Building a Conservatory Under Permitted Development Rights

Planning Consultant - Chris Scott
Hi, I’m Chris,
I hold an MA in Planning and work as a Planning Consultant

If you have been browsing other websites you are probably aware that in many circumstances you can construct a conservatory on your property under permitted development rights. This means you would not require planning permission, but there are various conditions that the conservatory needs to meet:

  • No more than 50% of the land within the domestic curtilage can be developed. This will include existing outbuildings.
  • The conservatory must not extend past the principal elevation of the property which faces the highway.
  • Under the Larger Home Extension PD rights, the conservatory can extend beyond the rear wall of the original detached dwelling by up to 8m, and up to 6m for a semi-detached dwelling.
  • The height of the conservatory must be a maximum of 4m for a pitched roof, and 3m for a mono-pitched roof. If within 2m of the property boundary the maximum eaves height must be 2.5m.

Now, this is all pretty standard information available through the Planning Portal. However, with this blog, I want to look at scenarios where you may come unstuck following these ‘simple rules’ without a proper review of your properties planning history. Furthermore, without going down the route of applying for a Lawful Development Certificate.

Before you order your conservatory you need to be confident it does come under permitted development – Image: Everest

Have the properties Permitted Development Rights been Removed?

If you review the rules around permitted development you may feel pretty confident your rear extension conservatory plans are within the rules. However, there is a scenario that many people are not aware of. Your property may not be able to benefit from the permitted development rights.

There are two possible reasons. First, on the approval of a previous extension the local authority removed the permitted development rights via condition. Alternatively, your property may be located in an area covered under an Article 4 direction. The Article 4 direction may have removed all or some of the properties permitted development rights.

I have a Previous Extension, can I Link my Conservatory to it?

No, under permitted development rules you cannot build an extension and link it to a previous extension. Extensions including conservatories must be built and measured from the original wall of the dwelling. This is a good example of where it’s important to review the planning history of a property. There are cases where individuals have not realised the property has been previously extended and constructed a new conservatory. Only to have a visit from the local planning enforcement officer telling them the development does not come under PD, as it is linked to a previous extension.

Claiming ignorance is not an acceptable defence when it comes to planning enforcement matters. Therefore you want to make sure with a planning history review and Lawful Development Certificate you avoid future planning enforcement issues.

Do I need Planning Permission for a Conservatory with a Tiled Roof?

It’s still possible to comply with PD rules and construct a conservatory with a tiled roof. You still need the structure to have a maximum height of 4m. Therefore if its a conversion from a conventional conservatory roof to a tiled roof the height needs to be monitored.

Also with conversions or retrofits, you need to be aware of weight. Under permitted development rules, extensions should use material similar in appearance to the host dwelling. However, the roof titles used on the roof of the main dwelling may be too heavy for a conservatory conversion. Many of the conversions are done with special low weight tiles. Therefore you need to find a title that is similar in appearance to that of the main dwelling. Again, as previously mentioned. Securing a Lawful Development Certificate for the works is not a bad idea to avoid future planning issues.

Planning History Review before a Lawful Development Certificate

In many cases, I think it’s a good idea to apply for a Lawful Development Certificate before you construct a conservatory. This will get a formal response from your local authority to confirm if they accept the proposed conservatory as lawful, and exempt from enforcement action. As stated above the local authority will determine if they believe there have been previous extensions etc which the conservatory would be linked to. However, without your own planning history review, you will have no counter-evidence to the council’s claims.

For instance, the local authority may claim that the property has been previously extended, but is there sufficient evidence to justify this claim? In some cases, there is a previous planning application as evidence. However without such evidence and using old OS maps it may be possible to reasonably conclude that the claimed previous extensions existed before the 1st of July 1948. If that’s the case in planning terms the extensions should be regarded as part of the original dwelling.

I own a Listed Building, can I add a Conservatory without Planning Permission?

It may be possible to add a conservatory to your Listed Building without planning permission, following permitted development rules. However, you will need to submit a Listed Building Consent application in all cases. As part of the Listed Building Consent application, you will need to demonstrate that your proposed conservatory would not have a detrimental impact on the character of the Listed Building. Therefore, proposing a uPVC conservatory will almost certainly result in a refusal of Listed Building Consent (LBC).

Listed Building Conservatory
For a conservatory on a Listed Building, you need to demonstrate the structure would not have a detrimental effect on the historic character of the building – Image: Everest

To secure approval of LBC requires favourable feedback from the local conservation officer. Some local conservation officers will be looking for the design of the conservatory to be in keeping. This could include the use of timber fenestration and a heritage colour palette etc. However, in other cases, they may be looking for any proposed conservatory to be obviously modern. They may prefer it to be instantly obvious where the old meets the new. However, in either case, your proposals must not detract from the heritage value of the Listed Building.

I live in a Conservation Area, how does that affect my Conservatory plans and Planning Permission?

As referenced above, if your property is based in a Conservation Area, it’s likely your permitted development rights may have been removed by an Article 4 Direction. However, it’s always important to check what the particular Article 4 Direction actually states. Where some are a sweeping removal of all permitted development rights, others are more specific. However, when it comes to extensions such as a conservatory, it’s likely those permitted development rights have been removed. Therefore a planning application would be required. Most conservation areas have character appraisal reports, these need to be reviewed to direct the design of the conservatory proposal.

Assistance to Secure Planning Permission for a Conservatory

So as you can gather from the above, a ‘simple’ conservatory extension can sometimes throw up several planning challenges. If you send me your details through the contact form we can discuss your conservatory ideas and whether planning permission is likely to be required. 🙂