Fewer conservatories & porches are now exempt from the new Building Regulations since 1st October 2010

Aluminium Lean to Conservatory Built by Hazlemere Windows
Aluminium Lean to Conservatory Extension Built by Hazlemere Windows in Ickenham, Middlesex
The Government document L1B “Conservation of fuel & power in existing dwellings” that came into effect on 1st October 2010 introduced more stringent legal regulations as to when new conservatories and porches can be exempt from having to apply for and comply with the new Building Regulations.

One important Building Regulation that the government authorities appear to have “missed out” in error in relation to building a conservatory, is that a minimum area of 50% of the combined new vertical sides must glazed, and a minimum of 75% of the roof area must be glazed, as if not the structure falls under building regulations and must apply and comply with the new Building Regulations, which means the conservatory will have to meet the new energy efficiency requirements as well as have approval from Building Control from your Local Council.

The more restrictive exemptions from building regulations mean that it is important to ensure that if you are considering improving your property by adding a conservatory or porch that you either ensure what you are planning to build is exempt from the new Building Regulations or that you apply and obtain them, then comply with them. This is on top of making sure that you have planning permission, a Certificate of Proposed Lawful Development or legal documentation showing all the development is within any permitted development rights your property may or may not have.

The two key paragraphs of document L1B relating to Conservatories and Porches and the new current Building Regulations are 3.15 and 3.16

3.15 states “Regulation 9 exempts some conservatory and porch extensions from the energy efficiency requirements. The exemption applies only for conservatories or porches:

* Which are at ground level

* Where the floor area is then than 30m2

* Where the existing walls, doors and windows in the part of the dwelling which separates the conservatory are retained, or if removed, replaced by walls, windows and doors which meet the energy efficiency requirements and

* Where the heating system of the dwelling is not extended into the conservatory or porch.”

3.16 states “Where any conservatory or porch does not meet all the requirements of 3.15 it is not exempt (from Building Regulations) and must comply with the relevant energy efficiency requirements.”

Don’t be under any illusion, the new “energy efficiency requirements” are very very demanding and don’t just apply to windows and doors or the type of double or triple glazing, but to walls, roofs, cavities, flooring, in fact virtually everything to do with any new and/or existing structure etc. Consequently, if you want to keep costs down, reduce lead times, cut red tape down and not spend a fortune on legal, professional and administrative fees, do ensure that a) your new conservatory or porch complies with all the exemption criteria set out in 3.16 above, and b) you have obtained all necessary planning consent or written permissions before building a conservatory or porch.


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