Façade defects · Water ingress
Roof and parapet leaks: causes, risks and repair.
Why roofs, parapets and their junctions leak, how an intrusive survey from inside and out finds the cause, and the repair options zone by zone.
| At a glance | |
|---|---|
| What it is | Water getting through roof coverings, upstands, parapets, valleys or outlets. |
| Main risk | Damage to the rooms below, wet insulation and structural timber, and disruption to occupied buildings. |
| Common on | Hotels, offices and apartment blocks, especially where plant and walkways sit on the roof. |
| Usually spotted by | Staff and residents on the top floor, after heavy rain. |
Where roofs leak
Most roof leaks start at the details, not the open field of the roof: upstands, parapets, abutments, valleys, outlets, rooflights and plant supports. On pitched roofs, slipped or broken slates and failed leadwork are common causes; on flat roofs, splits and failed laps in the membrane.
How to recognise it
- Ceiling stains and drips on the top floor.
- Ponding water and blocked outlets.
- Split, blistered or lifted membranes.
- Slipped or broken slates and tiles.
- Cracked copings and open joints on parapets.
Why it happens
- Age of the covering and its details.
- Poor detailing at upstands, abutments and outlets.
- Damage from foot traffic and plant installations.
- Exposure to wind and weather on open sites.
Why it matters
- Damage to finishes, insulation and structure below.
- Disruption in occupied buildings such as hotels.
- Spend. Patch repairs without the cause fixed repeat the cost.
How we investigate it
- Zone the roof from aerial imagery, so every finding is located consistently.
- Inside: examine the structure, insulation and underlay from the roof space, opening linings locally.
- Outside: inspect slopes, ridges, valleys, upstands and leadwork close-up from powered access, lifting slates where needed.
- Report zone by zone, with a repair strategy for each. Simple fixes are made on the spot.
How it is put right
- Local repairs to slates, leadwork, membranes and upstands.
- Clearing and renewing outlets and gutters.
- Coping and parapet repairs.
- Overlay or replacement where the covering is at the end of its life.
From our investigations
Examples from our own work. Client and building details are withheld.
See our published case studies
What to send us
The address, where the leaks appear, roof access arrangements, photos and any previous roof reports. Email enquiries@mtconsult.co.uk, use our contact form or call 0800 048 5229. We typically respond within one working day.
Frequently asked questions
Can you survey while the building is open?
Yes. Surveys of hotels and other occupied buildings are planned around their operations.
Do you make repairs during the survey?
Where a simple fix can be made safely on the spot, our team makes it there and then.
Can you look at other areas in the same visit?
Yes. With access already on site, we can extend the survey to nearby roofs, canopies and windows.
Related
Talk to us
A roof that keeps leaking?
Our in-house contracting team provides the access and opening-up, so you have one point of contact.