If you're doing electrical installation work in your home or garden in England or Wales, you must follow the building regulations. It's recommended to hire an installer who is registered with a competent person scheme (a registered competent person’) who can self-certify that the work meets the required standards.

If your proposal for planning permission or building regulations approval is solely for extensions or alterations to a disabled person’s house to improve access, safety or comfort then you are exempt from paying a planning or building control fee. Additionally, if you are providing means of access for disabled persons to public buildings you are exempt from any fee.

Note that for building regulations approval, you will only be exempt when applying to a local authority building control body.

Planning permission is not required for moving internal walls in a flat.If the building is a listed building, you may require listed building consent.

Removing a load bearing wall will require building control approval as it is altering the structure of the property. You will be required to provide a report from a structural engineer who will provide structural calculations.

Work on internal walls may also affect fire escape routes, ventilation, drainage or electrics. These should be considered during the design process and work should be carried out by a member of the competent person scheme where possible.

Work to refit a bathroom with new units and fittings does not generally require building regulations approval, although drainage or electrical works that form part of the refit may require approval under the building regulations.

If a bathroom is to be provided in a room where there wasn't one before, building regulations approval is likely to be required to ensure that the room will have adequate ventilation and drainage, and meet requirements with respect to structural stability, electrical and fire safety.

A roof window (or skylight) is fitted flush within the slope of a roof, while a dormer projects outward, creating additional headroom and floor space.  

Both can be installed under permitted development but must meet specific size and position limits to qualify.  

Also consider building regulations for a new dormer, find out more on Planning Portal  

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