Is building reg required

[peweuk]

A friend owns a house which has timber cladding on the outside.
They wanted to change it for UPVC cladding and had to apply for planning to do this.

The contractor now doing the job has never mentioned any need for building regs approval, but I was sure that if any work was being done on external walls which had not previously had insulation that such work needed build regs approval and the walls would require either internal or external insulation.

Is this the case, or am I confusing it with something else?

 

[^woody^]

Yes if rain screen cladding and not just decorative, and more than 50% or the elevation area.

The requirement is to "consider" insulation in context of a cost/payback period, just do it regardless.

Edit - to clarify 50% of the individual element surface area or 25% of the whole building envelope.

 

[peweuk]

Thanks @^woody^

The work is being done on a building which is in a block which was originally a holiday let and is now residential. The construction is timber frame with a plywood face onto which was pinned wood cladding - which was deteriorating needing replacement.

They decided to have it replaced with UPVC cladding and for that they had to apply for planning (???).
However it was not until the cladding was removed when they realised that there was plywood facing under the cladding, then the studwork then the interior plasterboard.

The contractor told them that it was pointless removing the plywood and insulating between the studs as he could face the plywood with 7.5mm insulation then fit the new cladding which would give them as good insulation as could be achieved by insulating between the studwork.

I am dubious about the insulation as I do not know of any material which at 7.5mm when added to plywood would give the same degree of insulation as say 50 or 75mm of celotex (or similar).

Back in 2010 when I was adding an extension to our old rendered cottage, some of the rendering needed attention and the BR officer told me that if the area which needed repair was over 1sqm the whole wall would have to be insulated to current standards and would need BR approval - so I thought that taking off the whole cladded face of a property and replacing it would require insulation to current new build standards, and have to be approved by BR.

 

[^woody^]

There is no such wonder material that will be 7.5mm thick.

 

[Nakajo]

I don't think you're going to find a useful product thinner than 20mm.

 

[wessex101]

I assume the builder is talking about one of those multifoil insulation products but sounds like he has got his wires crossed, you cant just nail it to the plywood and then fix the cladding directly on top. It is supposed to be fixed to battens with air gaps so usually ends up more like 50mm thick overall.

 

[^woody^]

I did not think that any multi-foil could be placed on the cold side of a frame anyway.

 

[wessex101]

I did not think that any multi-foil could be placed on the cold side of a frame anyway.

It was the only thing I could think of that was that thin. Although I've just remembered that foil backed bubble wrap that sprung up in the 80's, can you still get that stuff?

Stiff a crappy idea though whatever they are proposing.

 

[^woody^]

There is always the 2mm polystyrene roll that is sometimes used before wallpapering.

 

[noseall]

There is always the 2mm polystyrene roll

First layer goes horizontal and second layer goes vertical. Repeat 150 times - hey presto!

 

[^woody^]

First layer goes horizontal and second layer goes vertical. Repeat 150 times - hey presto!

Hmmmm. I'm coming to inspect some of your jobs.