Downpatrick at a glance
- Postcode districts
- BT30
- Population
- about 10,507 (GeoNames)
- Council area
- Newry, Mourne and Down District Council
- Building approval
- Newry, Mourne and Down District Council building control
- Nearest main town
- Lisburn, about 19 miles
- Guide price region
- Northern Ireland (−12% on West Midlands rates)
What makes a good extension roof in Downpatrick?
Ponding against the house wall is a common reason for replacing an extension roof in Downpatrick. When the deck dips near the wall or the fall runs the wrong way, water sits against the abutment and eventually gets in. A new roof with corrected falls moves the water to the gutter.
In a town like Downpatrick, flat roofs are commonly found on terraced streets with flat-roofed rear kitchens and bathrooms or lock-up garage blocks on estates. Northern Ireland averages roughly 1,150 mm of rain a year, spread over many wet days, so a roof that sheds water quickly to clear outlets lasts far longer than one that holds puddles.
How much does a new extension roof cost in Downpatrick?
At Northern Ireland guide rates, a 20 m² extension roof in EPDM with a new deck and insulation comes to £2,450–£4,300 including VAT. 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 | £2,450–£4,300 |
| Extension (20 m²), GRP, new deck + insulation | £2,650–£4,750 |
| Extension (20 m²), EPDM, insulation + 1 rooflight upstand | £2,650–£4,600 |
| Single garage (18 m²), EPDM rubber | £1,400–£2,450 |
Why does water pond or leak where the extension meets the house?
Usually because the fall runs the wrong way, the abutment detail has failed, or the roof has sagged close to the wall. The junction with the house is the most common leak point on an extension roof.
If the roof falls towards the house, or the deck dips near the wall, water sits against the upstand and finds any weakness in the flashing above. Older roofs often have the felt simply turned up the brickwork with no cover flashing, or a flashing that has pulled out of its joint. A patch will not change a fall. We re-firr or use tapered insulation so water runs away from the wall, then form a new upstand, usually 150 mm above the finished roof, with a flashing chased into the mortar joint.
Rooflights and lanterns are the other weak point. A lantern needs a properly built kerb with the membrane dressed up and under its frame. We rebuild rooflight upstands within the roof job; we do not supply the lantern itself. Our guide to ponding water explains the causes in more depth.
What's included?
- Free survey of the roof, abutment and room below
- New abutment upstand and flashing, plus rebuilt rooflight kerbs
- Staged strip-out so the room stays weathertight
- New deck, vapour control layer and warm-roof insulation
Building control in Northern Ireland
In Northern Ireland, Technical Booklet F1 sets roof insulation at 0.18 W/m²K when a roof over a heated room is renovated or newly built, where that's feasible. The district council's building control should be contacted before work starts, and we prepare the details it asks for. More on the rules.
Which nearby areas do we also cover?
Extension and kitchen roofs in Downpatrick: questions
Do you cover Downpatrick?
Yes. Downpatrick is part of our County Down coverage, including postcode districts BT30. 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 Downpatrick?
Where the work needs approval it goes to Newry, Mourne and Down District Council building control. 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 Downpatrick?
£2,450–£4,300 for a 20 m² extension roof in EPDM with a new deck and insulation, at Northern Ireland guide rates including VAT. The fixed price comes after a free survey for new and replacement roofs.
Can you keep my existing roof lantern?
Often, if the lantern itself is sound. We lift it, rebuild the kerb, dress the new membrane up the upstand and refit the lantern.
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.