Yes, under permitted development, a new dormer must not be higher than the existing highest part of the roof. It should also have materials that are in similar appearance to the existing roof. Additional limits apply in conservation areas and on listed buildings. Read about planning permission for loft conversions on Planning Portal
A 'listed building' is a building, object or structure in the UK that has been considered as of national importance in terms of architectural or historic interest and included on a register called the List of Buildings of Special Architectural or Historic Interest.
Buildings are listed to help protect the physical evidence of our past, including buildings, which are valued and protected as a central part of our cultural heritage and our sense of identity. Historic buildings also add to the quality of our lives, being an important aspect of the character and appearance of our towns, villages, and countryside.
There are three listing grades:
- Grade I - Buildings of exceptional interest
- Grade II* - Particularly important and more than special interest
- Grade II - Buildings of special interest, warranting every effort being made to preserve them (this is the most common)
If you live in a listed building it means you cannot demolish or alter the building in a way that changes its character without Listed Building Consent.
The principal elevation is the most visible or prominent side of a structure, typically facing a street or public area. While often considered the 'front' of the building, it may not always contain the main entrance. There can only be one principal elevation of a house.
Foundations are required to carry and distribute the load of the building safely. Therefore, all buildings should have adequate foundations. The factors that need to be considered when designing a foundation are:
It is advisable to contact a structural engineer or speak to a building control body about plans for new foundations.
Read more about foundations for extensions
Merging two flats into one, commonly known as amalgamation is likely to require planning permission as it will impact the local planning authorities housing supply. The council’s views on this will vary from council to council. It is recommended that you contact your local planning authority to understand their position.
If you do not need to apply for planning permission then you can apply for a lawful development certificate to prove that the change is lawful.
Building regulations will be required if there are physical works taking place as part of the amalgamation, this may include removing walls or changing electrics. Visit the relevant common projects on our site for more information.
You will not need planning permission if a new or replacement driveway of any size uses permeable (or porous) surfacing which allows water to drain through, or if the rainwater is directed to a lawn or border to drain naturally.
If the surface to be covered is more than five square metres planning permission will be needed for laying traditional, impermeable driveways that do not provide for the water to run to a permeable area.
This guidance applies to houses, there are different rules for flats and maisonettes, converted houses, new houses or areas where there permitted development rights may be restricted.
Read about paving your front garden
You may need to consider if a dropped kerb is required, largely dropped kerbs are not a planning matter but you will need to apply to your local council.
Find out more about dropped kerbs