Planning permission is not normally required for fitting insulation (where there is no change in external appearance).

However, if the building is listed or is in a conservation area you should consult your local planning authority.

Insulation has to comply to the relevant building regulations both when installed during construction or when fitted retrospectively.

It is advisable to contact an installer who can provide the necessary advice, preferably one who belongs to the relevant Competent Person Schemes.

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Without loft insulation you could be losing as much as a third of your heating costs through your roof.