Installation Advice for Water Butts and Rainwater Diverters

A practical guide for homeowners and contractors on fitting water butts and rainwater diverters correctly.

Why Use Water Butts

Collecting rainwater with a water butt is a straightforward way to reduce mains water usage in your garden. A successful water butt installation depends on choosing compatible parts and fitting the diverter correctly. This guide covers everything from compatibility checks and step-by-step fitting to troubleshooting common issues, helping you get the most from your setup.

Compatibility Checklist for Water Butt Installation

Gutter and Downpipe Type

Check whether your downpipe is round or square, and measure its diameter. Most diverters are designed for standard UK sizes (e.g. 68 mm round or 65 mm square). Choose a diverter that matches your downpipe profile to avoid unnecessary adapters.

Available Space

Measure the area where you plan to position the water butt. The butt should sit on a firm, level surface close to a downpipe. Allow space for the diverter connection and easy access to the tap.

Water Butt Capacity and Tap Position

Select a capacity that suits your garden size and rainfall. Ensure the butt has a threaded outlet at a convenient height for attaching a hose or watering can. Check that the diverter kit includes a suitable hose connector.

How to Fit a Water Butt Diverter: Step-by-Step

Mark the downpipe – Hold the diverter against the downpipe at the desired height (usually 300–500 mm above the top of the water butt) and mark the top and bottom of the diverter body.
Cut the downpipe – Use a fine-tooth saw or pipe cutter to make two horizontal cuts at your marks. Remove the section of downpipe between the cuts.
Fit the diverter – Slide the diverter into the gap, ensuring the sealing gaskets sit snugly against the pipe. Secure with the screws provided (hand-tight only to avoid cracking the plastic).
Connect the hose – Attach the flexible hose from the diverter outlet to the water butt inlet. Use a hose clip or jubilee clip to secure the connection.
Position the water butt – Place the butt on a stable, level stand or base. Ensure the inlet aligns with the hose and the tap is accessible.
Test the flow – Fill the downpipe with water from a bucket or wait for rain. Check for leaks at the diverter joints and hose connection. Adjust if necessary.

For more detailed product-specific instructions, refer to the manual supplied with your diverter kit. Our Water Butt Range includes compatible diverters and accessories to simplify fitting.

Essential Accessories for a Successful Installation

Filters and Debris Screens

A rainwater filter or debris screen prevents leaves, moss, and grit from entering your water butt. Fitting a filter at the diverter inlet keeps the water cleaner and reduces blockages in the hose and tap.

Connectors, Stands, and Overflow Kits

Use a flexible hose connector to bridge the diverter and butt. A sturdy stand raises the butt for easier tap access and improves water pressure. An overflow kit diverts excess water away from the foundation, preventing unwanted pooling near your property.

Troubleshooting Common Water Butt Installation Issues

Leaks at diverter joints – Ensure the sealing gaskets are correctly seated and the screws are tight but not over-tightened. Check that the downpipe cut is clean and straight.
Poor water flow – A blocked filter or debris screen is the most common cause. Clean the filter regularly, especially after heavy rain or storms.
Overflow problems – If the butt overflows before the diverter cuts off, verify that the diverter’s float valve or shut-off mechanism is working. Also check that the overflow hose is not blocked or kinked.
Blocked tap or hose – Flush the system occasionally by opening the tap fully. If sediment builds up, fit an inline filter at the butt inlet.

If you encounter persistent issues or need advice for a larger installation, contact us for guidance tailored to your project.

Choosing The Right Setup For Your Needs

For most homeowners, a standard water butt kit with a round downpipe diverter and basic filter provides a reliable solution. Contractors working on new builds or large gardens may prefer a filtered diverter system with a higher-capacity butt (200 litres or more) and a robust stand. If you are retrofitting an existing downpipe, look for a diverter with adjustable clamps or adapters to fit non-standard pipe sizes. Our Water Butt Installation Products page lets you filter by downpipe type and capacity to find the right match quickly.

Shop Water Butts

Frequently Asked Questions

Can I install a water butt myself or do I need a professional?

A basic water butt installation is a straightforward DIY job for most homeowners with basic tools (saw, screwdriver, tape measure). For complex setups involving multiple downpipes or underground pipework, a professional may be advisable.

How do I prepare my water butt for winter?

Before frost arrives, drain the water butt, disconnect the hose, and store the diverter and any removable parts indoors. Leave the tap open so any residual water can expand without cracking the butt.

How often should I clean the filter on my rainwater diverter?

Check the filter every two to three months, or more frequently if you have overhanging trees. A quick rinse with a hose removes most debris.

What size water butt do I need for my garden?

A 200-litre butt is suitable for an average UK garden. Choose two smaller butts linked together if space under a single downpipe is limited.

Can I fit a diverter to a square downpipe?

Yes, square downpipe diverters are available in standard 65 mm and 75 mm sizes. Ensure you select the correct size for your pipe profile.

More FAQ's

Ready to Start Your Water Butt Installation?

Browse our full range of water butts, diverters, filters, and accessories to build the perfect setup for your home or project.

Shop Water Butts