New conservatory roof guide available

Conservatory roof Building Regulations guide

A newly re-issued guide clarifies how you should go about replacing a translucent conservatory roof with any solid roof systems that have LABC Registered Details certification (now known as LABC Assured as of March 2019) and outlines the conditions you’re expected to meet to ensure the structure complies with the Building Regulations.

Whilst 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; inadequate window/door supports to take the loads.

What Building Control will look at:

  • Building Control will inspect the existing conservatory to ensure it can take the additional load of the new roof. If there are no signs of distress then it’s unlikely the new roof will cause a failure of the structure to the conservatory. This should already have been assessed by the surveyor of the company before carrying out any work.
  • We will also check that the existing door supports contain steel inserts to distribute the roof load down to the floor slab. Again, this should already have been assessed by the surveyor of the company before carrying out any work.
  • Signs of distress may mean that the existing foundations aren’t sufficient to carry the additional loads and so additional requirements are likely to be imposed on you.
  • Your LABC surveyor will also want to ensure that the new roof and supporting structure fully complies with the Regs and the remainder of the extension should be no worse than before.

Get more information by downloading your free copy of LABC’s re-issued Building Regulations


Also see: How to get your conservatory right


Please Note: Every care was taken to ensure the information was correct at the time of publication. Any written guidance provided does not replace the user’s professional judgement. It is the responsibility of the dutyholder or person carrying out the work to ensure compliance with relevant building regulations or applicable technical standards.


B4 - External Fire Spread

Submitted 5 years ago

So, a conservatory doesn't have a limit on glazing on a boundary, an extension does. This guide doesn't detail anything in relation to blocking up of windows on a boundary where they wouldn't comply with B4. Now the government take fire safety pretty seriously, see; for instance where it was determined that glazing 250mm from the boundary needs both integrity and insulation to stop fire spread, why are the installers of these roofs not being made to comply with B4??? Doesn’t this just circumvent the fire spread regulations?

Insulate part of conservatory roof

Submitted 3 years 4 months ago

Do I need Building Reg approval to only insulation the inside and leave the polycarbonate sheet on the outside?

Thanks Mary

(Dim testun)

Submitted 3 years 4 months ago

Hello there - thanks for getting in touch.

Yes you will require building regulations approval as the alteration no longer benefits from the exemption previously in place. You will also require a structural appraisal of your existing roof system (if it is not being replaced) to ensure that the profiles used for this lightweight structure are able to sustain additional loading of the insulation etc.

Kind regards
David, LABC

Comfortable Conservatories

Submitted 2 years 1 month ago


We had got quote from a Solid roof conversion for Conservatories by a company and they said they use approved low weight tiled roof system and that our conservatory (Lean To Polycarbonate roof) is less than 30 Sq Meters and separated from main house via doors that we would exempt from Building Regs?


LABC response

Submitted 2 years ago

Thank you for your enquiry, LABC has offered a view and guidance on this situation in the guidance document referenced above; however, application will depend on the particular circumstances in each case, and we recommend that contact is made with the Building Control team at your Local Authority to discuss the detail of your proposed works.

You can find the contact details of the relevant Building Control team by entering your postcode in the search box at the top right-hand side of our website.

LABC team

Removal of doors

Submitted 2 months 1 week ago

If I install a LABC compliant lightweight insulated roof to an existing conservatory and effectively make it an extension would this then mean I could removing the separating pvc doors to make it open plan to the kitchen?

LABC Response

Submitted 1 month 1 week ago


Thank you for your enquiry.

Approved document L (2021 edition) in England, considers that a compliant insulted roof to a previously existing exempt conservatory is building work by way of regulation 4 (1) and 4(3). If you then want to open that conservatory to make the space habitable then that is a change in energy status and use, and this would require an application to your LABC team where you live and will need to follow the guidance in paragraphs 10.7 to 10.11 in Part L.


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