Originally Posted On: https://www.pm247.co.uk/blog/how-to-install-garden-soakaway/

How to Install a Soakaway: A Guide to Garden Drainage

If you’ve ever stood in your garden after a heavy downpour and wondered why your lawn turns into a mini lake, you’re not alone. Here at PM247, we’ve helped countless homeowners across the UK tackle persistent and stubborn surface water issues. One of the simplest, most cost-effective solutions fix this issue is the humble soakaway. It’s the unsung hero in domestic drainage – and in this article our drainage engineers have put together a guide to tell you what it is, how it works, and how to install one yourself (and when it’s best to call in the pros!). So, starting at the beginning..

What Is a Soakaway?

A soakaway, in essence, is a very large hole or pit dug into the ground and filled with a material like rubble or, more commonly these days, a purpose-made plastic crate system. Its job is simple: collect excess rainwater and allow it to drain slowly and naturally back into the soil – returning it to the water table fast and efficiently. Think of it like a giant covered garden plug hole.

You’ll usually find a soakaway positioned in your garden or lawn, at the end of a drainage or down pipe that collects rainwater from roofs and guttering, by driveways, or near other hard surfaces.

Naturally, the water might have just ebbed away or flowed into a ditch or nearby river, but with modern building and our tendency to concrete huge areas, sometimes nature needs a helping hand. A soakaway can reinstate some of the natural water movement – without the mess, flooding, or long-term damage.

Why Might You Need a Soakaway?

Here in the UK, where rainfall can be frequent and unpredictable, particularly in the winter, standing water in your garden is more than just a nuisance. Left unchecked, it can lead to:

• Waterlogged lawns and flowerbeds
• Damage to your home’s foundations or walls
• Problems with damp or mould
• Driveways and paths becoming slippery or cracked
• Breeding grounds for insects

Installing a soakaway helps to manage this water properly, reducing the risk of flooding or water pooling, and will keep your property well-drained for years to come.

Thinking about Installing a soakaway? Call PM247 on 08082 504 203, or book a visit online and let the professionals take care of it for you.

The Many Benefits of Installing a Soakaway

There are several reasons why more and more homeowners are opting for a soakaway:

• Eco-Friendly: A soakaway uses natural filtration and avoids putting extra strain on the mains drainage system – which is commonly already under strain.
• Cost Effective: Once installed, it needs little maintenance and can last for decades.
• No Planning Permission Required: In most cases, especially for rainwater from roofs and patios, no permission is needed.
• Protects Your Home and Garden: Stops water from pooling near your property, helping prevent long-term structural damage.
• Supports Sustainable Urban Drainage: A simple way to support sustainable water management in built-up areas.

Can You Install a Soakaway Pit Yourself?

The short answer is – Yes! With the right tools, materials, and a bit of elbow grease of course. But it’s not always straightforward. Below we’ll outline the process for you, but do bear in mind that soil conditions, existing drainage systems, and building regulations can all play a part. If you’re unsure, give our team at PM247 a call – we’re happy to advise or carry out the installation for you.

What You’ll Need

Before you get started, you’ll need to gather a few key tools and materials:

Materials:

• Soakaway crates (modular plastic crates are popular and easy to install)
• Soakaway membrane (prevents soil from clogging your soakaway)
• PVC underground drainage pipe
• Sand or fine gravel (for bedding and levelling)
• Shingle or gravel (optional, depending on the design)

Tools:

• Spade or digger (depending on the size of the hole)
• Spirit level
• Tape measure
• Hacksaw (for cutting drainage pipe)
• Drill or hole saw (to connect pipe to crates, if needed)

Step-by-Step: How to Install a Soakaway

1. Check Suitability

Before you start digging..! It would be wise to perform a percolation test to check the soil drains well. Dig a small hole, about 300mm wide x 300mm deep, fill it with water and time how long it takes to drain away. If it’s still there 24 hours later – you may need a different drainage solution.

Note: Remember to make sure your soakaway is at least 5 metres away from your home and at least 2.5 metres from your boundary (to avoid affecting neighbours or structures).

2. Plan the Route

Plan where your soakaway will go, usually in the lowest point of the garden. Lay out where your drainage pipe will run from the downpipe or rainwater gully to the soakaway.

3. Dig the Trench and Soakaway Pit

For domestic use, soakaways are typically around 1 cubic metre (1m x 1m x 1m). Use a spade or mini-digger to excavate the area. Make sure the trench for the drainage pipe slopes very slightly (a 1:40 fall is ideal) to allow gravity to do the work.

