Summary: Learn how to repair a gutter, unblock a gutter, re-align a gutter, repair a UPVC gutter, prevent a UPVC gutter from leaking, repair a metal gutter and prevent a metal gutter from leaking.
When carrying out repairs to guttering, always use a ladder with stand-off brackets or have the base of the ladder supported by a helper. Also remember that although a metal gutter will hold the weight of a ladder, a UPVC gutter will not.
Unblocking a gutter
All kinds of objects and debris, from leaves and tennis balls to birds’ nests and dead birds, can block guttering causing it to overflow.
- Cover the drain to prevent debris falling down the downpipe and blocking it.
- From the top of the ladder use a trowel to clear out debris from the gutter but do not overstretch – move the ladder.
- Flush water down the gutter with a hose. If the water does not disperse, re-align the gutter. If the water overflows at the downpipe, this indicates it is blocked (see Downpipe repairs).
Re-aligning a gutter
If water does not drain away down a gutter, this is usually due to loose guttering. Tighten or replace loose screws holding the gutter in position. If there are several sections of loose guttering then the fall may be affected and the guttering will need to be re-aligned.
- Drive long nails into the fascia board at regular intervals to support the section of guttering being re-aligned. If the section of guttering is longer than 2m (6ft 6in) or is made of iron, more nails will be needed to support it.
- Remove the supporting brackets.
- Run a string line the length of the fascia board just below the guttering. Check that it falls towards the position of the downpipe. The fall should be 15mm-20mm (6/10in-8/10in) for every 3m (9ft 10in).
- Re-position the brackets moving them slightly to the left or right to allow you to screw them into solid wood.
UPVC gutters
Leaks from UPVC guttering are generally located at the union joints where two sections of guttering are connected. A union joint will have rubber gaskets to produce a watertight joint. Leaks are caused when the gasket is worn or by dirt forcing the seal apart.
- Squeeze the sides of the guttering to remove it from the union piece.
- Clean away any dirt from around the gasket.
- If there is no dirt, check the gasket for wear.
- To replace a worn gasket, with the guttering still disconnected from the union piece peel the worn gasket away. Fit the new gaskets, pressing them firmly into place.
- Refit the guttering into the union piece by squeezing the guttering and releasing it into the union piece.
Metal gutters
Rust should be treated as soon as possible.
- When removing rust always wear safety goggles to protect your eyes from rust particles.
- Rust can be removed from small areas using emery cloth, while larger areas of rust can be removed with a wire brush or wire brush wheel attachment fitted to an electric drill.
- Once all the rust has been removed apply rust-neutralizing primer to the affected area.
- At the same time check for any small cracks and fill them with roof-and-gutter sealant. Larger cracks and even holes can be repaired with the same glass-fibre filler used for repairing damage to the bodywork of cars. Smooth the filler thoroughly to ensure silt or water will not be trapped by any roughness.
- Apply black bitumen paint or gloss paint. When the first coat has dried apply a second coat.
Leaking metal gutters
Corrosion can make removing the nuts and bolts on a metal gutter difficult. Therefore it’s best to try and repair the leak without dismantling the gutter.
- Scrape the joint with a screwdriver or paint scraper to clean away all dirt and debris. Wear thick gloves to protect the hands from rough metal edges.
- Using a hot-air gun dry the cleaned joint thoroughly, then using a sealant dispenser apply roof-and-gutter sealant to the joint.
- If this does not resolve the problem, unscrew the nut holding the bolt to the joint section. If this is impossible because of corrosion you will have to saw off the head of the bolt with a hacksaw. Then use a hammer and nail punch to knock the shank of the bolt loose.
- Tap the joint section with a hammer to detach it from the guttering.
- Use an old wood chisel to scrape away the putty and a wire brush to remove the rust from the joint area. Wear safety goggles for this part of the job.
- Apply metal primer to the ends of the gutter and the joint section and let it dry thoroughly.
- Apply roof-and-gutter sealant to the joint section and position the guttering back in place. Secure the joint section to the guttering with a new nut and bolt.
Tools needed
- Ladder with stand-off brackets
- Trowel
- Hosepipe
- Wire brush
- Electric drill
- Screwdriver
- Paint scraper
- Hot-air gun
- Applicator gun
- Hacksaw
- Hammer
- Nail punch
- Wood chisel
Materials needed
- Emery cloth
- Wire brush wheel
- Rust-neutralizing primer
- Roof-and-gutter sealant
- Glass-fibre filler
- Bitumen paint
- Gloss paint
- Metal primer
Related projects
- Joining pipes
- Removing an air lock in a water pipe
- Tap repairs
- Burst pipe
- Self cutting taps
- How to cut pipe
- Covering a flat roof
- Fitting a roof window
- Flashing repairs
- Downpipe repairs