Two storey side extension and existing non-compliant loft conversion

[Timmer]

Hello Forum- first post so please go easy! Hoping for some advice....

As part of our extension - the building control officer has noted that the pre-existing loft room (in a separate area to the area we are building) has not had a previous building regs approval (it was probably done c. 25 year ago by the look of the glazing and woodwork around it.)

This existing loft will have a doorway into the 'new' area, and whilst we will be replacing the internal external insulation , we were otherwise leaving it relatively untouched.

The BCO has said in order to sign off on the extension, the insulation will require upgrading in the old loft room and the floor (which would involve up-speccing the floor joists)

- he is saying that he'll not sign off the completion certificate until the insulation is fully upgraded in the old loft (both the room, and the remaining unfilled loft) - which would obviously trigger the need for a shed load of work on the ‘existing’ loft, which we’d not intended to touch...

We will not be using this previously fitted out loft room as anything other than storage - as we have a couple of new, full hieight rooms in the ‘new’ bit...

He's also said in our meeting yesterday that 'the worst the can happen is nothing' - i.e. there are no longer local authority enforcements...

I begged to differ, as my understanding that unless the completion certificate is issued - there are elements of the buildings insurance that are not covered...

He’s not been hugely helpful in giving advice, just refers to the L1b regs

Just to further complicate matters - we’ve had the existing roof re-tiled to match the new area - will add some pics to add context - but any advice most welcome - my preference would be to ‘leave it as is’ - but I understand that reverting it to ‘storage’ from ‘illegal loft room’ may involve removing heating, plug sockets & restricing access from the main house (I.e it can’t have a ‘normal’ door - otherwise it’s trying to be a habitable room....

Or should I just not worry about the sign off of it? (Given it was non-compliant before)

Sorry for the rambling post - but this (in conjunction with the other bumps in the road on out project) has been doing my head in!

Timmer

 

[Timmer]

Extension on the left - existing loft room above the front door

 

[tony1851]

Your BCO is correct.
The fact that there is a linking door between the new loft part and the existing (old) conversion is irrelevant.
It is the fact that you have re-covered the whole roof which makes the difference. When recovering a roof with new slates or tiles, you are supposed to take the opportunity to increase the level of insulation.
The fact that you haven't done that doesn't mean that enforcement action will be taken - it just means you won't get the certificate, which as you appreciate may invalidate the insurance.
Bite the bullet. You don't have to insulate to modern standards, but just try and agree a lesser standard with him.

 

[^woody^]

It is the fact that you have re-covered the whole roof which makes the difference. When recovering a roof with new slates or tiles, you are supposed to take the opportunity to increase the level of insulation.

Not quite.

The requirement is to "consider" upgrading insulation and whether it is feasible, practical, and the costs of upgrading over the playback period are less than the costs of energy it will save.

OP, you need whoever is designing this to refer to the requirements of Part L1b and upgrading of thermal elements. And they should actually read the requirements, as the BCO is wrong.

 

[tony1851]

I seem to recall we've been here before?

In para. 5.8, it states:

"Where a thermal element is subject to a renovation.........the performance of the whole element should be improved to achieve or better the relevant U-value set out in .......etc etc"

I think the operative word here is 'should'.

Ok, agree if it's not feasible then it needn't be done but the inspector is not going to accept the OP saying "I've considered it and it's not feasible". He's going to want figures or other justification as to why not.

@op; has it occurred to the inspector that you have re-tiled the roof? If not, he is incorrect in asking you to increase the insulation. Instead of him just quoting L1b, ask him precisely what part of that document he is referring to, and then call back here.

 

[^woody^]

I seem to recall we've been here

Yes this is deja vu.

"Should" is not a duty, like "must" is.

If you read the requirement it does say that insulation improvements should be considered, yes considered.

Further, the consideration is in context of the 15 year payback period.

The consideration is not a flippant "I've thought about it". It's a proper look at the practicalities and costs, and then a justification as to why it should not be done which in turn meets the requirement of L1b.

 

[Timmer]

OK - two and a half years down the line - though i'd resurrect to give a view on what has happened to us on this.

We have had the previous loft bit done (floor joists built up, rafters battened out 150mm celotex etc.) which has given a signed off (hurrah) previously functional loft room.

We now have a loft store space accessed by a door from the newly re-converted loft room.

it has a fire escape velux and the floor is proper (as opposed to the thinner joists on the other side)

We have no intention of using is as a bedroom - but i would like to use it as a chill out space.

Can i put 100mm celotex in the rafters and just crack on with OSB board?

Is this going to cause issues with the difference between an habitable and non-habitable space?

apologies if these are dumb questions - but having been burned first time round - i'm keen to get this bit right!

here are a couple of visuals form the newly converted bit into the loft storage space & vice versa

and a view of the front, so the context of the old loftspace makes sense

Cheers y'all!

Timmer

 

[kingandy2nd]

2 years and you still haven’t thanked the folks that help you first time around

 

[Timmer]

2 years and you still haven’t thanked the folks that help you first time around

rectified

as i said - new to the forum

 

[Timmer]

well, was back then