Once the ground floor slab has been poured and moved, you have completed your home’s infrastructure and are ready to begin the superstructure. This means everything above ground.
Depending on the size of your house, the next two weeks will be completely covered with masonry and brickwork which, depending on whether your house is a one-story or multi-storey house, is moved to the level of the ground floor ceiling.
The main things to monitor with your block seams, unless you are building them yourself, are Damp Proof Coursing (DPC), wall ties and wall insulation. For the purpose of this article we will focus on a 300mm bore wall which is one of the most popular ways to build a house.
In order to prevent high humidity from appearing on the walls, it is critical that a layer of DPC be placed at ground floor level under each wall. For example, if you are building a 215 mm (9 in) block on a flat wall, a 215 mm wide layer of DPC should be placed first and then built on top of it. Appropriate DPC should also be incorporated around windows and doors, i.e. below and behind window sills, door and window battens and also across window and door headers (tops). Any good home building guide will display drawings detailing the positions and sizes of the appropriate DPC in specific areas.
Correct DPCs are one of the most important details to get right when building your home and will prevent a lot of potential problems if implemented correctly.
For external walls, using the example of a 300 mm bore wall, which consists of two blocks 100 mm wide at the edge separated by 100 mm, another detail to watch for is the wall insulation and wall strapping.
Wall ties are used to hold the two separate panels together and make the block more stable. Generally, the ties are placed on top of the first course of blocks spaced at centers 900mm and then spaced 450mm vertically as the blocks work height. The purpose of the drip built into the middle of the tie is to prevent water from clogging the cavity from the outside in. There is usually a plastic clip on the tie which is used to hold the wall insulator in place masonry Braintree.
The wall insulation, which is generally between 50mm and 75mm thick (ask for advice from your engineer) should be placed in the cavity tightly against the inner sheet to make the block and the main thing to check is that there is no gap between the block and the insulation as this can It has a great influence on the effectiveness of insulation. Other places where insulation is necessary during the block construction phase are at the back of the window sill to prevent a cold bridge from forming from the outside to the inside.
The heads of windows and doors should be spread over a sill of appropriate size. Generally, openings less than 2.5m wide can be spanned by a concrete sill bearing 200mm on both sides of the opening. If the opening is wider than that, you should consult your engineer for a suitable type of lintel, eg. RSJ steel lintel or steel lintel.