In most cases, any change or additions to the structure of a building will need planning permission. Listed below are some simple guidelines to help you determine whether or not they are applicable to you. The guidelines listed here are not an authoritative interpretation of the law.
The advise given here is for guidance only. If you are in any doubt as to whether the work you intend to carry out requires planning permission, you should consult our planning service for advice. If you build or alter a building without obtaining permission first, you may be forced to correct things at a later date, or even remove works, which could prove very costly.
• Please note that these guidelines apply to houses within the National Park.
• (The term highway includes all public roads, footpaths, bridleways and byways).
• (The term original house means the house as it was first built or as it was on 1st July 1948).
• Volume is calculated from external measurements.
Location - You will need planning permission if the proposed addition is less than 20 metres away from the nearest highway or nearer to that highway than the nearest existing part of the original house.
Height - You will need planning permission if the extension is higher than the highest point of the original house, or more than 4 metres high and is within 2 metres of the boundary of the original house.
Volume - You will need planning permission if the volume of the original house is to be increased by 10% or 50 cubic metres, whichever is the greater.
Any buildings such as garages etc. which are more than 10 cubic metres in volume, wherever they are in relation to the house, are treated as extensions of the house and reduce the allowance for further extensions.
Roof Extensions, Loft Conversions and Dormer Windows - You will need planning permission if you want to build an extension or alter a building which would materially alter the shape of the roof.
Garden sheds, garages, greenhouses, summer houses, swimming pools, sauna cabins, ponds, accommodation for pets or domestic animals, enclosures (including tennis courts) etc.
Location - You will need planning permission if the structure is nearer to a public highway than any part of the original house unless it more than 20 metres away.
Area - You will need planning permission if the structure would cover more than 50% of the land around the original house.
Usage - You will need planning permission if the structure is to be used for commercial purposes. (eg. parking area for a commercial vehicle).
Height - You will need planning permission if the structure is more than 3 metres high or 4 metres high if it has a ridged roof.
Volume - You will need planning permission if the structure has a volume of more than 10 cubic metres.
* Please note: If the structure has a volume of more than 10 cubic metre and is within 5 metres of the original house, it would be treated as an extension and would count against the overall volume entitlement.
Capacity - You will need planning permission if the storage tank has a capacity of more than 3,500 litres.
Height - You will need planning permission if the storage tank is more than 3 metres above ground level.
Location - You will need planning permission if the storage tank is nearer to a public highway than any part of the original house unless it more than 20 metres away.
Fuel Type - You will need planning permission if the storage tank is to be used to store liquid petroleum gas (LPG) or any other type of fuel other than oil.
Ground Area - You will need planning permission if the porch tank is more than 3 square metres.
Height - You will need planning permission if the porch is more than 3 metres above ground level.
Location - You will need planning permission if the porch is less than 2 metres away from the boundary of a dwelling or a highway.
Listed Buildings - You will need planning permission if the structure is within the curtilage of a listed building.
Height - You will need planning permission if the structure is over 1 metre high and next to a highway used by vehicles or more than 2 metres high elsewhere.
Hedges and Trees - You will need planning permission only if there is a condition attached to the planning permission for your property which restricts the planting of trees and hedges.
Embanking or Terracing - You will need planning permission if significant embanking or terracing is needed.
Usage - You will need planning permission if it is to be used for commercial purposes. (eg. parking area for a commercial vehicle).
Access - You will need planning permission if it you want to make a new or wider access on a trunk or other classified road.
Highways - You will need special approval from your local highways department if the area is to cross a pavement or verge.
Normal domestic TV and Radio Aerials - these do not need planning permission.
Listed Buildings - You will need listed building consent if the building is listed.
Conservation Areas - You will need planning permission if the building is in a conservation area.
Repairs or Maintenance - these do not need planning permission.
Minor Improvements - these do not need planning permission eg. painting your house or replacing windows.
Internal Alterations - these do not need planning permission.
Insertion of Windows and Skylights - these do not need planning permission unless it is a dormer window or you wish to create a new bay window, which is treated as an extension.
Cladding - You will need planning permission before cladding the outside of a building with stone, artificial stone, wood or plastic etc.
Listed Buildings - You will need listed building consent in all instances if the building is listed.
Conservation Areas - You will need planning permission in all instances if the building is in a conservation area.
* please note - if you demolish a building, even one that has had fire damage, you will not automatically get planning permission to re-build it.
Size - You will not need planning permission to demolish a building such as a garage or shed if it is less than 50 cubic metres.
Health and Safety - You will not need planning permission to demolish a building if there are urgent health and safety reasons.
Other Legislation - You will not need planning permission to demolish a building required under other legislation.
Redevelopment - You will not need planning permission to demolish a building on land where there is planning permission for redevelopment.
Enclosures - You will not need planning permission to demolish a gate, fence, wall or other means of enclosure.
Listed Buildings - You will need listed building consent in all instances if the building is listed.
Conservation Areas - You will need planning permission in all instances if the building is in a conservation area.
Snowdonia National Park Authority, National Park Offices, Penrhyndeudraeth, Gwynedd LL519DX
Telephone: 01766772274 e-mail: parc@snowdonia-npa.gov.uk www.snowdonia-npa.gov.uk