curves.

Ensure wallform faces and edges are clean prior to stacking, as even slight contaminationcan compromise a level stack.

If forms do start to go out of line or level, use wedges to correct.
http://c/Users/laura/AppData/Local/Temp/Technical/Details/Suspended%20floor%20detail.pdfhttp://c/Users/laura/AppData/Local/Temp/Technical/Details/Suspended%20floor%20detail.pdfhttp://c/Users/laura/AppData/Local/Temp/Technical/Details/Suspended%20floor%20detail.pdfhttp://c/Users/laura/AppData/Local/Temp/Technical/Details/Suspended%20floor%20detail.pdf


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Remember the insulation sits on the outside of external walls Get in the habit of stacking from the inside out If a form is cut incorrectly or has been damaged, use scrap wood to cover holes prior to

pouring, there is no need to discard.

To fix anything to wallforms use course threaded screws Any waste Durisol can be returned to the factory for recycling, including the mineral wool

insulation.

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