Estimating the costs for foundations and piling can be a challenge, with various factors affecting the final cost. Our cost calculator is designed to take into account as many of these variables as possible to give an indicative cost.
If you’d like a fully accurate quotation for your piling works, please get in touch with us directly.
Calculating the cost of foundations
While it is impossible to create a completely accurate costing prior to starting work, as conditions on site may not be fully apparent until breaking ground, our calculator is designed to factor in as many of the key variables as possible and give you an indication of the potential foundation and piling cost per metre for your project.
We include items such as the size and height of the building, to identify the best type of foundations, and accessibility issues that will have an immediate impact.
We’re happy to speak to you to provide a more personalised estimate, so please don’t hesitate to get in touch to find out more about how to calculate the cost of your pilings or foundations.
What factors affect the cost of groundworks and foundations?
Various factors affect the cost of foundations per square foot, including size and accessibility.
The first influence is the type of foundation your building requires – strip foundations with a trench of concrete are the cheapest, while piling is generally the most expensive. The type of building will determine which type of foundation is required.
The next thing that affects the cost is another obvious one – the larger the footprint of the building, the more area there will be to install foundations and therefore the cost of materials and labour will be higher.
A basement foundation cost per square foot will generally be lower than the cost of a foundation for a home or business development, simply because of the size, but both will still be affected by other factors that aren’t related to the size of the building.
The accessibility of the building site affects how easy it is to get equipment and materials in place and whether or not specialist equipment is required. If the site is on uneven ground, levelling or additional excavation may be required, as well as disposal of excavated soil – unless you opt to redistribute the soil for landscaping purposes, which will reduce the cost.
The quality of the subsoil will also have an effect on the cost of laying foundations. Clay soils can expand or contract based on moisture content and may need additional work to ensure the safety of the foundations. Any contamination of the site will also involve additional costs during the groundworks phase.
Things to consider when planning your groundworks
When planning a build, whether for a dwelling or commercial building, there are various things you should consider. Using the right contractors is the main consideration – no building is safe without the right foundations, and to prevent delays and issues with building regulations and inspectors, you need to get things started out properly.
There are no shortcuts when it comes to the stability of your building, so working with a groundworks specialist will ensure that you are covering all your bases and taking into account all of the site conditions and requirements.
The design of a property will affect the required foundations, so getting your contractors to communicate with one another from an early stage will help prevent delays. If you’re having a strip footing foundation, for example, and have a large concrete volume, planning in advance so that the concrete supplier can rotate trucks and get loads prepared at the right time can avoid having to wait for each truck to refill and return.
What is a piling foundation?
Piling is a form of deep foundation, used for large and heavy buildings, including blocks of flats and offices. They can be as deep as 20-65 metres. Depending on the ground conditions, these foundations might be end-bearing or friction piles.
End-bearing piles rely on having a layer of very solid soil or rock, deep in the ground. Piles will be driven into this layer and the load of the building transfers through the piles onto this stable layer. If there isn’t a layer of solid rock, or it is too deep, friction piles are used instead. These transfer the load through the soil, using friction.
What other types of foundations are there?
Different types of foundations are designed for different building types. Shallow foundations are used for smaller buildings, including houses. They can be installed at a depth of as little as 1 metre, and include individual footings, strip footings, and raft or mat foundations.
Individual footings distribute loads horizontally and used when the load of the building is carried by columns, with concrete mix in reinforcement cages being used to fill foundation holes on the site. These are most suitable for lightweight structures.
Strip footings use trenches filled with concrete then built up to ground level using blockwork. Building loads are carried across walls rather than columns. Raft or mat foundations are designed for conditions where the soil is too weak to support footings, and the building loads need to be spread over a larger area. The weight of the building is spread over the entire footprint of the building, using a slab of concrete.