When does my Conservatory become a Single Storey Extension?
The rise of requests we are seeing for solid roof conversions onto existing conservatories is bringing with it some interesting stories and not all of them are true.
So in order to clear up some misinformation that is being spread around by ‘other’ home improvement companies lets delve into the facts;
In times gone by it was fairly straight-forward to determine the difference between a Conservatory and an Extension.
A Conservatory used to be clearly classified in (AD L1B 2006) as a structure that met the following criteria
- Under 30m2 in size
- At least 75% translucent roofing
- At least 50% glazing to walls
- Be at Ground level
- Be independently heated
- Have thermal separation from the main dwelling with doors of an exterior quality.
This was revised in 2010 and has now left a situation where a Conservatory is not clearly identifiable. But reference to the above can still be used to classify a Conservatory as a Conservatory and not an Extension.
There are two key differences that remain and they are; thermal separation and independent heating. There is ‘fog’ around size, roofing translucency and the amount of glazing in the side walls but the two aspects that deal with thermal performance are fairly well set.
To understand the differences a bit further let’s look at the regulations concerning the two DIFFERENT structures.
A Conservatory does not need to comply with Building Regulations. But an Extension does require Building Regulation Inspection and Certification.
A new solid roof on a Conservatory requires the roof to be LABC (Local Authority Building Control) compliant and for the foundations to be substantial enough to take the added weight of the new roof. It needs, therefore, to have an inspection of the foundations and the roof needs to be LABC approved. All too often we come across customers who have gone down the cheaper route thinking they were getting a fully compliant Conservatory conversion when in fact all they have been sold is a LABC approved roof but had no building control inspections to ensure the structure as a whole is compliant and therefore no completion certification has been issued.
A quick note on the added weight: we see a lot of companies offering ‘lightweight’ roofing solutions but take our word for it a glass roof is heavy! The building regulations are more concerned with the additional weight that can potentially sit on a roof when it snows. The problem arises because a glass roof isn’t as thermally efficient as an insulated solid roof. Any snow falling on a glass roof will slide off as the ice bond between the snow and glass can’t form. On an insulated solid roof, however, the ice can grip the roof covering and the snow can sit on the roof. As it continues to snow, the weight will build up until, at some point, it will fail. We have even come across companies claiming to convert existing polycarbonate (extremely lightweight) roofs by insulating underneath and then fitting plasterboard and finishing off, a potential disaster in waiting! The original roof would have been built to take the weight of polycarbonate sheets and little if any, snow loads. Once it becomes insulated and snow can sit on top, it is only a matter of time before failure will cause the roof to collapse.
A Conservatory without doors between the house and itself is an Extension and needs to meet the regulations for an Extension.
We are repeatedly asked to remove the thermal separation (doors between house and Conservatory) when refurbishing an existing Conservatory. This turns the Conservatory into an Extension. Not surprisingly, there are a whole different set of rules regarding building an Extension. We come across companies who say “just sign this disclaimer and we can get on with the work”. Our advice is: if you’re investing in a refurbishment of your Conservatory and want to have it opened to the rest of your home, do it right. Spend a bit more and be assured that, should you choose to sell your home, you won’t need to worry about worthless indemnity insurance policies or suffer stress when your solicitor asks you for the paperwork to go with your Extension. Interestingly, did you know that the LABC department can force you to rectify or remove an incorrectly build Extension and for the little extra it costs to do it right, it really is not worth the risk.
Some real benefits of correctly converting a Conservatory into a Single Storey Extension
When a home is valued for sale, the price suggested is worked out on habitable space. A Conservatory is deemed to be uninhabitable. An Extension, however, is a habitable space and the floor area would be taken into account. So if you correctly convert a Conservatory into an Extension you could also see the value of your home rise.
Done correctly Conservatory conversions add comfortable living space that can be used all year round. A far cry from the Conservatories of old or a conversion that has not been done correctly!
How can a Conservatory become an Extension with all that glass?
If you were building an Extension from scratch it would need to fall in-line with the regulations and would have a maximum of glazing that equals or is less than 25% of its floor area, plus any glazed area being enclosed within the new Extension. A converted Conservatory on the other hand is likely to have much more than the notional 25% and would, therefore, fail the building control test of maximum glazed area. There is a legitimate way to overcome this and prove to the building control inspector that the Extension can be ‘proved’ with more than 25% floor area to glass ratio. There is an excellent article on the Architects Journal website click here to read it, it covers the overglazing issue very well.
Take away points to consider when Refurbishing your Conservatory and turning it into a Single Storey Extension
- Always insist on Building Control Certification for the WHOLE job not just the roof.
- Make sure your roof is LABC approved.
- Make sure your foundations are good enough to meet the regulations and have been inspected/signed off by LABC.
- If removing the ‘thermal barrier’ doors ensure the correct process has been followed.
- What allowance has been made to improve the thermal performance of the existing structure?
Remember.. an incorrectly constructed, over-glazed Extension can be forcibly removed by the local council. But more to the point, an incorrectly constructed or refurbished Conservatory will be uncomfortable and in some cases potentially serious risk to health and injury.
If you want to know more about our Conservatory refurbishment service or if you are interested in finding out more about our Glazed Extensions please feel free to get in touch either by phone or simply fill out the form below and arrange an appointment to suit you.