Flat roofs have a bad reputation in Charlestown, and it's deserved, because most of them were covered in felt. Felt has joints, joints fail, and the typical felt roof on an extension or garage in Charlestown, PL25 is leaking within fifteen years. EPDM changes that. It's a synthetic rubber membrane supplied in sheets large enough to cover most domestic flat roofs in one piece, so there are no seams to fail. It stays flexible from well below freezing to the hottest days we get in Cornwall, which means it moves with the building instead of cracking, and manufacturers rate it at fifty years.
Where we fit EPDM in Charlestown
EPDM is our first choice for the flat roofs you find on houses across Charlestown: rear and side extensions, garages, flat-roofed dormers, porches, bay window roofs and balconies. It's also what we use for the flat sections on larger buildings in Charlestown, PL25 where a single-ply system makes sense. For roofs that will be walked on regularly, or that have a lot of complicated upstands and penetrations, GRP fibreglass can be the better choice, and we'll tell you which suits yours rather than selling you the one we happen to have on the van.
How we install an EPDM roof
- Strip and inspect. The old covering comes off and we look at the deck. Soft, delaminated or rotten boards are replaced rather than covered over. Covering a wet deck traps the moisture and rots it, which is the commonest cause of a new flat roof failing early.
- Falls. Flat roofs shouldn't be flat. We check the fall to the outlets and correct it with firring pieces or tapered insulation if water has been ponding.
- Insulation. A warm roof build-up, with rigid insulation board over the deck, is what Building Regulations expect when a flat roof is renewed, and it's where most of the heat was going. It also stops the condensation that cold flat roofs in Charlestown suffer from.
- Membrane. The EPDM sheet is fully bonded to the deck with the manufacturer's adhesive, not laid loose and weighted. Fully adhered roofs don't flap, don't billow in wind and don't let water track underneath.
- Details. Upstands, outlets, pipes and corners are formed with the proper preformed corners, cover strips and trims. This is where a cheap job goes wrong, so it's where we spend the time.
- Edges. uPVC or aluminium edge trims finish the perimeter cleanly and direct water into the gutter.
Roof lanterns, windows and extras
Most of the extensions we roof in Charlestown now have a roof lantern or flat-roof window, and EPDM takes them well: the membrane is dressed up the kerb and sealed with the system's own trims. We fit the lantern or window at the same time as the roof so there's one contractor responsible for the whole thing. Green roof build-ups, solar panel fixings and new outlets and downpipes can all be added while we're there.
EPDM versus GRP, felt and asphalt
Felt is the cheapest on the day and the dearest over time, with a life of ten to fifteen years and joints that fail. We'll fit it if you ask, but we rarely recommend it. Asphalt is heavy, cracks as it ages and is rarely used domestically now. GRP fibreglass is excellent and we fit a lot of it; it's harder-wearing for roofs you walk on and better around complicated shapes, but it's less forgiving to lay and costs a little more on a simple roof. EPDM wins on simple to moderate roofs, on flexibility, on speed and on value, which is why it covers more of the flat roofs we do in Charlestown, PL25 than anything else.
Guarantees and paperwork
We install manufacturer-approved EPDM systems, and the membrane comes with the manufacturer's own warranty on top of our workmanship guarantee. You'll get the paperwork with the quote, not after the job, so you can see what's covered before you say yes. If Building Control involvement is needed for insulation on a renewed roof, we handle the notification.
Signs your flat roof in Charlestown is on its way out
Felt flat roofs in Charlestown rarely fail dramatically. They go gradually, and the signs are easy to miss until the ceiling below starts to stain. Ponding water that sits for more than a day or two after rain means the falls have gone or the deck has sagged. Bubbles and blisters in the felt mean moisture is trapped underneath. Cracks along the joints and at the edges, especially where the felt turns up against a wall, are where the leaks will start. A spongy feel underfoot means the deck is rotting. Moss and vegetation growing in the surface means water is sitting there permanently. Inside, a damp patch on the ceiling, a musty smell in the room below or mould in the corners all point upwards. If a flat roof in Charlestown, PL25 is showing two or more of these, patching it is money wasted and a new EPDM roof is the sensible answer.
How long the job takes and what it costs
A single garage or a small extension roof in Charlestown is a one-day job: strip in the morning, new deck and insulation by lunchtime, membrane bonded and trimmed by the end of the afternoon. Larger extensions and roofs with lanterns or several outlets take two days. The cost depends on the area, the amount of deck that needs replacing, whether insulation is included, and the number of details such as outlets, upstands and rooflights. We quote in writing after seeing the roof, with the deck replacement priced as a provisional item so you only pay for the boards we actually have to change.
Flat roofing across Charlestown and Charlestown, PL25
Charlestown Roofing is based in Charlestown and covers the whole of Charlestown, PL25. A single garage or extension roof is usually one to two days from strip to finish. We give written quotes after seeing the roof, and we photograph the deck, the insulation and the finished details so you have a record of what's under the rubber.