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Repairs and surveys

Edge trims, outlets and drainage across Lancashire

Edge and drainage work in Lancashire covers garages, extensions, dormers, flats and commercial roofs. We fit GRP or aluminium trims, raised kerbs at walls, new or repaired outlets, gutter runs and overflows, all fixed to a sound deck edge and finished with materials compatible with the roof. Rotten fascias and deck edges are replaced first.

Aluminium drip trim discharging into a new black gutter beside a roof outlet on a rubber flat roofComputer-generated example image
Guide price
£110–£330
Repair price
Confirmed once the leak or damage is found
Condition survey report
£140–£290
Coverage
England, Wales, Scotland, NI

Lancashire at a glance

Largest towns
Preston, Burnley, Blackburn, Blackpool
Postcode areas
BB, FY, L, LA, OL, PR, WN
Building control
Preston City Council, Burnley Borough Council, Blackburn with Darwen Borough Council and 10 other councils
Neighbouring areas
Greater Manchester · Merseyside · Cheshire · West Yorkshire
Guide price region
North West (−5% on West Midlands rates)

How much does a new roof edge or outlet cost in Lancashire?

Guide prices including VAT at North West rates. We confirm the price once we've traced the leak or seen the damage.

JobGuide price inc VAT
Outlet or drainage repair£110–£330
Localised patch repair£140–£480
Upstand or flashing repair£240–£620
Emergency temporary weatherproofing visit£170–£430
Condition survey and leak investigation£140–£290

Which flat roofs are common in Lancashire?

Flat roofs in Lancashire sit on 1960s and 1970s link-detached houses with flat-roofed garages and porches, shops with flat-roofed rear stores below flats and 1930s semis with flat-roofed garages and kitchen extensions. The North West is one of England's wetter regions, averaging roughly 1,290 mm of rain a year, so falls, outlets and well-detailed upstands matter more than the membrane colour. Approximate 1991–2020 regional averages based on Met Office data.

Building regulations in England

Replacing more than half of a roof over a heated room usually counts as renovating a thermal element, so it is insulated to current standards and notified to building control. Renovated roofs over heated rooms are insulated to around 0.16 W/m²K where that's feasible, and new extension roofs are built to 0.15 W/m²K. In Lancashire the application goes to Preston City Council, Burnley Borough Council, Blackburn with Darwen Borough Council and 10 other councils. More on the rules.

Should I fix the edges and drainage or replace the whole roof?

Fix the edges and drainage on their own if the covering is in good condition and the deck is sound. If the covering is near the end of its life or the falls need correcting across the whole roof, it is usually better value to do everything together as part of a replacement.

Trims and outlets are bonded into the waterproofing, so replacing them means cutting into the covering around the edge. On a roof with plenty of life left, that is a worthwhile repair. On an old, brittle covering, the new detail can end up stronger than the roof around it, and correcting falls means taking the covering off anyway. Our repair or replace guide sets out how to decide.

How long do flat roof trims and outlets last?

Properly fixed GRP or aluminium trims and well-installed outlets should last about as long as the waterproofing they are part of. What shortens their life is poor fixing, movement in a rotten deck edge and blockages that are never cleared.

A quick check of outlets and gutters each autumn, and again after storms, prevents most drainage problems. Look for leaves and silt in outlets, gutters pulling away from the fascia, trims that have lifted or split at joints and staining on the wall below the edge. The maintenance guide lists what to check and when. Only check what you can see safely from the ground, a window or a ladder at the edge, and never walk on a roof that isn't designed for it.

Which towns in Lancashire do we cover?

Edge trims, outlets and drainage in Lancashire: questions

Which towns in Lancashire do you cover?

All of Lancashire. 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 Lancashire?

£110–£330 for an outlet or drainage repair, at North West 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 Lancashire?

It depends on where the roof is: in Lancashire that's Preston City Council, Burnley Borough Council, Blackburn with Darwen Borough Council and 10 other councils. Replacing more than half of a roof over a heated room usually counts as renovating a thermal element, so it is insulated to current standards and notified to building control. 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.

Do new trims need building regulations approval?

Not usually on their own. Approval only becomes a question if the work is part of a larger re-roofing job or alters the structure.

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