By Shaun, Shelfbank Windows. Published .
Gutters have one job: to collect the rain from the roof and carry it to the downpipes and away from the house. When they overflow, the water pours down the walls instead, and over a winter that can cause damp, staining and damage to the brickwork and foundations.
Most overflowing gutters come down to a handful of causes. This guide explains each one, what you can safely check yourself, and when a repair will not be enough.
Blocked gutters and downpipes
The most common cause is a blockage. Leaves, moss from the roof tiles, silt and the odd tennis ball collect in the gutter and at the outlet, so the water cannot get away. By November, after the leaves have come down, it is the first thing to check.
If water overflows at one corner, check the outlet and the top of the downpipe there. A blocked downpipe often shows itself as water spilling from the outlet or bubbling up at the joint.
Sagging gutters and the wrong fall
Gutters are laid with a slight fall towards the outlets, so the water runs the right way. If the brackets work loose or break, the gutter sags, water sits in the low point, and it spills over in heavy rain.
Sometimes the problem is the fascia board behind the gutter. If it is rotten, the bracket screws lose their grip. Our post on the signs your fascias and soffits need replacing explains what to look for.
Leaking joints
Plastic gutters are joined with clips and rubber seals. Over time the seals perish and the joints drip. You will often see a tell-tale stain on the wall or a patch of green below a joint.
Leaking joints can sometimes be resealed, but on an old run where several are going, a new run of guttering is usually the more lasting fix.
Gutters that are too small
If a gutter overflows in heavy rain even when it is clear and laid properly, it may simply be too small for the area of roof it drains, or there may not be enough outlets. This is common on extensions and conservatories where the guttering was added as an afterthought.
What you can safely check
- Watch the gutters during heavy rain, from the ground, and note where water spills over.
- Look for staining, moss or damp patches on the walls below.
- Check the bottom of each downpipe for water backing up.
- Look along the gutter line for dips or brackets that have come away.
Do not climb ladders to the gutters unless you can do it safely. If they cannot be reached safely, leave it to someone with the right access equipment.
Conservatory gutters
Conservatory gutters collect water from a large, smooth roof, so they fill quickly and are easy to overlook. If water is getting into a conservatory, it is worth checking the gutters and outlets before assuming the roof has failed. Our post on conservatory condensation explains how to tell a leak from condensation.
When to replace the guttering
If the gutters are old, brittle, sagging along their length, or fixed to rotten fascias, replacement is usually better value than repeated repairs. When I replace guttering, the old boards are stripped off, the timber is checked, new uPVC fascias and soffits go on, and the new guttering is run with the correct fall to the downpipes, with the outlets cleared.
Talk to Shaun
If your gutters are overflowing or your roofline needs attention, see our fascia, soffit and guttering page, or our conservatories page for conservatory roofs and gutters. I cover Oswestry, Chirk and the surrounding towns. Call Shaun on 07815 753361 for a free site survey and a fixed written quote.
Related services: Conservatories, Fascia, Soffit & Guttering.