How to replace guttering
If you need to replace your guttering and plan to do the work yourself, you'll find new plastic guttering is the easiest type to fit. Measure all the way round your house to work out the length of gutter you'll need. And check the manufacturer's guidelines to find out how many fittings there'll be.
- When using a ladder, place the bottom quarter of its total height, away from the base of the house. Make sure it is on firm flat ground and not tilting left or right. If using and extension ladder, at least three rungs should be overlapping for stability.
- Have someone holding the ladder and maintain a balanced centre of gravity (belt level) inside the rungs. Wear flat shoes or boots with grip.
- Never lean over or reach out more than an arm's length away. If possible use scaffolding as this is much safer.
There are three different types of guttering: eaves, parapet and valley gutters.
These are the gutters you find at the bottom edge of a sloping roof. They're usually attached to the fascia boards with brackets, and come in a range of shapes and styles in either plastic or metal. Old guttering is often cast-iron, while modern guttering is usually plastic (although aluminium is also sometimes used).
A parapet gutter drains a flat roof between parapet walls (which are walls that continue above the roof level by one or more courses of bricks). One of the parapet walls contains a gap or channel, and the roof slopes slightly towards it. This allows water to drain into a hopper fitted at the top of a downpipe.
The junction between different sloping roofs (such as the one between a gable and hipped-end roof) is called a valley. Metal flashing runs the length of a valley and forms a watertight gutter that channels water into eaves or parapet guttering.
Gutters come in several shapes or profiles, both plain and decorative.
Standard 112mm half-round gutters are used with a 68mm circular downpipe for houses and large detached garages.
If you live in a larger house or in an area of high rainfall, you may need a gutter with a greater capacity - such as 116mm x 60mm 'square' guttering, which has a straight back, front and base.
If you're fitting guttering on a shed, greenhouse or small detached garage, use 75mm half-round gutters and 50mm circular downpipe. This is smaller than the guttering on a house.
These have a straight back edge and fluted front edge, which makes them wider at the top than the bottom. They can be used with square or round downpipes.
Lengths of guttering can have a socket at one end into which the plain (or 'spigot') end of the next piece fits. Or they can be plain at both ends with two lengths joined by a union piece, which contains gaskets to make the connections watertight.
This is the pipe that runs from the guttering to the drain at ground level. Special offset bends are added if it has to fit around overhanging eaves.
A stop-end outlet is an end piece with an outlet that attaches to a downpipe. A running outlet is fixed to a downpipe positioned mid-way along a length of guttering.
Some downpipes have a hopper head that takes a waste pipe or pipes from another source. These can be replaced, if necessary, in existing guttering - but are no longer used in new ones.
Old plastic guttering is relatively easy to remove. But the cast-iron version is extremely heavy and the edges can be sharp - so if this is what you've got, ask someone to help you take it down.
Start by hammering some large nails into the fascia board beneath a section of guttering at both ends. This will hold it in place and stop it from falling down.
Cut through the bolts joining your sections of gutter with a hacksaw. Then tap them out with a nail punch and hammer.
Tie a rope around each end of the section of guttering you want to remove. Break apart the gutter joint and unscrew the brackets that are holding the section to the fascia.
Use the ropes to carefully lower the section of gutter to the ground. Repeat this process to remove all the sections and then take off the downpipes. Use pincers to remove the pipe nails or, if they're rusted in, use a crowbar to lever them out of the wall. Remove the downpipes one section at a time, starting at the top. Finally, you can repair the fascia board by filling in the screw holes, stripping off any flaking finishes and repainting or re-staining it.
Start by fitting the section of guttering with the outlet. This will be joined to the downpipe, which you'll need to position directly over the ground-level drain. It could be a stop-end outlet at the end of the gutter or a running outlet in the middle of the gutter.
Top tip - Heat and cold
Plastic guttering expands in hot weather and contracts in cold. To allow for that, gutter fittings all have a depth mark. When you join sections of gutter or fit a section into a bracket, make sure you carefully line the pieces up to this mark - and don't go past it.
Safety first - Ladder stand-off
It's very dangerous to rest a ladder against guttering. Instead, hook a metal stand-off to the top of your ladder to hold it away from the wall, so its weight isn't resting on the gutter.
Fit a gutter bracket near the top of the fascia board at one end of the guttering (the opposite end to the stop-end outlet, if you have one). Then tie a builder's line or piece of string around the base of the bracket.
To position the gutter outlet accurately, hold a plumb line against the fascia directly over the drain. Mark the position on the fascia with a pencil. Fit the gutter outlet no more than 50mm below the level of the roof tiles - following the manufacturer's advice about the size and number of screws to use.
Stretch your string or builder's line from the bracket along the fascia board and tie it to the outlet. Use a spirit level to check that the string slopes towards the outlet. Although it's not essential, a slight fall (10mm every 6m of gutter) will help the water to drain efficiently.
Mark the position of the other brackets - you should space them no more than 800mm apart, or 600mm if the pitch of the roof is really steep, and no more than 150mm from any joint or fitting. If the outlet is in the middle of the gutter, repeat the process with a bracket at the other end of the guttering run so it also slopes towards the outlet.
Fit the rest of the brackets.
Fit a stop-end to the first length of gutter, and clip the gutter into position on the brackets. The easiest way to do this is to tilt the gutter to fit under the back clip, and then straighten it under the front clip. Line up the gutter end with the insertion depth mark on the bracket.
Fit a union piece at the other end of the first length and screw it into the fascia, then fit the next length of gutter into it. Carry on joining the lengths. Cut the last section to fit using a hacksaw, attach a stop-end and make sure that all the joints line up with the insertion depth marks on the fittings.
This example shows you how to fit your downpipe directly into the outlet. If your eaves overhang, you'll need to bridge the distance between the gutter and your house wall with two downpipe fittings called offset bends - with an off-cut of downpipe fitted between them.
Using a spirit level or plumb line, mark a vertical line on the wall from the outlet to the drain.
Hold a downpipe clip centrally over the line and mark its fixing holes on the wall with a pencil. Repeat this going down the wall, spacing your pipe and socket clips (see Steps 4 and 6) no more than 1.8m apart.
Drill the fixing holes with the size of drill bit recommended by the guttering manufacturer. Put some wall plugs into the holes.
Fit the first length of downpipe with its socket at the top. Make sure you leave a 10mm gap between the end of the outlet and the bottom of the socket to allow for expansion in hot weather. Fix a socket clip over the join and screw it into your wall plugs.
Next, fit the clips to the pipe and screw them into the wall plugs. Carry on fitting the pipe until you reach the bottom of the wall.
Fit the shoe to the bottom of the pipe so it sends water into the drain, and secure the join with a socket clip.