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Before you start
What changes on the outside of your house, and what to check before the work begins.
Permissions
Planning permission
Whether you need it depends on where you live and how much the house changes in appearance. Check with Leeds City Council if you are in a conservation area, live in a listed building or a flat, or plan to cover a brick front with render. Brick slips can help where keeping the look matters.
Building Regulations
Insulating most of a wall normally counts as renovating a thermal element, so the finished wall has to meet Building Regulations for insulation. Ask at the survey how sign-off will be handled on your job.
What changes on the house
- Sills. Replaced or extended so they still project past the new wall.
- Pipes and gutters. Downpipes and waste pipes taken off and refitted on longer brackets.
- Fittings. Lights, alarm boxes, satellite dishes and meter boxes moved out to the new face.
- Vents. Air bricks and extractor outlets extended through the insulation.
- Flues. Boiler flues extended by a Gas Safe registered engineer.
- Roof edge. Eaves and verges extended where the roof would not overhang the new wall.
- Base of the wall. The system starts above the damp-proof course, with a plinth detail below.
Get these sorted first
Damp
Leaking gutters, a bridged damp course or high ground outside must be fixed before a wall is insulated.
Cracks and movement
Old, stable cracks can be repaired. Cracks that are still widening need a structural engineer first.
Funding
Government-backed schemes sometimes help eligible households with insulation. The schemes change, so check what is open now.
More questions
Who moves my boiler flue?
Gas appliance flues must only be altered or extended by a Gas Safe registered engineer. We flag any flues at the survey so the work can be booked in at the right point.
Will my roof need altering?
Sometimes. The roof edge needs to overhang the new, thicker wall so rain is thrown clear. If it does not, the eaves or verges are extended, or a trim is fitted. We check this at the survey.
What if my neighbour is not having it done?
That is common. On a semi or terrace, the insulation stops at the party line with a neat edge. Where a wall is on the boundary itself, the extra thickness would overhang their land, so you would need their agreement first.
Do I need more ventilation afterwards?
A better-insulated house is often more airtight. Keep trickle vents open and extractor fans working in kitchens and bathrooms so moisture from daily life can still get out.
Book a survey
We check all of this on one visit.
Not sure what applies to your house?
The survey covers all of it, and it is free.