The short answer
A sound roofing guarantee should cover defects in the workmanship for a stated number of years, state clearly what it excludes, and be written down with the job address, the work done and the date. Materials are usually covered by the manufacturer separately. It should say how to make a claim, who to contact and whether it passes to a new owner. A promise made only in conversation is hard to rely on.
Workmanship, materials and the difference
Two things can fail on a roof: the way it was built, and the products it was built from. A workmanship guarantee comes from the contractor and covers faults in how they did the job, such as a flashing that was not dressed properly, a tile that was not fixed, or a membrane that was poorly sealed at a lap. A materials guarantee usually comes from the manufacturer and covers a defect in the product itself, for example a tile that crumbles early. Good paperwork identifies which is which, and who to contact for each. If a roofer says everything is guaranteed, ask them to put in writing exactly what that means.
The essentials of a written guarantee
A useful guarantee names the contractor and gives their address and phone number. It names the property, describes the work, and states the date of completion. It sets out the term in years and the point at which the term starts. It describes what is covered, in plain words, and what is excluded. It says what the contractor will do if a covered fault appears, normally to repair it at no charge, and within what time. It explains how to make a claim, including whether you must notify them in writing and allow an inspection. Anything less is a sales line.
Be clear on what a guarantee is not. It is not the same as buildings insurance, which pays for sudden damage from events like storms. Our page on what an insurance-backed roofing guarantee is explains the version where a third party stands behind the promise, and what to check in it.
Exclusions you should expect to see
Every guarantee has limits, and reasonable ones are fair. Typically they exclude damage caused by storms, fallen trees and accidents, which are matters for insurance. They exclude wear and tear and normal ageing, moss growth and lack of maintenance, and damage caused by other people working on the roof afterwards, such as an aerial fitter or a solar installer. They may exclude pre-existing faults that the contractor did not work on. Read these carefully and ask about any that seem broad. A long list of exclusions that swallows the cover is a weak guarantee, however many years it claims.
Maintenance conditions deserve a thought. Some guarantees ask you to keep gutters clear or to have the roof inspected at intervals. Those are reasonable if they are stated up front, but check that you can meet them. Cleaning can also matter: our page on whether roof cleaning voids a tile warranty shows how a wrong method can cause trouble.
Term, transfer and who stands behind it
A long term sounds good, but ask who will honour it. A promise from a one-person business is worth what that business is worth in ten years, and an insurance policy or a manufacturer's scheme can add a layer. Ask whether the guarantee transfers to a buyer if you sell; the page on passing a roof guarantee to a buyer explains why that matters at sale. Keep the guarantee with the quote, invoice and any Building Regulations paperwork in one place.
If you are comparing roofers, put their guarantees side by side with the quotes, as set out in how many quotes to get for roof work. And if a guarantee has not been honoured, what to do if you are unhappy with a roofer's work explains the next steps.
Evidence you will need later
A guarantee claim is easier when you can show the roof as it was left. Ask the roofer for photographs of the finished work, and of any hidden parts that were covered up, such as the underlay, the battens, the lead in its chase and the flashings before the tiles went over them. Keep your own photographs dated and filed. If the work needed Building Regulations approval, keep the completion certificate or notice. When a fault appears years later, a clear record shows that the work was done as described and helps separate a workmanship failing from ordinary wear. It also helps a future buyer's solicitor, who will ask for the paperwork.
Finally, read the notice requirements. Many guarantees ask you to report a fault within a set time of finding it, and to stop anyone else working on the area first. If you ignore that, a valid claim can be refused on a technicality. Diary a yearly look at the roof from the ground, and report anything odd at once.
Our own guarantee
At Beacon we give a written workmanship guarantee of 10 years on our work, and we describe it in full on the guarantee page before you agree anything. We survey the roof first and photograph its condition, so the starting point is on record. You can return to the homepage to see the work we cover, or ring 01256 213956 with questions.
Every roof is different. A free survey with photos settles it for yours.
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