Laying Foundations Cost

In this article, we will go over everything you need to know about the costs involved with this type of work, including the supply costs, labour costs, and any additional costs that may be involved.

How Much Does It Cost to Lay Foundations?

Are you looking for some information on the cost of laying foundations? We will go over this along with the process of laying foundations, the different types of foundations, and the rules and regulations around laying foundations.

So if you're interested in laying foundations prices, read on for everything you need to know.

There are several factors to consider when weighing up the average cost of laying concrete foundations. These factors can include the size and depth needed, the condition of the soil, and the location of the groundwork.

The type of structure you're building will also affect the overall cost. For example, if you are laying foundations for extensions, this is going to cost more than laying decking foundations.

For a typical foundations and groundwork job covering an area of around 24m parameters (enough to accommodate a medium-sized home extension), you can expect to pay around £4500-£6000 for strip foundations and around £5000-£6500 for trench foundations.

These prices include all of the groundwork costs, materials, labour, and waste removal.

Laying Foundations Prices

The table below outlines the average cost to excavate and place foundations at the appropriate depth for a UK home.

The area calculated is based upon an estimated excavation size required for stable foundations. The prices are calculated based on the required infill of concrete for each common foundation type.

Supply Only Costs

In most cases, the quote from your foundations laying contractor will include all of the costs, including the labour and materials costs.

However, if you would prefer to source your own supplies, you may be interested in how much it will cost for the supplies alone.

If you are purchasing supplies yourself, you will need to purchase concrete for the foundations. The price of concrete can vary depending on the quality of the mix. However, the average cost for ready-made concrete is around £150-£250 per cubic metre.

For foundations, you will need a good quality, waterproof concrete mixture to ensure the foundations are safe, can support the building, and adhere to building regulations.

It is not very common for homeowners to purchase the supplies themselves for this type of work. It is recommended that you leave the supplies to the contractor in charge of the work as they will have the skills and knowledge needed to ensure all of the materials are safe and appropriate for use in foundations.

Additional Costs

Suitable foundations are essential when completing any type of building project. With this in mind, there are several additional costs that you may need to budget for with this type of work.

Below is a table showing some of the things that you may need to consider before the foundations laying work can begin:

There are also several other things that you may need to budget for with this type of work. These usually involve additional jobs that you want to have completed along with your foundations work.

Below is a list of the additional things that you may wish to consider when having new foundations laid:

Garden Turf

If your new foundations are accommodating an extension on the back of your home, this may result in some considerable changes to your garden space. If so, you may need to budget for new garden turf along with your foundations work.

The average cost to have new garden turf laid is around £12-£16 per square metre.

New Patio

Similarly, if you are looking to make some changes to your garden, you may want to consider a new patio instead of garden turf. The average cost for an eight square metre patio is around £750-£1000 for a patio made up of concrete slabs. This includes the cost of materials and labour for the work.

Dropped Kerb

If you are having foundations laid for a garage at the front of your home, then you may need to consider having a kerb dropped outside your home.

The average cost for dropping a kerb in the UK is around £700-£1200. However, this will depend on the location of your property and the number of kerbstones that need to be dropped.

New Driveway

Similarly, if you are installing a new garage at the front or side of your property, then you may want to consider installing a new driveway at the same time. The average cost for a typical-sized block paving driveway is around £3000-£4000.

If you would prefer a tarmac driveway, you can expect this to cost around £1600-£3000 for a typical-sized driveway.

Labour Costs and Timescales

The price for the labour and the timescales that you can expect will depend mostly on the size of the foundations that you need.

For an average-sized foundation, you can expect the job to take around 2-4 weeks to complete. This timescale includes preparing the groundworks, inspecting the site, pouring the concrete, and the clean-up and waste removal process.

The timescales can vary due to several factors, including the weather conditions, the ground type, the accessibility of the site, and whether a building control officer needs to inspect the work. Also, if any further work is needed, this will increase the timescales.

