Planning a home extension is an exciting project, but getting the concrete work right is essential for a strong and durable result. From foundations and footings to floors and other structural work, concrete plays an important role throughout an extension project.
For many homeowners, ready mix concrete offers a convenient way to get the required concrete delivered directly to the building site without the time and labour involved in traditional on-site mixing.
But how do you know how much concrete you need? Which type is suitable? And what should you prepare before the delivery arrives?
This guide explains what homeowners should consider when ordering ready mix concrete for a home extension.
Why Is Concrete Important for a Home Extension?
A home extension adds additional space to an existing property, which means the new structure needs a properly prepared base. Concrete may be required for foundations, footings, floor slabs and other elements depending on the design and construction method.
The concrete specification should always match the requirements of the project. Factors such as structural loads, ground conditions, depth and the design provided by your builder or structural engineer can influence the appropriate solution.
Using the correct concrete from the beginning can help create a solid foundation for the rest of the construction work.
What Is Ready Mix Concrete?
Ready mix concrete is professionally prepared concrete that is delivered to the project location ready for use. Rather than mixing cement, aggregates and water manually on-site, homeowners can arrange for prepared concrete to arrive when it is needed.
This can be particularly useful during an extension project because construction sites often have limited space for storing materials and mixing concrete.
Ready mix concrete can also reduce the preparation work required from the construction team, allowing them to concentrate on placing, levelling and finishing the concrete.
How Much Concrete Does a Home Extension Need?
The amount of concrete required depends on the dimensions and design of the extension.
For a simple rectangular section, you can estimate the volume by multiplying:
Length × Width × Depth = Concrete Volume
For example, if a section is 6 metres long, 4 metres wide and requires a 0.1 metre depth of concrete:
6 × 4 × 0.1 = 2.4 m³
This gives an estimated volume of 2.4 cubic metres.
However, extension projects are not always simple rectangles. Different foundation depths, irregular shapes, slopes and multiple sections can affect the final calculation.
It is therefore sensible to discuss your measurements and project requirements with your concrete supplier before placing an order.
Ready Mix Concrete for Extension Foundations
Foundations are one of the most important parts of an extension.
They transfer the load of the new structure into the ground, so the foundation design should be determined according to the property’s requirements and professional specifications.
When ordering concrete for foundations, do not choose a mix simply because it appears suitable for another type of project. Your builder, engineer or project specification should determine the required concrete grade and performance characteristics.
Once the specification is known, a ready mix supplier can help arrange the appropriate quantity and delivery.
Concrete for Extension Floor Slabs
A floor slab provides the base for the finished floor within many types of extensions.
Before the concrete arrives, the site needs to be properly prepared according to the construction design. Depending on the project, this may involve ground preparation, insulation, reinforcement and other layers.
The required slab thickness and concrete specification should be confirmed before ordering.
For homeowners, accurate measurements are particularly important because a shortage of concrete during a pour can create delays and additional logistical problems.
What Are the Benefits of Ready Mix Concrete for Extensions?
One of the biggest advantages of ready mix concrete is convenience.
Less On-Site Mixing
Traditional concrete mixing requires cement, aggregates, water, equipment and labour. Ready mix concrete arrives prepared for the intended application, reducing the amount of mixing required at the property.
Faster Preparation
A planned delivery can help the construction team move directly into the pouring stage rather than spending significant time preparing multiple batches.
Consistent Supply
Professionally prepared concrete can provide a more consistent mix than repeatedly mixing separate batches manually on a building site.
Better for Limited Spaces
Home extension projects can take place in relatively small gardens, driveways or restricted areas. Having concrete delivered can reduce the need to store large quantities of raw materials on-site.
Convenient Delivery
The concrete can be delivered directly to the project location, making it easier to coordinate the material supply with the construction schedule.
What Should You Check Before Ordering Concrete?
Before contacting a ready mix supplier, collect some basic information about your project.
You should know:
- The type of work being completed
- The approximate length and width of the area
- Required depth or thickness
- Estimated concrete volume
- Project location
- Preferred delivery date
- Site access conditions
- Whether concrete pumping may be required
- Any specific concrete grade requested by your builder or engineer
Having these details ready can make it easier to discuss your requirements and receive an appropriate quotation.
Can a Concrete Pump Help With a Home Extension?
Yes. Concrete pumping can be useful when the delivery vehicle cannot get close enough to the exact pouring location.
For example, an extension may be located behind a house with a narrow passage, restricted driveway or other obstacle between the road and the construction area.
A concrete pump can help move concrete from the delivery point to the required location, making placement easier in difficult-access areas.
The type of pump required depends on the site layout and the distance and height the concrete needs to travel.
When Should You Arrange Concrete Delivery?
