- Guide price
- £110–£320
- Repair price
- Confirmed once the leak or damage is found
- Condition survey report
- £140–£280
- Coverage
- England, Wales, Scotland, NI
Rhondda Cynon Taf at a glance
- Largest towns
- Rhondda, Tonypandy, Pontypridd, Aberdare
- Postcode areas
- CF
- Building control
- Rhondda Cynon Taf County Borough Council
- Neighbouring areas
- Merthyr Tydfil · Caerphilly · Bridgend · Blaenau Gwent
- Guide price region
- Wales (−8% on West Midlands rates)
How much does a new roof edge or outlet cost in Rhondda Cynon Taf?
Guide prices including VAT at Wales rates. We confirm the price once we've traced the leak or seen the damage.
| Job | Guide price inc VAT |
|---|---|
| Outlet or drainage repair | £110–£320 |
| Localised patch repair | £140–£460 |
| Upstand or flashing repair | £230–£600 |
| Emergency temporary weatherproofing visit | £170–£410 |
| Condition survey and leak investigation | £140–£280 |
Which flat roofs are common in Rhondda Cynon Taf?
Flat roofs in Rhondda Cynon Taf sit on 1930s semis with flat-roofed garages and kitchen extensions, bungalows with flat-roofed side extensions and dormers and low-rise post-war blocks of flats. Wales averages roughly 1,460 mm of rain a year, among the wettest in Britain, so we design for steady run-off: proper falls, clear outlets and upstands well above the finished roof. Approximate 1991–2020 regional averages based on Met Office data.
Building regulations in Wales
Welsh guidance is that most re-roofing needs building control approval, so it's worth checking whenever more than a quarter of a roof is replaced or repaired. Renovated roofs are upgraded to around 0.16 W/m²K where feasible, and new extension roofs are built to 0.13 W/m²K under the Welsh Approved Document L. In Rhondda Cynon Taf the application goes to Rhondda Cynon Taf County Borough Council. More on the rules.
Why does water sit on my flat roof?
Water sits on a flat roof because it can't drain off fast enough: the falls are too shallow, part of the roof slopes the wrong way, the deck has sagged between joists, or an outlet is blocked or set too high.
Current guidance on flat roof design (BS 6229) means most roofs need to achieve a finished fall of at least 1:80, and roofs are commonly designed with a steeper fall, such as 1:60, so that building tolerances and deck deflection still leave enough slope. Many older roofs were built with less, or have settled over time.
A small amount of water that clears within a day or two of rain is often tolerable. Deeper ponding that lingers adds weight, holds dirt and debris, can shorten the life of some coverings and turns any small defect into a leak. A patch won't fix it, because the problem is the shape of the roof. The fix is to correct the falls, either with firring pieces under a new deck or with tapered insulation in a warm roof, or to add or lower outlets so water has somewhere to go. Our ponding water guide explains this in more detail.
Do flat roofs need overflows?
Roofs that drain to internal outlets or behind parapets should normally have an overflow, so that if an outlet blocks, water spills somewhere visible instead of rising over the upstands and into the building.
An overflow is usually a spout or weir set through the parapet or kerb at a level below the top of the upstands. When water runs from it, that is a sign the main outlet is blocked or overloaded. On a simple roof that drains over a drip trim into an external gutter, the open edge itself does the same job.
We look at where the water goes in heavy rain, how many outlets the roof has for its size, and whether the outlets, hoppers and downpipes are clear and properly connected. Leaf guards on outlets help on roofs near trees, as long as they are cleared regularly.
Which towns in Rhondda Cynon Taf do we cover?
Edge trims, outlets and drainage in Rhondda Cynon Taf: questions
Which towns in Rhondda Cynon Taf do you cover?
All of Rhondda Cynon Taf. The main towns have their own pages below, and if yours isn't listed we still cover it: send your postcode and we'll confirm.
How much does a new roof edge or outlet cost in Rhondda Cynon Taf?
£110–£320 for an outlet or drainage repair, at Wales guide rates including VAT. We confirm the price once we've traced the leak or seen the damage.
Which council handles building control for a flat roof in Rhondda Cynon Taf?
It depends on where the roof is: in Rhondda Cynon Taf that's Rhondda Cynon Taf County Borough Council. Welsh guidance is that most re-roofing needs building control approval, so it's worth checking whenever more than a quarter of a roof is replaced or repaired. We confirm which applies at the survey.
What's the difference between a drip trim and an edge trim?
An edge trim finishes the edge of the roof and holds the waterproofing down. A drip trim has a profile that throws water clear into the gutter. On many roofs a single trim does both jobs.
Can you add a new outlet to an existing flat roof?
Usually, yes. The outlet is cut in at a low point, connected to a downpipe or gutter, and the waterproofing is dressed into it with compatible materials. Whether it solves ponding depends on whether water can actually reach it.
Can a flat roof be re-laid with better falls?
Yes, as part of a replacement. Falls are corrected with tapered firring pieces under a new deck or with tapered insulation in a warm roof build-up.
Everything about edge trims, outlets and drainage → · All flat roofing in Rhondda Cynon Taf →