How to Pour a Concrete Foundation

How to Build Concrete Foundations

Thinking about laying a patio, installing a garden shed, or building a base for your greenhouse? It all starts with a strong foundation—and that means concrete. A well-poured concrete base is the backbone of any outdoor structure, offering strength, stability, and long-lasting support.

Whether you're a seasoned DIYer or taking on your first big home improvement project, this guide will walk you through the basics of pouring a concrete foundation—and show you how Speedy Hire can supply all the equipment you need to get the job done right.

Why Pour a Concrete Base?

A concrete foundation provides a level, durable surface that’s ideal for:

• Sheds and outbuildings
• Patios and outdoor seating areas
• Greenhouses
• Hot tubs or garden saunas
• Garden walls or decorative features
• Driveways and hardstanding areas

It’s low-maintenance, weather-resistant, and can even help prevent weed growth underneath your structure.

• Read our guide on Concreting Tips

What You'll Need:

Before you begin, gather your materials and tools. Most of these can be hired from Speedy Hire, saving you money and space:

• Cement mixer – Mix consistent concrete easily
• Wheelbarrow – For transporting mixed concrete
• Shovel – For mixing and levelling
• Tamping beam or straightedge – For smoothing the surface
• Wacker plate or plate compactor - For smoothing and flattening the ground sub-base
• Concrete float or trowel – For finishing touches
• Timber for formwork – To create a frame for the concrete
• PPE – Gloves, boots, and eye protection

Step-by-Step: How to Pour a Concrete Foundation

1. Plan and mark out your area

Measure and mark where your base will go. Use string and stakes to define the edges. Ensure your site is level and clear of debris, including old stones and greenery or twigs.

2. Excavate and prepare the ground

Dig down around 100–150mm (depending on the weight of the structure). Compact the soil using a plate compactor to create a firm base and add a layer of hardcore (crushed stone) for drainage.

• Hire an excavator if your ground is hard to work with, for a faster more efficient result

3. Build the formwork

Using timber boards, build a frame (formwork) around the edge of your base to contain the concrete. Make sure it’s level to the ground and securely fixed in place.

Use brackets, screws and nails to secure the frame together. There should be no gaps around the timber where poured concrete could seep out.

4. Mix and pour the concrete

Using your cement mixer from Speedy Hire, combine cement, sand, and aggregate with water until it’s smooth and workable. Pour into the formwork, spreading evenly.

5. Level and smooth the surface

Use a straightedge or tamping beam to level the surface by dragging it across the top of the formwork. Then use a concrete float or trowel for a smooth finish.

6. Let it cure

Let the concrete cure (harden) for at least 24–48 hours before applying any weight. For full strength, allow 7 days or more. Cover it in warm weather to prevent it from drying too fast and cracking.

Cement Mixer Hire from Speedy Hire

No need to invest in expensive gear you’ll only use once. With Speedy Hire, you can hire everything from cement mixers and wheelbarrows to plate compactors, ground protection mats, and even safety equipment.

Speedy offers:

• Same-day or next-day delivery
• Flexible hire terms
• Nationwide coverage
• Well-maintained, professional-grade tools

Whether you're tackling a garden upgrade or a bigger structural project, they’ve got the kit—and the customer support—to make your project a success.