We fit roof windows into slate, tile and flat roofs across St Austell and the rest of St Austell, PL25. Most of the leaking roof windows we're asked to look at in St Austell were fitted by a general builder or a window company without the correct flashing kit for that roof covering, or with the underlay simply cut and left. Because we're roofers first, a window goes in with the right flashing, the underlay dressed into a drainage gutter above it, and the slates or tiles cut and refixed around it so that it stays dry for as long as the roof does.
Roof windows for the homes of St Austell
The housing in St Austell gives us three common situations. The first is the Victorian and Edwardian terrace with a steep slate roof and a loft full of potential: a pair of roof windows on the rear slope turns that into a usable room or a bright landing. The second is the 1930s semi with a hipped tiled roof, where a roof window over the stairs or into a converted loft is often the only way to get daylight in. The third is the modern estate house in St Austell, PL25 with a flat-roofed extension or garage conversion, where a flat-roof window or lantern changes the whole feel of the room below. We've fitted roof windows in all three across St Austell, and each needs a slightly different approach.
What we do
- New roof windows cut into an existing roof. We trim the rafters, form the opening with proper trimmers, fit the window and the flashing kit matched to your roof covering, and make good the slates or tiles around it.
- Replacing old or failed roof windows. A lot of older roof windows in St Austell were fitted in the 1980s and 90s and are now misted, draughty or leaking. Modern units are better insulated, quieter in rain and fit the same opening.
- Roof windows as part of a re-roof or loft conversion. If we're already re-covering your roof in St Austell, adding windows at the same time is the cheapest it will ever be.
- Flat-roof windows and lanterns for extensions, kitchens and garage conversions, sealed into the EPDM or GRP covering on a proper upstand.
- Sun tunnels for landings, bathrooms and hallways with no outside wall.
- Blinds, electric openers and rain sensors fitted at the same time, so you don't need a second visit.
Slate roofs, conservation areas and planning in St Austell
A large part of St Austell is roofed in natural slate, and some of it sits in conservation areas. Roof windows are permitted development on most houses, but there are limits: the window can't project more than 150 mm from the roof slope, and on a roof facing a highway in a conservation area you may need permission. Recessed or conservation-style windows sit flatter in the roof and are usually what planners in St Austell, PL25 want on a street-facing slope. Listed buildings and flats are different again. We check all of this before you order anything and will tell you plainly if an application is needed.
Why the flashing is the whole job
The window itself is the easy part. What keeps a roof window dry is everything around it. The flashing kit has to match the roof covering, because slate, plain tile and interlocking tile each need a different profile. The breathable underlay has to be cut and dressed into a drainage gutter above the window so any water that gets under the tiles is carried round it. The battens and tiles around the opening have to be refixed so nothing lifts in a Cornwall gale. We photograph the flashing and underlay before the tiles go back so you can see it was done right, and so there's a record if anyone ever questions it.
Choosing the right window
Centre-pivot windows are the standard choice for lofts and are the easiest to clean. Top-hung windows give a clearer view and are better where the window is low and you want to lean out. Conservation windows have a central glazing bar and a black finish for period roofs in St Austell. Triple glazing is worth having on north-facing slopes and bedrooms. We'll talk through the options on the survey and show you sizes against your rafter spacing, because the cheapest way to fit a roof window is to pick a size that sits between the existing rafters.
What happens on the day
For a new roof window in St Austell we arrive with the window, the flashing kit for your roof type and a tower or scaffold already booked. The slates or tiles around the opening come off first and are stacked for re-use. We cut the opening in the roof membrane, trim the rafters with properly sized trimmers so the roof stays as strong as it was, and fix the window frame level and square. The flashing kit goes on from the bottom up, the underlay is dressed into a drainage channel above the window, and the slates or tiles are cut and refixed around it. Inside, we line the reveal, splaying the top and bottom so light spreads into the room, and leave it ready for plastering. On most St Austell houses the outside is weathertight again before lunch and the inside is finished the same day or the next morning. We photograph the flashing before the tiles go back and send the pictures to you.
Cost factors for roof windows in St Austell
The price of a roof window job in St Austell, PL25 depends on four things: the size and specification of the window itself, whether it fits between the rafters or needs one trimmed out, the roof covering (slate takes longer to cut and fix than interlocking tile), and the access. A replacement into an existing opening on a two-storey house with easy ladder access is the cheapest case; a new large window in a steep slate roof with scaffold is the dearest. Adding a second window at the same time costs much less than two separate visits, so if you're thinking of two, do them together.
Our roof window service across St Austell, PL25
We're based in St Austell and work across St Austell, PL25 and the wider area of Cornwall. A single replacement window is usually a day's work. A new opening into an existing roof, with rafters trimmed and the inside plastered, is typically two days plus decorating. We give you a written quote after seeing the roof, we photograph the work, and we come back if anything ever needs a second look.