Redbridge at a glance
- Postcode districts
- IG1, IG2, E12, IG3, E20, IG4, IG5, IG6
- Council area
- London Borough of Redbridge
- Building approval
- London Borough of Redbridge building control, or a registered building control approver
- Guide price region
- London (+20% on West Midlands rates)
What makes a good extension roof in Redbridge?
Extension roofs in Redbridge are often replaced because the original was built cheaply: thin chipboard decks, little or no insulation and felt turned up the wall without a proper flashing. Twenty or thirty years on, those weaknesses show up as leaks at the back wall and a cold, damp ceiling.
Around Redbridge, flat roofs are common on mansard and dormer loft conversions and on Victorian and Edwardian terraces with flat-roofed back additions. 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 new extension roof cost in Redbridge?
For Redbridge we use London rates: £3,350–£5,850 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.
| Job | Guide price inc VAT |
|---|---|
| Extension (20 m²), EPDM, new deck + insulation | £3,350–£5,850 |
| Extension (20 m²), GRP, new deck + insulation | £3,600–£6,450 |
| Extension (20 m²), EPDM, insulation + 1 rooflight upstand | £3,600–£6,300 |
| Single garage (18 m²), EPDM rubber | £1,900–£3,350 |
Which flat roof system suits a kitchen extension?
On a plain rectangular extension, EPDM rubber is a strong, quiet choice that can often be laid in one sheet. It handles the slight movement between an extension and the house well.
Where the roof has a lantern, several rooflights or an internal corner, GRP fibreglass forms neat, rigid details around each one. Torch-on felt is a proven layered system and keeps costs down, though near timber cladding or at fragile junctions we may prefer a cold-applied method. If the extension is overlooked from upstairs windows, a sedum green roof is worth considering, provided the structure can take the extra load.
Whatever the membrane, the insulation sits above the deck as a warm roof. Our warm vs cold roof guide explains why.
What's included?
- Staged strip-out so the room stays weathertight
- New deck, vapour control layer and warm-roof insulation
- Falls set away from the house wall
- Building control handled where needed, and a written workmanship guarantee
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?
- Barking and Dagenham · 3 mi
- Newham · 3 mi
- Waltham Forest · 4 mi
- Greenwich · 5 mi
- Havering · 5 mi
- Tower Hamlets · 6 mi
Extension and kitchen roofs in Redbridge: questions
Do you cover Redbridge?
Yes. Redbridge is part of our London coverage, including postcode districts IG1, IG2, E12, IG3, E20, IG4 and 2 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 Redbridge?
Where the work needs approval it goes to London Borough of Redbridge 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 new extension roof cost in Redbridge?
£3,350–£5,850 for a 20 m² extension roof in EPDM with a new deck and insulation, at London guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
How do I know my extension roof needs replacing rather than repairing?
Repeated leaks, a soft deck, wet insulation or widespread cracking point to replacement. A single defect on a dry, sound roof can usually be repaired.
Do I need my neighbour's permission to replace an extension roof?
Not for a like-for-like re-cover in most cases. The Party Wall Act in England and Wales can apply if the work raises or cuts into a shared wall, so we flag that at survey.