Reducing heat loss

Reducing heat loss involves insulating or upgrading the elements of the building fabric – such as walls, floors, roof, windows and doors – to reduce the energy needed for heating. These measures should be considered first in any building retrofit plan.

Typical measures include:

Loft insulation
Cavity wall insulation
External / internal wall insulation (for solid walls)
Ground floor insulation
Replacing or upgrading windows and external doors

If, as a result of energy-efficiency improvements, a building is being made more air-tight, it may also be necessary to install a ventilation system to manage condensation and air quality without excessive heat loss.

Advantages

Insulation will improve the comfort of your home and save you money on fuel bills. The Energy Saving Trust estimate that a typical loft insulation on a detached house would cost £290 and, over a 40-year lifespan, result in savings of £840 (paying back after 14 years) and 3200kg CO2. Cavity Wall Insulation on a detached house will cost £725, but result in annual savings of £255 and (a pay-back period of less than three years), and reduce CO2 emissions by 1040kg each year.

Effects on wildlife

Installation of external wall insulation can result in the loss of nesting places for swifts and other bird and bat species in the eaves and behind bricks. This advice note by the Swifts Local Network sets out a number of actions you can take to address this. These include installing ‘swift bricks’ within external walls, and attaching swift nesting boxes, in a shaded location – Swift Conservation and Ealing Wildlife Group’s Saving Our Swifts project provides further advice on this.

Does it need planning permission?

Listed Building Consent is likely to be required for any change to a listed building. For other buildings, planning permission is not usually required for any works that do not alter the external appearance of the building.

As such, the only insulation measure likely to require Planning Permission would be external wall insulation. External insulation often raises concerns due to the different types of material used and the expansion of the external envelope of the building. This may often appear visually jarring, particularly where there is consistency in design of neighbouring buildings.

Where a property is detached or appears unique in a streetscape, the Council is unlikely to object to a planning application for external insulation unless the property is of designated architectural merit (listed, within a conservation area). Should the property be semi-detached or within a terrace, alternative forms of retrofitting will first be encouraged. Should no other retrofitting measures prove feasible, then householders are encouraged to engage with the Council’s pre-application advice service.

Further details on replacement windows and doors may be found within the Council’s Residential Extension Guidelines (REGs); but generally, a like-for-like replacement (material, style and colour) would not require permission.