Flat RoofingContractors

Upgrades

Warm roof insulation upgrades in Lancing

Converting a cold flat roof to a warm roof is a sensible upgrade for many flat roofs in Lancing. The old covering is stripped, the deck is checked, and a vapour control layer, rigid insulation and new waterproofing go on top, with trims and upstands raised to suit.

Foil-faced PIR insulation boards laid over a vapour control layer to make a warm flat roofComputer-generated example image

Lancing at a glance

Postcode districts
BN15
Population
about 18,692 (GeoNames)
Council area
Adur District Council
Building approval
Adur District Council building control, or a registered building control approver
Nearest main town
Worthing, about 2 miles
Guide price region
South East (+10% on West Midlands rates)

Why upgrade to a warm roof in Lancing?

Small commercial buildings in Lancing with large flat roofs can lose a lot of heat through them. Where the roof is being replaced, upgrading the insulation at the same time is required in most cases and helps reduce running costs for the occupier.

In and around Lancing, flat roofs are typically found on low-rise post-war blocks of flats, and on 1960s and 1970s link-detached houses with flat-roofed garages and porches. 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 Lancing?

For Lancing we use South East rates: £3,100–£5,350 is the guide for a 20 m² extension roof in EPDM with a new deck and insulation, VAT included. The fixed price comes after a free survey for new and replacement roofs.

JobGuide 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

How long does a warm roof last?

The insulation in a warm roof should last for the life of the waterproofing above it, as long as it stays dry. Rigid PIR boards don't settle or slump in the way some loose insulation can.

The waterproofing is what sets the timescale. EPDM is typically quoted at 25 to 50 years, GRP at 20 to 40 years and modern torch-on felt at 15 to 25 years with good specification and care. A warm build-up also helps the deck, because keeping it warm and dry lowers the risk of condensation rot. If the waterproofing fails and water gets into the insulation, the wet boards should be replaced, so leaks need prompt attention. The lifespan guide compares the systems.

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?

Warm roof insulation upgrades in Lancing: questions

Do you cover Lancing?

Yes. Lancing is part of our West Sussex coverage, including postcode districts BN15. 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 Lancing?

Where the work needs approval it goes to Adur District 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 Lancing?

£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.

Can you add insulation over my existing roof without stripping it?

Sometimes, if the existing covering and deck are dry and sound. We will check at the survey and explain the risks, and our overlay or strip guide covers this choice.

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.

Other flat roof work in Lancing

Warm roof insulation upgrades in Lancing: get a fixed price

Free survey and a written fixed quote for replacement and new roofs. No obligation.

Call usGet a guide price