There is no single legal definition of "habitable room", as its use and meaning are subject to context. Generally, a habitable room is a space in a building that is designed for people to live, sleep, or spend extended periods of time in, but does not include bath or toilet facilities, corridors or utility rooms.

In most cases, yes - planning permission is required to operate a business from your garage. This is because the use would no longer be purely domestic, and the garage would be considered to have changed use from residential (Class C3) to a business-related use, which requires planning consent.

Adding an internal wall will not require planning permission or building control approval in most cases. If the building is listed, then you may require listed building consent to make a major alteration to the house.

Any work completed should adhere to building regulations, ensuring fire routes, electrics and ventilation are considered.

National planning regulations allow certain alterations to be made to a property without requiring planning permission; these are known as permitted development rights. In some cases, local authorities may remove or restrict these rights for specific types of development that would otherwise be allowed. This is achieved through the use of Article 4 Directions, which are intended to protect the character, heritage, and appearance of designated areas.

If your local planning authority has issued an Article 4 Direction, some of your permitted development rights may no longer apply. As a result, you may need to submit a planning application for works that would not normally require one.

You can check whether an Article 4 Direction affects your property by visiting your local authority’s website.

Inserting new windows which look similar to those previously used in the house will often not require planning permission. Some rules apply to new additions, for example if they are on an upper-floor side elevation they must be obscure glazed and non-opening or more than 1.7 metres above the floor.

Installing a new bay window on the front elevation would require planning permission as it is classed as a forward extension.

If you live in a listed building or conservation area you should contact your local planning authority.

 Any new openings will have to comply with building regulations, this may impact thermal heat loss, structure, ventilation and fire safety.

You can use a member of a competent person scheme to complete any work, this will ensure that the work is completed in-line with regulations.

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