Existing single skin extension - Upgrade or rebuild?

[mebedforduk]

Morning all

First post so here goes

1800 Cottage in the sticks. Its been added to over the years including a Timber frame section we have build over the last 5 years.

On the rear is a 2.70 by 2.40 single skin pitched roof 1960s addition. It was battened, quilt insulated and P boarded on the inside when build so was pretty good in its day. Pantiled to match the main house and render to match also.

It is bloody cold though!

So Plan A
Knock down and rebuild - We have trees and public sewer nearby plus clay so it will be 3.00m Founds again so would rather not
So Planning we should be Ok with as its side elevation and within permitted sizes
Full Building Regs

Plan B
Replace quilt insulation with 50mm Celotex, VP on outside face, batten with 50mm Celotex and then clad with Hardiplank etc.
Replace probably all roof timbers insulate loft, breathable felt and retile with existing.
Gun up floor and relay with a DPM and insulation
No Planning, B Regs - Hmm grey area as its existing

Plan C
Take down single skins and rebuild as Timber frame. Roof as well
Full B regs which will then mean new footings - or will it? if I leave plinth of brickwork to build from

Plan D
Put up with it

Thanks all

Cheers

Mark

 

[Deluks]

Each of your options has its own price tag. If cold is the only problem with it then seems madness to demo it, when insulation can be added internally. Is is heated? Double glazed?

 

[mebedforduk]

Hi

Yes it is heated via a rad but its like heating a open shed at the moment.

It has a new UPVC window and a very cheap and nasty ill fitting UPVC patio door set probably about 20 yeas old.

Its my office so its used all day every day. At the moment Ive lined the ceiling and walls with 25mm Celotex as a temporary and its made a huge difference ie gone from 5 Deg C in the mornings to 14 Deg

So I think Plan B will be the way forward

Cheers

 

[SittingBull]

I'd go with plan B. It would appear to be the most cost efficient way of achieving your desired result. It seems pointless to demo the whole thing with all that expense to create a relatively small room.

Good luck with whichever option your go for!

 

[mebedforduk]

Well as with all work its growing
Started to remove a section of bad brickwork to install a new window with a timber frame panel below and adjacent. Also remove roof and renew timbers giving me a chance to insulate to the gills.

Anyway, the remaining walls are now in a big heap. - Over zealous mate labourer.

I cant now work out how it sits with B Regs

If I rebuild all walls in single skin brick I am back where I was but as far as I can see, then insulate inside etc

Or build up in Timber frame as per new regs even if I don't tell BCO.

Don't really want to alert Mr BCO as he will want 3.00m deep footings

Im assuming there are some footings in place