📋 Roofing guide
One of the most common questions we are asked. The honest answer depends on the specific condition of your roof — here is how an experienced roofer thinks about it.
Most homeowners dread being told their roof needs replacing. It is the most expensive outcome, and it is also the one that some less scrupulous roofers are quickest to recommend — because a replacement is a much larger job than a repair.
After more than 30 years working on roofs across Merseyside, our view is straightforward: if a repair will solve the problem properly for the next ten to fifteen years, you should have the repair. A replacement is only the right answer when the roof as a whole has deteriorated to the point where piecemeal repairs would not hold.
Here is how we actually think through this on a survey.
A well-laid concrete interlocking tile roof should last 40 to 50 years. Natural slate can last considerably longer. A roof that is 20 years old and in generally sound condition, with a localised problem, almost always warrants repair. A roof that is 45 years old and showing widespread deterioration — cracked and slipped tiles across multiple sections, failing mortar throughout, perished underfelt visible — has reached the point where ongoing repairs would cost more over five years than a replacement, and give you less peace of mind.
Age alone is never the deciding factor, but it sets the context for everything else.
The underfelt — the breathable membrane that sits beneath the tiles — is the roof’s secondary line of defence. If it has perished and torn, it is no longer preventing water reaching the roof timbers and insulation when driven rain finds its way under the tiles. You cannot repair or patch underfelt effectively; the only remedy is to strip the roof and re-lay it from scratch.
We check the condition of the underfelt on every survey. If it is failing, that is usually the clearest indicator that a replacement is the right answer, whatever the condition of the tiles above it.
If the underfelt is sound, a repair to the tiles or flashings above it is almost always viable.
A roof with three cracked tiles, a failed flashing above a dormer and a loose ridge tile is a roof with three problems that can each be fixed. A roof where you cannot replace a cracked tile without disturbing four more, where the ridge mortar is failing throughout and where the verge mortar is crumbling across its full length — that is a roof where the work required to make it sound is approaching the cost and disruption of a replacement, at which point a full strip and re-lay often makes more sense.
The test we apply: could a repair be expected to give ten to fifteen years of trouble-free performance? If yes, repair. If the underlying condition means that is unlikely, replacement.
Prolonged water ingress through a failing roof can damage the underlying timber structure — rafters, battens, purlins. If timbers have rotted, they need to be replaced when the roof is stripped. This adds to the cost of a replacement, but it is also a reason why a leaking roof should not be left: the longer it leaks, the more timber is at risk, and a replacement that might have cost £8,000 if done promptly can cost significantly more if the structure is compromised.
We assess the visible and accessible timbers as part of every survey. If there is evidence of rot, we identify the extent before quoting.
We will never recommend a full replacement when a repair will do the job properly. That statement is on our website, in our quotes and it has been the way we work for over 30 years. A repair is a smaller job and therefore less income for us — but a customer who gets honest advice is a customer who recommends us to their neighbours, and that has been the basis of our business since we started.
If you call us and the survey shows the roof needs a repair, we will quote for the repair. If it genuinely needs replacing, we will explain clearly why and give you a detailed written quote for the replacement. You will always know exactly what we think and why.
We carry out free surveys across Formby, Southport, Crosby, Liverpool, Ormskirk, Hightown and Maghull. Call or WhatsApp us and we will arrange a convenient time.
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