What kind of certification is sufficient for a conservatory improvement?

Ena123

grumpy_codger said:

A conservatory can (almost?) never can qualify as a living space. That's why it must be separated from a living space by an external grade door.
That's why IMHO it makes little sense to certify minor improvements like in your case. The only way to make a conservatory a proper living space is to replace it with a proper extension (insulated floor,  insulated cavity walls, insulated roof, callculated allowed glazing %.
I'll be happy to be proven wrong by some expert.

The external walls on the conservatory are double wall with insulation in between. All windows and doors are double glazed. The roof is insulated, warm roof, the foam sandwich. The floor is probably of the same character (below the flooring, which it shares with kitchen as one unit) the same as under the kitchen. Does kitchen not count as living space? 
Not sure about calculated allowed glazing - does that mean the number of windows? It has one solid wall with a standard window on one side and then above the brick level to about one meter high (insulated cavity wall), it is all windows and doors up until it meets the other external wall of the rest of the building. 

Or to put it this way: the kitchen floor expands unseparated into the conservatory in like L shape. It appears as one unit. I would need to dig into the papers from sale to see whether it had a proper approval before, which I believe it did, because we paid an independent surveyor before purchase. 

silvercar

Round here, people get building sign off with external doors in place. Wait until the certificate is issued and then remove the doors and tidy up. Even if there is a load of insulation in the walls and a decent roof, it seems this is the easiest way of getting sign off.

grumpy_codger

Ena123 said:

grumpy_codger said:

A conservatory can (almost?) never can qualify as a living space. That's why it must be separated from a living space by an external grade door.
That's why IMHO it makes little sense to certify minor improvements like in your case. The only way to make a conservatory a proper living space is to replace it with a proper extension (insulated floor,  insulated cavity walls, insulated roof, callculated allowed glazing %.
I'll be happy to be proven wrong by some expert.

The external walls on the conservatory are double wall with insulation in between. All windows and doors are double glazed. The roof is insulated, warm roof, the foam sandwich. 

OK....

A traditional pitched roof with level ceiling should be insulated to achieve a U value not exceeding 0.15W/m2K. This can generally be achieved by providing a total of 250-300mm (depending on the manufacturer) quilt type insulation in two layers, the first laid between the ceiling joists and the second laid at right angles over the joists.

The U-value requirements for UK roofs are 0.11 W/m²K for new builds, 0.16 W/m²K for retrofits, and 0.18 W/m²K for flat roofs.

The lower U value, the better. Ask your company what U value of your new roof is .

The floor is probably of the same character (below the flooring, which it shares with kitchen as one unit) the same as under the kitchen. 

The same level means nothing. It can be concrete slab without any insulation.

Floor insulation for a domestic extension

in England needs to achieve a U-value of 0.22 W/m²K or lower. This can be achieved with a minimum thickness of 100mm of rigid foam insulation or 150mm of EPS polystyrene,

Does kitchen not count as living space? 

Most likely yours does. If it's an old house it doesn't have to meet the current standards, but any extension does have to meet the current standards at the time of building.

A summer kitchen in a shed doesn't count.

Not sure about calculated allowed glazing - does that mean the number of windows? 

This means the total area of the windows and glass doors. AFAIK, the calculation is about the total heat loss of an extension, so the glazed area can be higher, say, for good triple glazed windows or better insulated walls, roof and floor.

Or to put it this way: the kitchen floor expands unseparated into the conservatory in like L shape. It appears as one unit. I would need to dig into the papers from sale to see whether it had a proper approval before, which I believe it did, because we paid an independent surveyor before purchase. 

It would be nice if it was approved when it was built. However this doesn't mean that after improvements it will meat the current heat loss standards.

TELLIT01

WIAWSNB said:

TELLIT01 said:

When the roof of our conservatory was replaced with a 'Warm Roof' we had visits from Building Control and certification on completion.  That was arranged by the people doing the work.  I can't imagine they would have gone to the trouble and expense if it wasn't required.  We didn't remove the doors between the main house and the conservatory.

Blimey. Who told them?!

Why are they concerned about an outbuilding that isn't a habitable space? Could you legitimately remove the ext doors now if you wanted to? 

Yes we could. Who told the Building Control?  The people doing the work.  As I said, the contractors wouldn't have called in BC if they didn't have to.  The new roof meant that the old conservatory did now qualify as a habitable room and is.

