Do I need building regulations approval for my new conservatory? – Ask Anna Question of the Week

Dear Anna,

Do I need building regulations approval for my new conservatory?

Conservatories can be a fantastic addition to your home and can be more cost-effective than an extension if your budget is limited. They can provide a fantastic space to fully appreciate your garden and are usually bright and filled with extra sunlight, although they can also be very cold in winter and very overheated in summer. That’s why an exempt conservatory must retain proper doors between it and your house – they’re not designed to be an all-year-round room.

Exempt conservatories don’t require you to submit a building regulations application. However, they will need to comply with specific criteria to be classed as exempt:

• It should be a single storey structure at ground level.
• It should have an internal floor area of less than thirty square metres.
• It should be separated by a wall or doors from the main house
• It should not restrict exit from any escape windows/doors
• It should not have fixed heating like a new radiator running off your central heating system. This is because of the expected heat loss through the structure.
• It should have at least 50 percent of its external wall area glazed and a translucent roof.
• Any glazing in critical areas should be marked safety glazing.

Will your new conservatory meet all these requirements?

If the answer is no, then you will need building regulations approval!

You’ll also need building regulations approval if you’re planning to install a sink, toilet (in a cubicle!) or other plumbing.

What about open plan conservatories?

Because open plan conservatories are not separated from the main house by a door or a wall, they are considered to be an extension and so they require building regulations approval. This may be difficult to achieve without heat loss calculations because of the excessive glazed area and resulting heat loss.

More things to keep in mind about your new conservatory:

Conservatories are expensive to heat in winter and hard to stop overheating in the summer.

Have you thought about foundations? Are there drains running underneath?

How will you prevent water from getting in?

You may also require planning permission: make sure to check with your local Planning Authority before starting the work.

What about if I want to replace my conservatory roof with a solid roof?

If you intend to replace your translucent roof with a new solid roof, you'll need to submit a building regulations application as the change will need approval. (View this LABC guide on solid roofs here.)

While most existing conservatories will be able to support the increased loads, potential pitfalls include inadequate foundations that could move and cause settlement differences between the conservatory and the existing house, leading to cracks and water leakage and inadequate window/door supports to take the loads.