Timing matters because concrete needs to be placed and finished once it arrives.
Before arranging delivery, make sure the construction area is ready and the team is available to receive and work with the concrete.
Your site preparation should include confirming:
- The pouring area is ready.
- Formwork is correctly positioned where required.
- Reinforcement has been installed according to the project design.
- Access for the delivery vehicle has been considered.
- Workers and necessary equipment are available.
- The concrete quantity and specification have been confirmed.
Good preparation helps avoid unnecessary waiting and allows the concrete work to proceed efficiently.
What If Your Extension Site Has Restricted Access?
Restricted access is common for home improvement projects, particularly where an extension is being built at the rear of a property.
Before booking your concrete, consider the route from the road to the pouring area.
Look for:
- Narrow entrances
- Low overhead clearance
- Gates or walls
- Tight turns
- Sloping driveways
- Limited parking space
- Nearby buildings or obstacles
Tell your concrete supplier about any access limitations before delivery.
If the mixer cannot reach the pouring area directly, pumping may provide a practical alternative.
Ready Mix Concrete vs Mixing Concrete Yourself
For a very small project, some homeowners may consider mixing concrete themselves. However, an extension can involve considerably more concrete than a small garden project.
Manual mixing can require substantial amounts of cement and aggregate, along with additional labour and time. Maintaining consistency between individual batches can also become challenging.
Ready mix concrete removes much of this preparation by providing concrete through a planned delivery.
For larger pours, this can make the process more efficient and easier to coordinate.
How to Avoid Ordering Too Much or Too Little Concrete
Incorrect quantity calculations can cause unnecessary problems.
Ordering too little may mean that the team has to arrange additional concrete while the work is already underway. Ordering significantly more than required can result in material waste.
Start with accurate measurements and calculate each section separately if the extension has different areas or depths.
For example, if the project includes separate foundation trenches and a floor slab, calculate each area rather than treating the entire extension as one simple measurement.
It is also worth discussing the final quantity with your builder or concrete supplier before confirming the order.
Choosing a Ready Mix Concrete Supplier in London
If you are searching for ready mix concrete in London, consider more than the price.
A suitable supplier should be able to discuss your project requirements and provide information about delivery, concrete options and access considerations.
Metro Ready Mix supplies ready mixed concrete for residential and commercial construction projects across London. The company also provides volumetric concrete and concrete pump hire, giving customers additional options when project conditions require a different delivery or placement solution.
Metro Ready Mix supports projects ranging from home improvements and extensions to foundations, driveways, slabs and larger construction work.
Ready Mix Concrete for Homeowners in West London
Homeowners across West London may need concrete for extensions, foundations, driveways, patios and other property improvements.
Metro Ready Mix provides concrete delivery solutions across London and lists areas including Uxbridge, Brentford, Barnes, Alperton, Acton, Twickenham, North London and West London.
For a home extension, providing the supplier with your project location, measurements and delivery requirements can help ensure the order is planned appropriately.
Frequently Asked Questions
What type of concrete is used for a home extension?
The appropriate concrete depends on the structural design and application. Foundations, footings and floor slabs can have different requirements, so homeowners should follow the specifications provided by their builder, engineer or architect.
Is ready mix concrete suitable for home extensions?
Yes. Ready mix concrete can be used for various parts of a home extension, including foundations and slabs, provided the supplied mix meets the project’s requirements.
How do I calculate concrete for an extension?
For a simple rectangular section, multiply the length, width and depth to calculate the volume. More complicated extension designs may require separate calculations for different sections.
Do I need a concrete pump for an extension?
Not always. A pump may be useful when the concrete delivery vehicle cannot access the pouring area directly. Site layout and access conditions determine whether pumping is appropriate.
How should I prepare my property for concrete delivery?
Make sure the pouring area is prepared and that the delivery route has been considered. Clear any obstacles that could prevent safe access and tell the supplier about restricted or difficult access before delivery.
Can Metro Ready Mix deliver concrete for residential projects?
Yes. Metro Ready Mix provides ready mix concrete for domestic projects as well as commercial and construction work. Its services include ready mixed concrete supply, volumetric concrete and concrete pump hire.
Final Thoughts
Concrete is a fundamental part of many home extension projects, and getting the specification, quantity and delivery arrangements right can help keep construction moving smoothly.
Ready mix concrete provides a convenient alternative to extensive on-site mixing, particularly when a project requires a larger quantity or when space and labour are limited.
Before ordering, confirm your concrete requirements with your builder or engineer, measure the project carefully, check site access and make sure the construction area is ready for delivery.
For homeowners planning an extension in London, Metro Ready Mix can provide ready mix concrete, volumetric concrete and pumping solutions tailored to different project requirements. Contact the team to discuss your project and arrange a concrete quote.