What can be mended without a new roof
A conservatory roof is a frame holding sheets or panes, and faults tend to show at the joints between them, not in the middle of a sheet. That makes many of them repairable.
- Glazing bar seals and end caps that have perished, which let water run down the bar and drip inside.
- A single cracked or clouded sheet or pane, replaced to the same size and thickness.
- Sheets that have slipped in their bars, reseated and refixed.
- Flashing or sealant along the house wall, where the roof meets the brickwork.
- Ridge and eaves trims that have worked loose.
- A gutter that has sagged or blocked, so water sits against the roof edge.
Each of these is a repair of a part, with the roof structure left alone. Where water is the complaint, the guides on a leaking conservatory roof and on wall flashing leaks work through the causes in turn.
A repair holds only if the part beneath it is sound. If the glazing bar is corroded or rotten, a new seal on it will not last, and the repair is a stop-gap rather than a fix. That is judged on the survey, not guessed from the ground.
Seals, bars and sheets in general terms
The three parts fail at different speeds. Seals are soft, sit in the sun and the weather, and are the first to go. The bars carry the weight of the sheets and the load of wind and snow, so they last longer but can bow, corrode or lift at the fixings. The sheets are the covering, and they discolour, craze or split with age.
A repair works on one of these parts:
- New seals and caps along the bars, which stops drips if the bar underneath is sound.
- New sheet or glass in an opening, which needs the old size taken off the roof, not guessed.
- Bar replacement, which is bigger because the sheets either side have to come off.
Be wary of a quick coat of sealant over everything. Sealant covers a failing joint without fixing it, and a roof that moves with the temperature will open it again. A proper repair removes the failed part and fits a new one, so the joint is made again and not just covered.
Photographs of the bars from inside, in daylight, tell a lot before anyone climbs up. Look for dark streaks, white salts or staining along each bar, since they show where water has been running.
When replacement is the better buy
Repair stops making sense when you are paying for it every year. Four signs point to replacement:
- the problems are spread along most bars, not one or two
- the frame at the wall plate or ridge is soft or rotten
- the sheets are crazed, yellowed or brittle across the whole roof
- the roof is also too hot, cold or noisy, which a repair will not change
Photographs of the whole run of bars show how far the trouble spreads. Age matters here too. For polycarbonate, HomeBuilding's typical figure is 10 years and The Eco Experts say about 10 to 15 (page updated 29 April 2024). Treat them as ranges, since a sound roof can outlast them. The guide on polycarbonate roof lifespan looks at how the ageing shows.
As a yardstick, a full replacement is quoted by MyJobQuote at between £3,200 and £6,000 (page dated 20/10/26), and by The Eco Experts at between £2,300 and £6,000 (29 April 2024). A repair that eats a fair slice of that, on a roof with little life left, is hard to justify.
Getting a straight answer on the repair
The roof is inspected before any figure is given, and photos show you what is wrong. That is how you tell a repair from a pitch for a new roof.
Ask whoever surveys for these things:
- which part has failed, shown in a photo, and not described in general
- what the repair will cost compared with the replacement, so you can weigh them
- how long they expect the repair to hold, given the age of the rest of the roof
- what else the visit found, such as a failing gutter or flashing
A fair answer sometimes says that the roof can be mended and should be left otherwise. That is worth hearing, because a repair can be the right result. Where the answer is replacement, the options and their consent routes are on the conservatory roofs page.
If the leak is bad, cover the contents, catch the water and take photos of the damage. If it is a storm loss, tell your insurer first, make the room safe and keep receipts.