Note: If your drainage issue is larger, you may need a larger soakaway.

4. Line the Pit with a Membrane

Use a non-woven soakaway membrane to line the entire hole and trench (basically a permeable layer of cloth). This stops soil from entering the crate and clogging the system while still allowing water to pass through.

5. Install Soakaway Crates

Place the crates into the hole. Most crates slot together and are designed to be stackable. Connect the drainage pipe to the crate (you may need to cut an inlet using a hole saw).

6. Wrap and Backfill

Wrap the membrane over the top of the crate so it’s completely enclosed. Then backfill with the excavated soil, tamping it down gently as you go.

Note: For improved drainage, some people add a layer of gravel or shingle above the crates before topping with soil or turf.

7. Reconnect and Test

Reconnect your downpipe or gully to the new system. Pour water down the drain to ensure it flows correctly into the soakaway and that there are no leaks or blockages.

Cost of a Domestic Soakaway

So, how much does it actually cost to install a soakaway in your garden? Well, like most home improvements, it depends on a few things – the size of the soakaway for one, the type of crates used (some can be expensive), access to your garden, and whether you’re doing it yourself or hiring a professional.

DIY Soakaway Costs

If you are a keen diy’er and fancy getting stuck in and doing the job yourself, here’s a rough breakdown of what you’ll need to budget for (costs are estimated at time of writing):

• Soakaway crates: £75–£200 (for a 1m³ system)
• Geotextile membrane: £30–£60
• Underground drainage pipe: £20–£50 (depending on length needed)
• Extras (gravel, sand, fittings): £25–£50
• Tool hire (mini digger for a weekend): £80–£150 (optional, but highly recommended if digging a full metre down)

Estimated total: £180–£460, depending on how much you can do by hand and what tools you already own.

Time investment:
For a confident DIYer, allow at least a full weekend – and potentially more if you’re digging by hand. The digging alone can be backbreaking, especially in clay-heavy soils. And if you’ve never done this kind of drainage work before, expect a few extra hours figuring things out as you go.

Professional Soakaway Installation Costs

Bringing in a drainage professional like PM247 will, of course, cost more – but you’ll save time, avoid mistakes, and ensure the job’s done to regulation standards.

Prices typically start at around £850 to £1,500 for a standard domestic soakaway, depending on:

• Site access and ease of excavation
• Soil type (clay or stony ground may require more work)
• Distance from the property or drain connection
• Any additional pipework or landscaping required

Some larger or more complex installs (or those tied into bigger drainage issues) may cost a little more, but most domestic jobs fall comfortably within this range.

Time required:
Most soakaways can be installed by a professional team in 1-2 days, depending on the weather and ground conditions.

Is a Soakaway Pit Worth the Spend?

If your garden is prone to regular waterlogging or your current drainage setup isn’t cutting it, a soakaway is a very sensible investment. Not only does it protect your garden and property, but it can also add to your home’s overall health and value.

When Should You Call in the Professionals?

Installing a soakaway isn’t rocket science, but it can be a headache. If any of the following applies, it’s worth getting in touch with a professional drainage team like PM247:

• Your garden has heavy clay soil (slow-draining)
• You’re dealing with persistent or large-scale flooding
• You’re not sure how your existing drainage system works
• The installation is near a building or structure
• You’d rather not spend your weekend digging a 1m-deep hole!

We’ve got all the equipment and know-how to get the job done quickly, safely and in line with current regulations. Plus, we can assess your garden, run soil tests, and design a drainage system that actually works – not just for now, but for years to come. Here’s what our customers think of our work:

Final Thoughts on Garden Soakaways

Rainwater management might not be the most exciting part of being a homeowner – but it’s one of the most important. A well-installed soakaway is a brilliant, budget-friendly way to protect your garden, prevent damage to your property, and do your bit for sustainable drainage.

Whether you’re the DIY sort or would prefer to let the experts handle it, PM247 is here to help. From simple advice to full soakaway installation and drainage surveys, we’re on call 247 to keep your home dry and your garden looking its best.

Need Help with Drainage or Soakaway Installation?

Get in touch with PM247 today – we offer fast, friendly, and professional service across the UK. Call us on 08082 504 203, or book a visit online and let’s get that water flowing in the right direction.