TELLIT01

If it's relevant to the discussion.  The original conservatory has  full height walls on 3 sides with dwarf walls on the 4th to a height of about 30 inches.  It also had an insulated floor with underfloor heating.  That room now retains heat only marginally less that the rest of the house.

plumb1_2

silvercar said:

Round here, people get building sign off with external doors in place. Wait until the certificate is issued and then remove the doors and tidy up. Even if there is a load of insulation in the walls and a decent roof, it seems this is the easiest way of getting sign off.

That’s most probably what’s happened in this case, they removed the original back door after it’s been signed off.
id be tempted to refit the back door with a new frame and fire door, this will also stop heat loss from the house.
Is the new Upvc door in the conservatory your rear exit? I’d put a thumb turn lock in there as a means of quick escape.

ComicGeek

'Conservatories' have always been exempt from Bldg Regs (and still are) where they are separated from the main house by an external grade door, and are less than 30 sq.m. Pre 2006, they had to have at least 50% of external walls as glazing and at least 75% of roof as glazing/translucent to qualify - this definition was taken out of the Bldg Regs from 2010, which allowed companies to start selling retrofit solutions for conservatory roofs. Up to 2010, the installation of a solid roof would have voided the classification of the space as a 'conservatory', and would have required Bldg Regs certification for the works.

If the 'conservatory' isn't separated from the main house by an external grade door, then it isn't a conservatory - it's an extension, and should have had Bldg Regs certification when the door was removed. 

Now that it's all open plan, any works to the building fabric of the extension would need to meet Bldg Regs. As soon as you start making improvements there are minimum requirements for 'renovated elements'. Under the current English regs, that would be an improved U-value of 0.16 W/m2.K.

I've had similar projects where the Building Control Officer has required the previous 'opening up' works to be demonstrated as compliant before they would issue a regularisation certificate for the roof insulation works. Then you are into area weighted average U-value calculations and SAP offsetting calculations to demonstrate compliance. 

Ena123

silvercar said:

Round here, people get building sign off with external doors in place. Wait until the certificate is issued and then remove the doors and tidy up. Even if there is a load of insulation in the walls and a decent roof, it seems this is the easiest way of getting sign off.

Sorry, what does this mean? Why removing any door? That would open the house to the elements through the conservatory. There is the external door on the conservatory, it has been since before we bought it. 
Or are you saying to put additional door between kitchen and conservatory for sign off? I am not quite clear what this is about. 
Nobody wants to sign off anything (company speaking). They want to give me a certificate of the certification company for the roof installation company that this roof meets certain criteria. They try to avoid signing off anything at all, claiming it was like for like. 

Ena123

ComicGeek said:

If the 'conservatory' isn't separated from the main house by an external grade door, then it isn't a conservatory - it's an extension, and should have had Bldg Regs certification when the door was removed. 

Now that it's all open plan, any works to the building fabric of the extension would need to meet Bldg Regs. As soon as you start making improvements there are minimum requirements for 'renovated elements'. Under the current English regs, that would be an improved U-value of 0.16 W/m2.K.

I've had similar projects where the Building Control Officer has required the previous 'opening up' works to be demonstrated as compliant before they would issue a regularisation certificate for the roof insulation works. Then you are into area weighted average U-value calculations and SAP offsetting calculations to demonstrate compliance. 

THIS ^ seems to be our case. I'll need to look up the paperwork then. Sigh... 
Thanks. 

silvercar

Ena123 said:

silvercar said:

Round here, people get building sign off with external doors in place. Wait until the certificate is issued and then remove the doors and tidy up. Even if there is a load of insulation in the walls and a decent roof, it seems this is the easiest way of getting sign off.

Sorry, what does this mean? Why removing any door? That would open the house to the elements through the conservatory. There is the external door on the conservatory, it has been since before we bought it. 
Or are you saying to put additional door between kitchen and conservatory for sign off? I am not quite clear what this is about. 
Nobody wants to sign off anything (company speaking). They want to give me a certificate of the certification company for the roof installation company that this roof meets certain criteria. They try to avoid signing off anything at all, claiming it was like for like. 

Your original post talked of worrying when selling. If you put an external type door between the kitchen and conservatory, you comply with all the regulations you need. Then you don’t need a certificate for the conservatory as it isn’t considered part of the house.