Potential Pitfalls of Changing Your Conservatory to a Solid Roof, PLUS Ensuring Any New/Replacement Living Space Orangery Complies with Planning Law and the Building Regulations

When it comes to adding on a conservatory or orangery or changing a glass roof for a solid one, sadly many UK property owners have been ill advised by misinformed neighbours, double glazing suppliers and double glazing salesmen after a quick sale without advising you of the potential serious consequences.

Unfortunately senarios like this do occur and have led to expensive and time consuming retrospective planning applications (with no guarantee of success) and/or Building Regulations applications having to be made, and in many instances planning enforcement notices then having being issued to take down illegally erected structures, where neither the property owner or double glazing installer had sought the necessary legal approvals before extending or altering the current home. Usually there if often no problem having the conservatory, or orangery or extension of your dreams, as long as you first seek and obtain the necessary permissions prior to commencing work.

Some new living spaces do need both planning permission and Building Regulatory Approval, whilst some need full planning permission only, or to apply for and comply with only the Building Regulations. When it comes to replacing a translucent conservatory roof with a solid roof, most home owners with existing conservatories don’t realise that they can only do so by first obtaining Building Regulatory Approval, as by changing their polycarbonate or glass roof to a solid insulated one, the classification of the structure changes from a temporary structure to a permanent one, and in many cases will also now need planning permission due to the “change of use”.

If the existing double glazed conservatory with a translucent roof was built with planning approval, it is a legal requirement that 1) a new planning application will be needed due to “change of use” (please note there is no certainty of approval) and 2) a full Building Regulations application will also be required.

It may be helpful to know what the “official” definition of a conservatory or glass extension is. Conservatories, porches and other such glass extensions share a common description with Regulation 9(1), 21(4) stating to meet the exemption status in Schedule 2 Class 7 of the Building Regulations.

• They must be at ground level and be less than 30 square metres (over-hanging eaves or gutters count as part of the structure)

• They must be thermally separated from the dwelling by walls, windows or doors which meet the energy efficiency requirements (or retain the existing doors)

• The dwelling’s heating system must not be extended into the conservatory, orangery or porch. Heating should either be completely independent of the dwelling or be provided with effective controls to operate and isolate the heating from the dwelling

A double glazed conservatory or any other type of glass extension must have a significant proportion of the roof (75%) and walls (50%) glazed or translucent to be exempt from having to apply and comply with the England and Wales Building Regulations. Consequently by adding a solid rood the structure then becomes a full blown actual extension with all that entails regulations wise.

The local Building Control Officer may require the new structure to have roof vents, and/or trickle vents retrospectively fitted to windows, or other changes made to the existing structure, such as underpinning the existing base if it is not sufficiently deep enough. There will certainly need to be adequate ventilation in order for the structure to comply. Even if the new solid roof system itself has building regulation approval as a product, the remainder of the structure may also need to be altered comply. In some cases property owners may unwittingly be exceeding any intact Permitted Development Rights if the floor area of the conservatory is greater than PD rights allow. If since the conservatory was built the Permitted Development Rights on the property have been withdrawn by the local authority, then it will not be possible to add a solid roof without first obtaining planning permission.

In most cases the existing roof will either be double glazed or polycarbonate and will have PVCU windows and doors. If the roof is double glazed, the vertical frames should have been designed to carry the glass roof load. This will not be the case with a polycarbonate roof, where the vertical frames may only have sufficient reinforcement to carry that particular load and the foundations of the base may not be deep enough. When there is insufficient reinforcement (which is usually the case) new window and door frames will be needed to support the weight of the new insulated solid roof. Sadly several “new” replacement solid roofs have already collapsed due to insufficient load bearing, poor design and lack of structural calculations undertaken by installers.

Almost all pre 2010 aluminium and PVCU conservatories are not likely to have A energy rated windows and doors, so without changing any existing non-thermally broken window and door products to one’s that have a thermall break and a decent A or B Window Energy Rating, UK home owners are “wasting” their money changing to a solid roof without also changing the windows and doors, as otherwise the cold is going to come in and the heat is going to go out through the old inefficient windows and doors.

The Local Authorities Building Control guidance on adding a solid roof structure states “your local authority building control team is likely to ensure that the roof and supporting structure fully complies with the Building Regulations.” So before ordering a solid roof for an existing conservatory or a new structure that has a solid roof, do please make sure the necessary planning permission and Building Regulatory Approval is obtained before money changes hands and work starts.

For free expert design advice and a free consultation from independent suppliers and installers Hazlemere Window Company, visit hazlemere.co.uk and request an appointment with one of their  experienced expert conservatory design consultants.