The Celsius Solid Roof system is fully approved and registered by the LABC (Local Authority Building Control) and has also been submitted for approval by the LABSS (Local Authority Building Standards Scotland).

Click here to view Celsius Solid Roof's approval on the LABC Web Site

The LABC is a not-for-profit membership organisation that represents all local authority building control teams in England and Wales aiming to ensure that all buildings are habitable, safe, dry and warm.
With over 3,000 professional surveyors and building technicians working in local authority building control, the LABC provides a consistent national service that's delivered locally.
The definition of a conservatory and whether a retro-fit or new build solid roof solution is exempt from the Building Regulations application and approvals process is seen by many as a 'grey area'. At Synseal, we are keen to offer clarification and guidance to support the introduction of our Celsius Solid Roof.

On the 29th July 2013 the DCLG (Department of Communities and Local Government) released a circular letter, (this can be downloaded below) stating that: “To benefit from exemption, a conservatory or porch
  • must have a significant proportion of the roof and walls glazed
  • must be at ground level
  • must not exceed 30m2
  • must comply with relevant sections of Part K
  • must be thermally separated from the dwelling
  • the building’s heating system must not be extended into the conservatory or porch.”

The view of the LABC (Local Authority Building Control) operating in England and Wales is as follows:
“When work is carried out that significantly reduces the proportion of glazing, or level of translucence to the roof, the conservatory or porch can no longer be considered exempt.”

In May 2011 the LABC published a Best Practice note on application of Part L to Conservatories attached to existing dwellings, which stated: “To establish whether the conservatory extension is mainly exempt, we must look to Class 7 of Schedule 2 to the Building Regulations 2010. This tells us that in order to be exempt it must:
  • be at ground level
  • not exceed 30m2 floor area
  • be thermally separated from the building it is attached to
  • have an independent heating system from the main building
  • have glazing meeting Part N in critical zones"
There is no indication as to the amount of glazing that should exist for the structure to be considered as a conservatory. 
In the interest of national consistency of interpretation, the guidance on levels of glazing contained in the superseded Approved Document L1B 2006 still gives a valid basis for a decision. In other words an “exempt conservatory” should:
  • have at least 50% of external wall area formed from translucent materials (not including walls within 1 metre of boundary)
  • have at least 75% of roof area formed from translucent materials
  • be at ground level
  • be effectively thermally separated from the main part of the dwelling.”

When assessing a Building Regulations application for a solid roof retro-fit project, at the site inspection the LABC “would like to find”:

  • The existing roof will either be glazed or polycarbonate and usually have PVC-U windows and doors
  • The existing vertical frames will have been designed to carry the roof load
  • Assess the suitability of the supporting frames (it may be necessary to verify the type and extent of reinforcement by either drilling pilot holes or testing with a magnet)
  • If there is no reinforcement, new window frames may be necessary or additional support legs abutting to the existing frames
  • The existing foundations should have trial holes excavated to ensure they are adequate to support the new loadings.


In summary, construction of a completely new structure or replacement of an existing conservatory roof with a solid roof will involve a statutory obligation to submit a Building Regulations application.


For More information on LABC Guidelines please download the documents below. Synseal's LABC page can be found by clicking here.