Labour for this type of work will usually cost around £1500-£2200 in total. There will usually be a team of tradespeople on site completing the work as it can be quite dangerous to do this type of work alone.

The job is very labour-intensive, so more people working on the job will mean that the work is completed much faster.

There are several things that can affect the overall labour costs for this type of work. These factors can include the ease of the job, the length of time the job takes to complete, the type of company that you hire, and the location of your property.

Those based in the London area can expect to pay more for labour than those in the North or other parts of the UK.

Cost Factors of Laying Foundations

As with all types of construction work, there are several factors that can affect the overall cost of the job. Below is a list of the things that may affect the cost of laying house foundations in the UK:

Type of Foundations

The type of foundation you need will be determined by the type of structure that is being built above it. Strip foundations tend to be cheaper than trench foundations. However, strip foundations usually take longer to construct than trench foundations.

Size of Foundations

The scale of your project will affect the overall timeframes for the work. Plus, larger projects will also require more materials. With this in mind, larger projects will cost more than smaller projects.

The required depth for the foundation will also affect the overall cost. In areas where the soil is prone to shrinkage or where the foundations are located near trees, you may need to install deeper foundations which will take longer to construct and will require more materials.

Type of Ground

The type of ground that you're planning to construct the foundations on will affect the overall cost. Different soil types will require various depths and breadths of foundations.

With this in mind, the timescales to excavate the area and construct the foundations can be affected by the type of ground and will, therefore, affect the overall cost of the job.

Purpose of the Foundations

The purpose of the foundations may also affect the overall cost of the job. If you require house foundations for a double-storey extension, these will need to be able to support greater weight than foundations for a conservatory extension, for example.

This means that the work will require more materials and a greater depth, so the job will take longer to complete. This will result in higher costs.

Location of Property

Your location within the UK will also affect the overall cost of laying foundations. London and the surrounding areas are typically the most expensive when it comes to construction work.

This is due to higher demand and the higher cost of materials. Labour costs, in general, are typically more around the London areas than areas such as the North or other parts of the UK.

Ease of Access

The ease of access to the site can also factor into the job price. Areas that are difficult to reach will end up costing more.

This is because areas that are difficult to access will impact the workflow and may increase the time it takes for the materials to be delivered and implemented.

What's Involved in Foundation Laying?

It is essential to lay foundations properly for any construction work as the foundations will have a knock-on effect for the rest of the building process.

It is important to always check measurements multiple times to prevent any problems from occurring, as mistakes will end up being costly down the line.

Preparation

The first step in laying building foundations is the preparation work. The ground condition needs to be checked over to ensure the right kind of foundations is used.

Before the excavation can start, you must mark out the layout and ensure that it's the correct shape. Start with a single point as a reference for the heights needed, and then calibrate the rest of your measurements to this starting point.

Excavation

Once you have marked everything out and double-checked the measurements, you can then start excavating the area.

The width and depth of the excavation will be determined by your ground type and the foundations plans.

The amount of ground that needs to be removed will be calculated based on the type of foundation and the mass of materials that are needed so that it reaches floor level when in place.

Once the area has been excavated, Building Control will need to visit to sign off on the work or advise on any further work that needs to take place.

You will likely require a skip during this process to remove waste.

Fill The Trench or Strip

Once the excavation work has been signed off, you can then fill the excavated area with concrete.

You should place pegs in the trenches to represent the necessary level needed for the foundation.

Strip foundations require support structures like boards to help with stability.

Once the concrete has been poured, use a rake on the top of the concrete to ensure it is level. Wait for the concrete to completely dry before continuing to the next step.

Bring The Foundations to Ground Level

Next, you need to bring the foundations up to the ground level. The method for this will differ depending on the type of foundation being built.

Take a look at the methods below for the different types of foundations:

Trench-Fill Foundations

Once the concrete has been poured to the desired height, the blockwork can be placed, and a damp-proof course should then be installed.

Strip Foundations

The concrete pour on a strip foundation tends to be much shallower than a trench foundation. This means more blockwork is required below the ground level to raise the foundations to the correct height.

