Building regulations and planning permissions for conservatories
It may be a surprise to learn that the decision to extend your house is not entirely yours. Often you’ll need to get planning approval, and failing to run these checks could prove costly.
Getting retrospective planning permission is an offence. At best, you may have to make expensive amendments at your own expense. Local authorities even have the power to tear down illegally built structures. We strongly recommend that you get the go-ahead before you build – any good conservatory company will be able to help you arrange planning permission.
Planning permission is required by UK law in order to allow you to build on, or change, the use of land or buildings. Conservatories can be an exception to this rule, as like other glazing they count as a ‘permitted development right’. Single-storey extensions can be built without seeking permission first, as long as they abide by these conditions:
- The conservatory does not cover more than half your garden
- The house has already been extended
- The roof ridge or top point is no higher than the eaves of your property’s roof
- There’s a maximum height of 4 metres, or 3 metres high if within 2 metres of boundary
- Side extensions must not extend beyond half the width of the house
In 2013, the government doubled the size of permitted conservatory developments. Now, until May 2019, you can extend outwards by up to 8 metres for detached properties, or 6 metres for other house types. Instead of applying for planning permission, you will need to undergo a ‘Neighbour Consultation Scheme’. This will ensure that your conservatory doesn’t impact negatively on your neighbours’ living space.
For terraced houses, flats and maisonettes, you will still need to get planning permission.
Whether or not your conservatory will need planning permission depends entirely on your project specification, and every case is individual. A good company will assess your conservatory design and location in order to establish if planning, listed building or conservation consent is required. They will also prepare full plans and submit them to your local authority for you. Some companies will offer this for free but some may want to charge, so check that this is included in the service.
There is more information available on the government’s planning portal.
Complying with building regulations is a separate matter to planning permission. The building regulations set the standards for the health and safety of buildings and their users. The majority of conservatories in England and Wales are exempt, but there are circumstances where an application will be necessary. A conservatory is exempt from building regulations when:
- Built at ground level
- Less than 30 metres square
- Separated by an external wall, or external windows and doors
- The conservatory has an independent heating system
- No less than 1 metre away from any boundary
If you want to remove the doors or wall linking the conservatory to your house, you will have to apply for building regulations approval. To satisfy requirements, you will have to prove that your conservatory is as energy efficient as the rest of the house, and not an energy drain.
Your company will need to prepare full working drawings, including full structural and heat-loss calculations where necessary. They will then submit them for approval, notifying your local authority at all key stages of the installation.
Scottish building warrant approval
Building warrants are similar to the building regulations in England and Wales, in that they refer to the health and safety aspects of the structure, rather than the aesthetic considerations. Conservatories built in Scotland are exempt from building warrant approval when they meet certain criteria:
- Smaller than 8 metres squared
- Located at the rear of the property
- At the side of a property, not facing a road
- No less than 1 metre away from any boundary
- Does not contain a chimney or flue, or any bathroom plumbing (i.e. no showers or toilets)
If your conservatory design does not meet these requirements, you’ll need to get building warrant approval. Some replacement roofs and porches will also require permission, as will open-plan extensions.
Scottish building regulations are complex, and it's not easy to say whether a certain type of structure will get building warrant approval or not. We recommend choosing a conservatory company with a surveyor who will check and apply for the relevant permissions on your behalf.
Water board authority approval
If you're building on or within 3 metres of a public sewer, you need permission from your water board authority. After installation, your local building control officer will have to inspect your conservatory to check that no damage has been done.
Listed buildings, conservation areas & restrictive covenants
If you live in a listed building or conservation area, you’ll need to ensure your new conservatory is in-keeping with your property.
Houses in conservation areas, national parks or designated Areas of Outstanding Natural Beauty are subject to ‘Article 4 Directions’. These restrict the work that you can do to the outside of your property, without first getting planning permission.
This is also the case if your house has a restrictive covenant. This is a private agreement detailed in the title deeds of your property, which restricts the way land may be used and developed.
Conservatories and extensions to these properties are subject to permitted development guidelines. In most cases, conservatories can be added if their design is sympathetic to the property's aesthetic. This means frames and glazing must match the rest of the property, and cladding such as pebble dash is not allowed.
If this is the case, it’s often simpler to find a company who can help you apply for and gain consent for your project to get the go-ahead. Look for companies with previous experience of getting conservatories approved in conservation areas.
Party wall approval
In England and Wales, a party wall agreement may be required for the proposed conservatory. This is an agreement between two parties regarding the construction on or near a boundary separating the two properties. You must give at least 2 months’ notice in writing to your neighbour if you will be making changes, like excavating near their property to lay conservatory foundations. Your company should be able to help obtain this approval.