Despite not being visible when a house extension is complete, laying appropriate foundations is an important element of any building project. It’s not only essential that you choose the right foundation system for the soil type present, but also that measurements are made very carefully and accurately to plan. Errors in this area of a building project could have serious ramifications, and in worst case scenarios, could involve a completed project being demolished, wasting considerable time and money. Ground conditions vary, from project to project, and problems are often only apparent when you break ground.
Hometech’s dedicated team of building specialists can take care of preparing your site and laying the correct foundations for your building project. Costs can vary depending on the types of foundation used and it’s sensible to have an appropriate contingency budget available for your project.
Types of foundations
Simple/strip foundations - it’s standard to place as little solid concrete as possible into trenches and then to add blocks up to ground level, where the walls switch to brick or stone or whatever the chosen external cladding is. Just above ground level, the footings are topped with a damp-proof course and then the ground floor becomes fixed
Engineered foundations - if, however, the ground is considered difficult, you could dig the foundation trenches deeper and then fill with a greater depth of concrete, sometimes fitting sheets of polystyrene beside the trenches to act as a slip membrane. If the site requires deep foundations then using concrete rafts is a solution
Piled foundations - piles are driven into the ground and then filled with concrete and the foundation gets topped with a ground beam
Raft foundations - a concrete raft ‘floats’ on the ground beneath. The structure is made up of an extra-thick floor slab, strengthened by masses on steel reinforcing. Rafts have the advantage of providing the base of a ground floor solution, not just wall trenching, but they are reckoned to be rather more complex to construct.