Once at ground level, the wall can then be separated with a damp-proof course before the rest of the construction continues.

Can I Lay Foundations Myself?

Whether or not you can lay your foundations yourself will depend on several factors. This can include the complexity of the build, the scale of the project, and the type of soil that you're building on.

Providing your foundations are quite straightforward, you might be able to complete the work as a DIY project. However, if it is anything more complicated, this should be left to the professionals. This is especially true when working around things such as cables and drains.

A building company will have insurance that covers accidental damage. However, your personal home insurance may not cover any damage that may be caused during the process of the work.

If you do decide to complete this as a DIY job, you will need to have excavation plans before you begin the digging. These plans will usually be supplied by an architect or a structural engineer.

The plans will detail to width and depth of your foundations. You can’t simply start digging and just hope for the best.

If you do complete this as a DIY job, it will still need to be signed off by a Building Control Officer. This applies whether you do the work yourself or let the professionals handle it.

If you don't notify Building Control of your work, you could be handed a pretty large fine, and the work may have to be amended at a later date or complete undone altogether.

In most cases, it is recommended that you choose a professional company to handle your foundations for you.

Building Regulations & Planning Permission For Laying Foundations

Building regulations are a set of structural standards that every new build must adhere to. The work will require an inspection and approval from your local authority.

You can find information about the recommended depth and width of foundations in the Approved Document A, proven by the Building Regulations.

Your structural engineer will usually complete a building survey to determine the type of ground that you have, and this will help them decide which type of foundation would be most suitable for you. They will also submit plans to your local authority for approval.

Once the area has been excavated, your local authority will inspect the area to determine if you can complete the proposed work and to ensure that your site is adequate to support the proposed build.

The cost of this inspection varies. However, you can expect to pay around £300-£450 for this.

Types of Foundations

There are two common types of foundations that are used in domestic settings. These are strip foundations and trench foundations. In this section, we will look at some more information on these two types of foundations and the pros and cons of each type.

Strip Foundations

Strip foundations are usually formed by digging channels into the ground right underneath the location where the walls will be erected. A thin layer of concrete is then poured into the base, and the subsurface walls are built to bring the foundation up to ground level.

Strip foundations usually cost around £3100-£10,500, depending on the size of the area.

PROS

✔ Cheap material costs compared to trench foundations

✔ Great for soil types with good bearing capacity

CONS

✖ Not suitable for every ground type

✖ More time-consuming to construct than trench foundations

Trench Foundations

Trench foundations are created by digging a large surface area and then mass pouring concrete over this large surface area. These foundations use concrete as a footing. This minimises the amount of subsurface blockwork that is needed.

Trench foundations usually cost around £3600-£11,800, depending on the size of the area.

PROS

✔ Faster to construct than strip foundations

✔ Less labour intensive than strip foundations

✔ The load of construction is spread over a larger surface area

CONS

✖ More expensive to build due to the materials

Hiring Contractors to Lay Foundations

You may need to consider several things when finding the right contractor to build foundations for you.

Below is a list of common questions that you should ask when looking for the right contractor for the job:

• Does the contractor have any qualifications that relate directly to constructing foundations?
• What equipment will the contractor be using to complete the job? Will they be using the correct type of equipment? Do you need to provide any equipment?
• Does the contractor possess any form of insurance for the work? You should look for contractors who have insurance covering property damage, personal injuries, and a work guarantee.
• How much experience does the contractor have in building foundations? Can they provide any testimonials or evidence of previous work? Can they provide photos of previous work?
• Does the contractor offer any guarantees with their work? How long does the guarantee last? What issues are covered under guarantee? Will the contractor fix any issues that arise?
• How long will the work take to complete?
• How many contractors will be working on the job?
• Is there anything you need to do to prepare for the job?

FAQs

Sources

https://www.architectsjournal.co.uk/news/opinion/the-regs-take-care-when-building-over-drains-and-sewers