Building Control Inspector & Insulation

Play_fair84

Hi,

Hope someone can provide information or insight to this.

We have a 1935 house with a 60/early 70’s extension. We are renovating parts of the extension, sun room part have build on existing dwarf walls as reducing windows new French doors etc. the original walls have a 50mm cavity and obviously new brick work just continues this. Inspector saying does not meet building regs and will have to add internal stud work and 50mm insulation for sign off…

The other part of extension used to be annexe bedroom and bathroom but converting into integral garage. One wall of this is actually original wall of old/main 1935 house, which is cavity wall but no insulation but existed this way long before the extension. Inspector also saying that wall needs internal stud work and 50mm insulation!

Questions:

how can 2026 building regs apply to improvements to a 1935 house?

How were the plans passed initially by building control/council with this all on and now they are saying it won’t pass?

how can an old original wall require insulation when it has always existed in that way, but even so is now in a garage space that will be uninhabited and un heated?

what happens if you don’t comply as don’t have the budget to cover substantial amounts of further internal insulation?

Frustrated that we are facing thousands more for things that seem illogical, also not a structural/safety issue involving gas or electricity etc!

TIA

born_again

Building reg apply at the point of build (2026), & are not dependent on the age of the house (1935). Or you would be able to get away with work that is no longer compliant.

Have to wonder why you would want a renovation of a extension with out better insulation ? This is MSE 🤷‍♀️

Perhaps best taken up with who did the design & plans. As they should have known the current build regulations.

Section62

how can 2026 building regs apply to improvements to a 1935 house?

Because you are doing building work in 2026, not 1935. The regulations apply to work when it is done. If you are modifying an existing structure the regulations can require some kinds of additional work. Thermal insulation is an example where the regs can require improvements even to parts of the structure you aren't directly working on.

How were the plans passed initially by building control/council with this all on and now they are saying it won’t pass?

When were the plans passed?

how can an old original wall require insulation when it has always existed in that way, but even so is now in a garage space that will be uninhabited and un heated?

You would need insulation between the garage and the rest of the house, but are you saying the council wants thermal insulation between the garage and outside?

what happens if you don’t comply as don’t have the budget to cover substantial amounts of further internal insulation?

The council can take enforcement action. If you still don't comply this can result in the council doing the work in default (and charging you) and the possibility of a criminal record, unlimited fines, prison time. It could also make your property difficult to sell. Even if the action is at the lower end of the scale it is likely to cost you a lot more than the cost of the additional insulation.

Frustrated that we are facing thousands more for things that seem illogical, also not a structural/safety issue involving gas or electricity etc!

Building regs cover a lot more than safety. Energy (and water) efficiency have become far more important than they used to be.

Play_fair84

Thanks both, helpful and insightful comments.

I thought when the plans were submitted months ago to building control/local council, they were essentially approved or not because they (via architect) did come back on a couple of things we had to amend in the plan (but none of this insulation issue).

also do we have a grace/time period to complete I.e if we say we will do it but next month or 2 due to budget?

born_again

what happens if you don’t comply as don’t have the budget to cover substantial amounts of further internal insulation?

The council can take enforcement action. If you still don't comply this can result in the council doing the work in default (and charging you) and the possibility of a criminal record, unlimited fines, prison time. It could also make your property difficult to sell. Even if the action is at the lower end of the scale it is likely to cost you a lot more than the cost of the additional insulation.

They can also enforce that it is demolished.

EssexExile

Don't confuse planning permission with building control, they are separate things.

ComicGeek

https://forums.moneysavingexpert.com/discussion/comment/81887276#Comment_81887276

You should be asking the architect why their proposals did not meet Building Regs requirements to begin with - what the BCO is asking for is the minimum requirement, and should have been included already. I don't see any surprises there.

Potentially you could argue that the sunroom extended walls could be slimmed slightly using an offset SAP calculation, but you should be looking to install as much insulation as possible anyway. It's cheap to do at this stage, I can't believe it will be 'thousands more'. Perfect time to make savings on heating costs.

sheenas

agree with others that the architect should have specified this and should explain why they didn’t. Building control requirements are the basics i would be asking what else has been missed.

rob7475

Any new work needs to meet current building regs. I'd be a bit concerned that neither your architect or your builder didn't realise this.

New walls will need insulating, either internally, externally or within the cavity if one exists.