Flat roofing in Wareham

Small flats behind a parapet. Common on the older buildings in town. They drain to one outlet, often internal, and there is no margin in the design: block the outlet and the roof becomes a tank, and the first thing anybody notices is damp at the head of a wall. We re-form the outlet, look at the coping and any cavity tray, and dress a lead cover flashing into a chase at the abutment rather than trusting a bead of mastic. Where the original covering is lead, a re-lay in shorter bays often solves a split without changing what the building looks like.

Back additions and outshots. Older houses grew outwards, so there is usually a low roof over a kitchen, a bathroom or a passage. Where the deck is sound, EPDM rubber goes down as one sheet with bonded seams, and GRP fibreglass suits one with kerbs, steps or an awkward corner because it is laid wet and forms the upstands and edge trim in one piece.

Garages and extensions on the newer estates. Mostly felt built up in three layers with a mineral cap sheet on top, over plywood, OSB or chipboard. Chipboard that has been wet swells and stops holding a fixing, so it comes off. A modern torch on system suits a big plain span, and single ply welded at the laps suits a large or complicated one.

Falls, insulation and the damp that never rained. Firrings create the falls over the joists, and where there are none you get ponding and standing water working on every lap and seam. Tapered insulation fixes a fall from above when the joists cannot be touched. A warm roof puts PIR over the deck on a vapour control layer laid first, so the timber stays clear of the dew point by design. A cold roof leaves the insulation between the joists and has to be ventilated, or condensation and interstitial damp ruin the decking. BS 6229 sets out both.

The rest of the detail. Blisters and bubbles, a split or crack in a tired covering, and a lifted or failed seam are the everyday repairs. At the perimeter, the edge trim, the drip and the apron into the wall. Openings mean a rooflight, a lantern or a Velux on a formed kerb, plus any soil pipe or vent pipe through the deck. Then the rainwater outlet and the downpipe under it, with the hopper and gutter sized for what the roof actually sheds.

No rate per square metre, because the square metres are the easy part and what is under the covering is what decides the job.

Getting to it. A back addition reached only through a passage, a garage on a post war estate and a bungalow extension are three different jobs before a single board comes up. A garage or a single storey extension will often come off a tower, anything above a two storey wall wants a scaffold, and the platform has to stand while the deck is open rather than for an afternoon. The work at height rules are why it is a priced line rather than something folded into a rate.

The deck under the covering. A sound deck can be re-covered. Chipboard that has been wet for years, or ply that gives underfoot, has to come off and be replaced, and you cannot tell which you have from the ground or from a photograph. We lift a corner before quoting, because the deck is the single biggest swing in the price.

The falls, and where the water is meant to go. Most flat roofs that fail were never laid to a fall, or the fall runs at an outlet that has since been blocked or built over. Correcting it with firrings is more work than laying a membrane and it is the difference between a roof that lasts and one that ponds. Upstands, edge trims and each outlet are priced one at a time, because that is where the hours and the leaks both are.

Comparing quotes? Ask which system is being quoted and how many layers, whether the deck is being renewed or covered over, whether the falls are being corrected with firrings, how the upstands, outlets and edge trims are detailed, and whether the scaffold and the skip are in the price. Two quotes for the same job are usually two different jobs.

We cover Wareham town, Northport, Stoborough, Sandford and the BH20 addresses around them, with Dorset Council as the planning authority. You are dealing with Bournemouth Roofing & Building, the trading name of Bournemouth Roofing & Building Ltd, registered in England and Wales, company number 15471719, which you can look up in a minute. Thomas Hannen's business, and he is the one who comes out to price the job, not a salesman. A verified customer's 10 out of 10 on Checkatrade. The visit and the written quote are both free.