Havant at a glance
- Postcode districts
- PO9
- Population
- about 45,574 (GeoNames)
- Council area
- Havant Borough Council
- Building approval
- Havant Borough Council building control, or a registered building control approver
- Nearest main town
- Portsmouth, about 6 miles
- Guide price region
- South East (+10% on West Midlands rates)
Why upgrade to a warm roof in Havant?
Landlords with flats and HMOs in Havant sometimes hear from tenants about cold top-floor rooms and black mould on ceilings. A warm roof upgrade during re-roofing tackles both the heat loss and the condensation behind the mould, and helps keep the roof timbers dry.
In a town like Havant, flat roofs are commonly found on 1960s and 1970s link-detached houses with flat-roofed garages and porches or newer estates where the first extension roofs are now being replaced. Much of the South East sits in the drier Thames catchment at roughly 730 mm of rain a year, so the usual failures are at joints, upstands and outlets rather than from sheer volume of rain.
How much does a warm roof upgrade cost in Havant?
Guide price in Havant: £3,100–£5,350 for a 20 m² extension roof in EPDM with a new deck and insulation, including VAT at South East rates. The fixed price comes after a free survey for new and replacement roofs.
| Job | Guide price inc VAT |
|---|---|
| Extension (20 m²), EPDM, new deck + insulation | £3,100–£5,350 |
| Extension (20 m²), EPDM with sedum green roof | £4,850–£8,900 |
Do I have to insulate my flat roof when I replace it?
Usually, yes, if the roof is over a heated room and you are replacing more than half of its covering. In England, Wales and Northern Ireland, that counts as renovating a thermal element, so the roof should be upgraded to the renovation standard where that is technically, functionally and economically feasible.
The rules don't usually apply to patch repairs, or to an unheated, detached garage. The target U-value depends on where you live:
| Nation | Roof renovation target |
|---|---|
| England | 0.16 W/m²K (homes), 0.18 (non-domestic) |
| Wales | 0.16 W/m²K |
| Scotland | Section 6 framework, with a domestic benchmark of 0.12 W/m²K pursued as far as reasonably practicable |
| Northern Ireland | 0.18 W/m²K |
A new extension roof has a tighter target than a renovation: 0.15 in England and 0.13 in Wales. The economic test in England's guidance is a simple payback within 15 years. We handle building control or building standards where it is needed. The building regulations page sets out the approval routes in each nation.
What's included?
- Rigid insulation boards sized to the U-value target
- New waterproofing, with a written workmanship guarantee
- Survey of the deck, joists and existing insulation
- Upstands, trims and kerbs reset to the new roof level
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?
- Emsworth · 2 mi
- Waterlooville · 3 mi
- Hayling Island · 5 mi
- Portsmouth · 6 mi
- Gosport · 8 mi
- Fareham · 8 mi
Warm roof insulation upgrades in Havant: questions
Do you cover Havant?
Yes. Havant is part of our Hampshire coverage, including postcode districts PO9. 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 Havant?
Where the work needs approval it goes to Havant Borough Council 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 warm roof upgrade cost in Havant?
£3,100–£5,350 for a 20 m² extension roof in EPDM with a new deck and insulation, at South East guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
How thick does flat roof insulation need to be?
It depends on the insulation product and the U-value target. With common PIR boards, meeting a renovation target usually means well over 100 mm. Thinner, higher-performance boards are available where height is tight.
Is there VAT relief on flat roof insulation?
Don't count on it. Insulation fitted as part of a roof replacement is usually treated as part of a single standard-rated job. Check your own case with HMRC guidance or an adviser.