Conservatory Building Regulations - are they not fully exempt?

Yes, but with conditions and requirements attached. Conservatories and the Building Regulations have always trod a delicate path for years ever since they were made as an exempt category under pressure from the conservatory trade itself.

When conservatories did come under the control of the Building regulations, most conservatory designs were hard to prove that they actually stood up and it became a nightmare trying to prove them structurally unless you were a large manufacturer. So it came to pass that provided certain requirements were met as part of the installation and material process then they would not need to be under the control of the council and receive their approval.

The three main requirements that a conservatory house extension must adhere to in order for it to be exempt under Building Regulations are these:-

1 - The glazing used must comply to the current version of the Building Regulations relating to health and safety rather than thermal performance. Therefore whatever would be applicable for a true house extension under glazing regulations must also comply to the conservatory extension.

2 - The conservatory must be separated from the main living environment of the dwelling house. Therefore, they must not be opened up integrally into the home, The doors and windows separating the conservatory from the rest of the house must also be thermally efficient as for external use. Providing single glazed internal doors or glazed panels with no draft stripping etc. would not make the conservatory exempt.

3 - The conservatory must not be heated other than for possible background heating to prevent freezing not exceeding a certain wattage per square metre of floor area as stated within the Building Regulations.

However, many conservatories do break these rules as many are opened up into the main home post construction. This can become a problem when the property is later sold and a clever surveyor or solicitor spots this anomaly.