The short answer
Yes. Building work next door can loosen tiles and slates through vibration, knock ridges and chimney stacks, tear flashings where a new wall joins your roof and drop debris into gutters. Photograph your roof before the work begins, check it again afterwards, and report anything you find promptly and in writing, with dated pictures. A roofer's report on the cause and the repair strengthens your case.
How building next door can harm your roof
A roof is a lightweight, loosely connected structure compared with the walls that carry it, and it responds to what happens around it. Demolition, piling, excavation and heavy plant can all send vibration through the ground and the party wall. Slates and tiles sit on battens by small fixings, and an old roof with tired nails does not need much shaking to let a few slip.
Other damage is more direct. Where a new extension or a raised wall joins your house, the lead flashing that seals the junction may be cut, pulled or buried. That flashing, usually lead and occasionally another metal, closes the gap where the slope meets the masonry, so once it is disturbed, water follows. Scaffolding tied to or leaning against your roof can crack slates, and loads of materials or workers stepping across your slope do the same. Debris, dust and mortar end up in gutters and valleys and clog them, and a clogged gutter overflows into the eaves.
Removal of a shared chimney stack or a change to a shared roof line can also leave your side exposed. These are the sort of effects that are easy to miss until the first wet weather.
Record the roof before the work starts
The best evidence is a record made before anyone arrives. If you know a neighbour's project is coming, whether from a conversation or a planning notice, take a set of photographs while the roof is still untouched.
Cover every slope, the ridge, the chimney, the valleys, the gutters and any flat roof. A zoom lens or binocular view from the ground is enough for the outside, and a torch in the loft shows the inside: the underside of the covering, the timbers, and the ceilings below. Date each picture, or save them with the date visible in the file information, and store them somewhere safe.
If your roof is already worn, say so in your own notes. A fair record does not pretend a tired roof was perfect, it shows what was there. That honesty helps, because a contractor's insurer will otherwise argue that any defect predates the work.
Our page on how to inspect a roof from the ground describes the safe way to do this, and a set of roof photographs before work is worth having whatever the reason. Our roof inspections service can carry out the closer survey.
What to check once the work is under way or finished
Look again at the roof during the work if you can do so safely, and always when it finishes. Go through the same list each time.
- Slipped or cracked slates and tiles. Compare with your earlier pictures, course by course.
- Ridge and hip tiles. Check for movement, gaps or fresh mortar cracks.
- The party wall junction. Look at any lead where the new work meets your roof, and check it is sealed and not buried in debris.
- Chimneys. Look for new cracks in the pointing, leaning pots and displaced flaunching, which is the mortar bed that grips the pots.
- Gutters and downpipes. Check for debris, dents and sagging.
- The loft. Look for daylight, new damp patches and wet insulation.
- Ceilings and walls inside. A fresh stain after rain is a sign water is entering.
New cracks in plaster or brickwork near the shared wall may also point to vibration. They are worth recording alongside the roof.
If a ceiling stain appears, mark its edge and date it. Rain on a roof that was disturbed is when a hidden fault shows itself.
Who to tell and how
Tell your neighbour and, if you know them, the builder or the site manager, as soon as you find something. Do it in writing, by email or letter, and attach your photographs. A friendly note that describes what you saw, where, and when you last saw the roof undamaged is more effective than a phone call, because it is a dated record.
Keep a copy and note any reply. If the neighbour's work falls under the Party Wall etc. Act 1996, such as work to a shared wall or some excavation close to your foundations, they should have served notice first, and the Act requires them to compensate you for loss or damage that the work causes. A party wall surveyor or solicitor can advise on your rights. We are not able to give legal advice, so for the legal position please ask a professional.
It is sensible to tell your own home insurer too, especially if there is any active leak. Insurers usually want photographs, a description of the cause, and a quote for repair. Standard policies tend to exclude gradual wear and tear, so a clear record of when and how the damage appeared matters. Do not assume a claim will succeed, but good evidence gives it the best chance.
Getting a roofer's report on the cause
When there is a dispute, the useful question goes beyond whether the roof is damaged to what damaged it. A roofer who can get to the roof safely can tell fresh breakage from old weathering. A clean break on a slate, with no moss in the crack, suggests a recent knock. A rusted nail head tells a different story, pointing to age rather than the builders next door.
A report should say what is wrong, where, the probable cause, and what repair is needed, with photographs of each item. It helps to separate defects that appear related to the works from those that were already there. That keeps the claim fair and makes it harder to dismiss.
For a roof that is not safe to access, a pole camera or a drone can capture images without anyone climbing. Our page on a roof inspection checklist shows what a proper survey covers, and how often a roof should be looked at in any case is explained on the page about how often to inspect a roof.
Making the roof good and keeping the evidence
Where damage is real, the repair should go back to what was there. On older houses that means matching the covering, keeping slate as slate and stone as stone, and putting the lead back properly. Where a neighbour or their insurer will pay, they will want a clear scope and a fixed price, and we provide both in writing after a survey. An active leak gets made watertight before anything else, and we prioritise it.
Keep all the paperwork together: your before and after photographs, the roofer's report, letters, and invoices. If the matter is slow to settle, you may need to make the roof watertight yourself and recover the cost later, so keep every receipt.
For the lease side of a similar dispute, see our page on a roof dilapidations survey. Our area is Bath plus 30 road miles around it. Call 01225 285181, WhatsApp us or use the form. Have your dated photographs to hand when you call, as they help us compare the roof now with how it looked before the work started.
