Flat roofing in Spetisbury

What is up there now. Felt, nearly always. Either a three layer built up system finished with a mineral cap sheet, or a single torch on layer laid straight over the covering before it.

It fails with splits along the creases where the sheet has been folded, blisters where damp was sealed in underneath, and a lifted or failed seam where the covering turns up an upstand. The last one is the worst, because water then travels under the whole roof.

What we put back. EPDM rubber on a plain rectangle, bonded down in one sheet so there is no lap or seam anywhere in the open part of the roof. GRP fibreglass where a roof has kerbs, corners and upstands to laminate round, or where somebody will walk on it. Single ply, hot air welded, on a longer run.

The deck and the fall. Under the covering is plywood, OSB or chipboard decking on joists, with firrings on top making the fall towards the outlet. Chipboard that has been wet swells, gives underfoot and has to come off, and it is the single biggest swing in the price. A roof laid dead flat holds standing water, and ponding in the same corner every winter will finish a new covering as surely as it finished the old one. BS 6229 sets out the falls, and where re-firring will not work we form them in tapered insulation.

Heated rooms need the insulation moving. Renewing a covering over a kitchen or a bedroom brings the insulation into scope under Part L. On a flat roof the right place for it is above the deck, on a vapour control layer, in PIR, with the membrane over the top. That is a warm roof, and everything structural stays dry. The old cold roof, insulated between the joists, puts the boards below the dew point, so interstitial condensation forms inside the build up and rots them from above while the covering still looks sound. Building control are notified and inspect it open.

Edges, junctions and openings. These take the time, and they are the parts a cheap quote leaves out. A chase raked into the wall at the abutment, lead dressed into it as a cover flashing, a cavity tray above it. A coping on the parapet with an apron below. A kerb under every rooflight, lantern, Velux style flat roof window, hatch and soil or vent pipe, so the covering turns up an upstand. A drip trim on the free edges. And a rainwater outlet running to a hopper, a downpipe or the gutter. A garage is a day, an extension two or three working days, and we say how long first.

A Spetisbury flat roof has no rate per square metre. Laying the membrane is the quick part. What sits under it decides the price.

The deck. Spetisbury garages and extensions from the sixties and seventies were often decked in chipboard, and chipboard that has taken water for years sags between the joists and crumbles at the edges. Sound boards stay. Soft boards come out. Thomas lifts an edge or looks from inside before he quotes, because nobody can tell from the ground.

A heated room underneath, or not. Over a garage the roof can go straight back. Over a kitchen or a bedroom it needs insulation board to meet Approved Document L, which raises the roof, and that can mean lifting the upstands and trims and working round a window head or a door.

The fall. Many Spetisbury roofs of this age were laid nearly dead flat and hold puddles for days. Firrings to build a proper fall add timber and time, and they stop the new covering ponding in the same spot as the old one.

Getting to it. A garage off a drive takes a tower. An extension at the back of a terrace needs every board and roll carried through, and the work at height rules still decide the platform.

Ask anyone else quoting which membrane they are laying, EPDM, GRP or torch-on felt, whether the deck is being replaced or covered over, and whether the falls and insulation are in their price.

Plenty of Dorset villages come with a conservation area over the housing and a long list of controls on what a roof can be. Spetisbury does not. For most addresses in the village there is nothing to apply for and nobody to satisfy on appearance, which means the covering on your garage or your extension is genuinely your decision.

In Spetisbury that freedom is worth spending in the right place, and it is almost never on the covering itself. A premium membrane laid over a soft deck and a fall that goes nowhere will fail on the same timetable as a cheap one. So if there is money to put anywhere, put it into replacing tired decking, into firrings that give the roof a real fall, and into a properly sized outlet with somewhere for the water to go. Then pick the covering that suits the shape of the roof. We quote it that way round, with the deck and the falls as their own lines, so you can see exactly what you are buying and what you are choosing to leave.

We cover Spetisbury, Charlton Marshall, Sturminster Marshall and north to Blandford Forum. Boscombe, where our base is, lies 14.2 miles away, and building control for all of these villages sits with Dorset Council.

You would be dealing with Bournemouth Roofing & Building Ltd, incorporated under company number 15471719 and registered in England and Wales. The business belongs to Thomas Hannen, and he is the one who gets up on the flat roof and puts the price together. On Checkatrade, a customer whose job was verified rated us 10 out of 10. Nothing is charged for the site visit or for the itemised written quote. Before you book a visit in Spetisbury, you can read our customers' Google reviews, word for word, on our reviews page.

Most repairs in Spetisbury need no application at all. What decides whether a change to the outside of your house does is who the council is, whether a conservation area or a listing applies, and whether the place sits in a protected landscape.