Harrow at a glance
- Postcode districts
- HA3, HA1, HA2, HA7, HA5, HA8, HA6
- Council area
- London Borough of Harrow
- Building approval
- London Borough of Harrow building control, or a registered building control approver
- Guide price region
- London (+20% on West Midlands rates)
What do block and HMO roofs in Harrow need?
Leaseholders in Harrow want to see where their money goes. Our itemised quotes show each element of the job separately, including scaffold, insulation and provisional sums for hidden defects, which makes them easier to share and compare when the freeholder or agent is consulting on the work.
In a town like Harrow, flat roofs are commonly found on shops with flat-roofed stores below flats above or mansard and dormer loft conversions. The Thames basin is one of the drier parts of Britain at roughly 730 mm of rain a year, but summer heat is the bigger test here: dark membranes on south-facing roofs swing a long way in temperature.
How much does a block or HMO roof cost in Harrow?
At London guide rates, a 150 m² block-of-flats roof in felt with insulation and scaffold comes to £18,650–£32,650 including VAT. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Block of flats (150 m²), felt + insulation + scaffold | £18,650–£32,650 |
| Commercial roof (100 m²), single-ply + insulation | £15,900–£26,150 |
Do fire and insulation rules affect block roofs?
Yes. Where a roof is close to a boundary, building regulations limit which coverings can be used, and the build-up should carry a suitable external fire classification such as BROOF(t4); in England this is covered by Approved Document B.
BROOF(t4) applies to a tested build-up, so we check that the manufacturer's classification covers the deck, insulation and membrane actually being installed, not just the membrane name. Where the roof crosses a separating or compartment wall, the fire-stopping detail is kept intact.
Re-covering more than half of a roof over heated flats usually triggers the thermal element rules, so the insulation is upgraded towards the renovation U-value where feasible: 0.16 W/m²K for dwellings in England and Wales. We handle building control where it is needed. See building regulations and warm vs cold roofs.
What's included?
- Free survey and fixed, itemised written quote
- Quotes laid out to support leaseholder consultation
- Written workmanship guarantee, with manufacturer guarantees registered where the system allows
- Building control and insulation upgrades handled where needed
Building regulations in England
Replacing more than half of a flat roof over a heated room usually counts as renovating a thermal element, so the roof is insulated to around 0.16 W/m²K where that's technically and economically feasible, and the work is notified to building control: the council or a registered building control approver, unless a registered competent person self-certifies it. A roof on a new extension is built to 0.15 W/m²K. Patch repairs, and most unheated detached garages, don't trigger the upgrade. Structural changes, or a new covering that adds 15% or more to the roof's weight, also need approval. More on the rules.
Which nearby areas do we also cover?
Flats, HMOs and block roofs in Harrow: questions
Do you cover Harrow?
Yes. Harrow is part of our London coverage, including postcode districts HA3, HA1, HA2, HA7, HA5, HA8 and 1 more. Surveys and roofs are carried out by vetted roofing teams working under S&K Property Investments and Improvement Ltd.
Who checks building regulations for a flat roof in Harrow?
Where the work needs approval it goes to London Borough of Harrow building control, or a registered building control approver. We tell you at the survey whether your job needs it and deal with the paperwork as part of the quote.
How much does a block or HMO roof cost in Harrow?
£18,650–£32,650 for a 150 m² block-of-flats roof in felt with insulation and scaffold, at London guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Can a block roof be replaced in phases?
Yes. Larger roofs can be split into sections over one or more budget years, with each phase priced separately and each section left watertight before the team leaves site.
Do you run the Section 20 consultation?
No. The freeholder or managing agent runs the consultation; we provide itemised written quotes that can be shared with leaseholders and answer technical questions passed on through the agent.