Home insulation: where should you start?

There is no single insulation order that suits every property. The right plan depends on the home’s age, construction, condition, exposure and existing ventilation. Begin with evidence rather than a product: review the Energy Performance Certificate, inspect accessible areas and note where rooms feel cold or draughty.

Fix moisture and defects first

Do not cover a leaking roof, defective rainwater goods, damp wall or decayed timber with insulation. Trapping moisture can damage the building and reduce performance. Older solid-wall homes need particular care because changes to materials and airflow can alter how moisture moves through the structure.

Start with straightforward heat-loss measures

Loft or roof

An accessible, dry loft is often one of the simplest places to improve. Existing insulation may be uneven, compressed or missing at edges. Keep ventilation paths clear and get specialist advice for flat roofs, converted roof spaces, damp or structural concerns.

Draught-proofing

Seal unintended gaps around windows, doors, floors and service penetrations, but never block purpose-provided vents, air bricks, combustion air or drainage openings. Draught-proofing should improve comfort without removing necessary ventilation.

Hot-water cylinder and pipes

If you have a hot-water cylinder, check whether it has suitable insulation. Insulating accessible hot-water pipes can also reduce wasted heat. Follow manufacturer and installer guidance around controls and safety equipment.

Walls and floors need a property-specific approach

Cavity-wall insulation requires a professional assessment of the cavity, exposure and building condition. Solid-wall insulation is more involved and can affect moisture balance, room size, external appearance and junctions around roofs and windows. Ground-floor insulation depends on whether the floor is solid or suspended and whether ventilation beneath timber floors can be maintained.

Plan ventilation at the same time

As a home becomes more airtight, moisture and indoor pollutants have fewer escape routes. An improvement plan should assess extract fans, trickle vents and whole-house ventilation rather than treating ventilation as an afterthought.

Build a sensible sequence

1. Understand the construction and current condition.
2. Repair leaks, damp and defects.
3. Complete low-disruption measures where appropriate.
4. Seek independent advice for walls, floors, roofs and whole-house retrofit.
5. Record products, specifications, installers, guarantees and photographs.