Replace a damaged gutter section safely from a ladder, matching parts, cutting to size, and sealing joints so rainwater drains properly.
GTR-01Identify and buy matching partsCheck the profile of your existing gutter — half round, square line, or deepflow — and its size, usually 112mm or 114mm across. Take a short offcut or a clear photo to a builders' merchant, since different brands rarely fit together. Buy enough new gutter to cover the damaged run plus 150mm spare, a union/jointer, and replacement brackets if any are cracked.
GTR-02Gather tools and set up the ladderYou'll need a hacksaw, spirit level, cordless drill/driver, bucket and gloves. Set the ladder on firm, level ground and have someone foot it if you're working above head height — move the ladder rather than overreaching. Don't attempt this job in high wind or heavy rain.
GTR-03Clear the gutter and catch debrisScoop leaves and silt from the gutter run either side of the damaged section using a gloved hand or small trowel. Old gutters often hold standing water, so put a bucket or old sheet underneath before you disturb anything — it will pour out once released.
GTR-04Remove the damaged sectionUndo the union or jointer clips with a flathead screwdriver and unclip the gutter from its support brackets. Slide the damaged length free. If old sealant has it stuck, ease it gently rather than forcing it, which can wrench the bracket screws loose from the fascia.
GTR-05Check and clean the fascia boardPress the exposed fascia board with a screwdriver point. If it gives easily, the timber is rotten and needs repair before you refit anything — that's a separate job. Wipe old sealant and grime off the fascia and any brackets you're keeping, so the new joint sits flush.
GTR-06Measure and cut the new lengthMeasure the gap between the two remaining gutter ends, including how far the pipe needs to sit inside each union. Mark the new section with a pencil and square, then cut it with a hacksaw, keeping the blade square so the joint doesn't sit crooked. File the cut edge smooth to remove burrs and sharp plastic.
GTR-07Fit any new bracketsHold a replacement bracket against the fascia at the same fall line as its neighbours and mark the screw holes. Drill a small pilot hole and fix with a 25mm galvanised or stainless screw — fascia boards are solid timber, so no wall plug is needed. Space brackets no more than 1m apart, closer to joints.
GTR-08Set the fall towards the downpipeGuttering needs a slight slope so water runs to the downpipe — roughly a 1mm drop for every 600mm of length is the usual guide. Use a spirit level with a thin wedge under one end, or a string line, to check and adjust the bracket before fixing the new section in place.
GTR-09Fit the new section and seal the jointsClip the new gutter length into its brackets, then push each end fully into the union/jointer so it seats against the rubber seal — most modern unions simply click into place. On older screw-fit unions, run a thin bead of gutter sealant along the joint for extra security.
GTR-10Test with waterAsk someone to run a hose into the gutter at the highest point while you watch the repaired joints from below. Check for drips at the unions and confirm water flows steadily to the downpipe outlet without pooling anywhere along the run.
GTR-11Tidy upTake the ladder down and store it safely. Most councils accept rigid plastic guttering at the local recycling centre rather than in the kerbside plastics bin, so set the old offcuts aside for a tip run. Wipe down your tools and put them away.
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