The best flat roof material for most Edinburgh homes comes down to three real contenders: GRP fibreglass, traditional felt and EPDM rubber. PVC single-ply shows up occasionally too. The right one depends less on the size of your roof than on its shape, how long you plan to stay in the house, and when in the year the work happens.
Every price below is a general guide, not a quote. Deck condition, access and the specifics of your roof can move the real number, so use these figures to compare the materials against each other, not to budget your job.
Key takeaways
- GRP suits awkward shapes, balconies and walk-on areas, but needs dry conditions and won't cure reliably below about 5°C.
- Felt is the cheapest to install and the cheapest to replace again in 15 to 20 years. On a roof you'll own for decades, that trade-off usually loses to EPDM.
- EPDM comes in wide sheets (3.05m and 6.10m), so many small rectangular roofs go down as one piece with fewer joins to fail. It's usually the best lifetime-cost option on a simple shape.
- PVC single-ply is a solid mid-range option but often prices poorly on small roofs, since the welding equipment is needed whatever the area.
- Switching to a different covering type, rather than a like-for-like recover, is more likely to need a Scottish building warrant. Worth knowing before you pick.
Comparing the Materials
GRP Fibreglass
Roughly £80 to £130 per m² installed. Lasts 25 to 40 years.
Laid wet as a liquid resin, then cured into a rigid, seamless surface. That makes it the strongest choice for awkward shapes, roof junctions, balconies and anywhere that gets walked on. It needs dry weather and time to cure between coats, and standard resin won't cure reliably below about 5°C, so winter installs need care.
Because it cures rigid, a small crack or star fracture can appear if the deck moves underneath it, and a repair means matting and resin over the damaged patch rather than a quick patch job, so it's worth getting any deck movement sorted before you commit to GRP. The finish is smooth and uniform, and it's the material of choice for roofs that double as a walked-on terrace or balcony. Installation involves resin fumes, which usually clear within a day or two.
Traditional Felt
Roughly £80 to £120 per m² installed. Lasts 10 to 20 years.
The lowest upfront cost by a clear margin, and a sensible choice on a garage or another straightforward roof where a shorter lifespan is acceptable. Torch-on felt is miserable to lay in rain, worth factoring in for winter jobs. Over a 30-year ownership period, felt usually loses out to EPDM on total cost because you're paying for two installs instead of one.
Felt's multiple layers and seams are its weak point. It's the easiest of the three to patch cheaply if a seam lifts or a small puncture appears, but those same seams are where most felt failures start, so it needs more regular checking than GRP or EPDM. Torch-on installation involves a naked flame and a noticeable smell during the work, which is worth flagging to neighbours on a terraced or tenement job.
EPDM Rubber
Roughly £50 to £110 per m² installed. Lasts 30 to 50 years.
A single-ply rubber membrane, supplied in wide sheets, so many smaller rectangular roofs can be covered in one continuous piece with fewer joins to fail. On a simple shape this is usually the best lifetime-cost option: on a 25m² roof, EPDM at £80 per m² works out at around £2,000, or roughly £40 to £67 a year over 30 to 50 years, against felt at £60 per m² working out at around £1,500, or roughly £75 to £100 a year over 15 to 20 years.
It's also the easiest of the three to repair. A puncture or split can usually be patched with a liquid or tape repair kit without specialist tools, and the rubber stays flexible over time rather than going brittle, so it copes well with a bit of deck movement. Installation is a cold process with no flame and minimal smell, which makes it the least disruptive of the three to fit.
What About PVC Single-Ply?
Roughly £80 to £150 per m² installed. Lasts 35+ years. A solid mid-range option, but small roofs often price poorly with it because the hot-air welding equipment is needed whatever the area. Worth pricing if your roof is large enough to spread that setup cost, otherwise GRP or EPDM usually make more sense. Like EPDM it's flexible and copes well with movement, and welded seams can be re-welded for a repair, though this needs the same specialist equipment as the original install.
Quick Comparison
Cost per m² is a general guide only and depends on access, deck condition and the roof's shape.
Which One for Your Job
If the roof is a simple rectangle and you're staying in the house long-term, EPDM usually wins on lifetime cost and is the easiest to maintain. If it's a garage or a short-term fix, felt keeps the upfront number down, just expect to keep an eye on the seams. If the shape is awkward, has upstands, or gets walked on, GRP is the one built for that, provided the deck underneath is solid. PVC earns its place mainly on larger, simpler roofs where the welding setup cost is spread further.
One Thing to Check Before You Choose
Recovering in the same general covering type can fall under exempt work in Scotland. Switching to a different covering type, for example moving from felt to GRP, is more likely to need a building warrant from City of Edinburgh Council or your Lothian council. Worth a quick check before you commit to a material, not after. If you're weighing up a full strip and re-roof rather than just a recover, our full roof replacement service covers that in more detail.
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