Question A

A trench fill foundation would be appropriate in this location because when the ground conditions consist of firm clay that is lying on chalk at approximately 1 meter below ground level the ground is sufficient enough to take the bearing capacity. The reason why trench fill foundation is suited for this build is because it is good for transferring long continuous loads such as walls and spreads the weight of the building over the whole foundation, and the firmness off the clay will easily be able to support it. The dimensions of this foundation have to be 1m deep and no more than 150mm wider than both sides of the wall, and the length can be to the end of the wall. The depth is important because “ at such depths seasonal changes,which result in changes to soil moisture content, are unlikely” (S.Emmitt 2006, p.71). The foundation itself is very economic for small builds because its one of the foundations that uses the least amount of concrete and therefore will make the build a lot cheeper overall.

Question B

I have chosen a pile foundation for this location because the ground is identified as having a high volume-change potential and using pile foundations “it takes the load of the building through made up ground or weak soil to load bearing strata. The ground beams transfer the building loads to the piles.” (S Emmitt 2010, p.42). The other reason i chose this type

was because the piles themselves can be wrapped in a polythene sleeve which allows the ground to move willingly and to reduce frictional uplift, so that none of the structure fights the heave process which then forms cracks and tension on the construction. The void in the diagram below the floor also allows the ground to heave and swell freely.

Question C

The foundation i have chose i would ensure dampness from the outside couldn't effect the inside by having a suspended concrete floor will meet the requirements if it incorporates a ventilated air space. This should measure at least 150mm clear from the ground to the underside of the floor. (Building Regs 2000, p.27 4.19b)I have also chosen to have a cavity wall with DPC put in the brick work and block work at 150mm above outside ground level to stop damp rising in the external brickwork. The flooring will be a polythene damp proof membrane laid on top of my suspended concrete floor and under neath my 65mm screed layer and then tucked under my DPC from the block work and made sure its stuck and sealed at all edges to stop any damp from getting in. I would also put air bricks in the walls to allow the flow of ventilation to stop moisture from condensation but make sure they are at opposites to allow the air to flow through the building and at slightly different heights to overcome different levels.

Bibliography

Stephen Emmit & Christopher Gorse, 2010. Barry’s introduction to construction of buildings. 2nd ed. Oxford:Wiley-Blackwell Stephen Emmit & Christopher Gorse, 2006. Barry's advanced construction of buildings. 2nd ed. Oxford:Wiley-BlackwellBuilding regulations 2000, Site preparation and resistance to contaminates and moisture. Approved document C, p27 4.19