Knock or Renovate?

dubber

We have an old 50s extension, no dpc nor insulation in the floors etc. It's single leaf block built, not sure if it's cavity block or solid. It's certainly not a total ice box, but when the temperature drops you certainly don't want to be hanging around on the tiled floor if you've no socks on. I have to do some work on it anyway, new roof and resolve some exterior drainage issues, I then got on to thinking of laying a membrane over the existing slab and a thin layer of insulation and possibly wrap the whole thing in EWI ... but if I'm going that far I may as well knock the whole thing and start over, but this involves moving out, cost of renting etc. Am I wasting my money trying to fix it up, is knocking it while more expensive now, a better use of money longer term?

Dudda

Hard to tell without seeing it but from the above description you're probably better off knocking it. TBH it would be hell living in it during the refurbishment and you'd probably end up moving out and paying rent especially if the roof is getting replaced so no saving there.

Dardania

whats the function of the space e.g. a kitchen / part of the living area? Are you happy with the layout / sunlight etc.?

dubber

It's a kitchen, layout is fine, we'll be pretty much rebuilding what's there.

Water John

On the floor, I think the choice is leaving it alone or digging it up. That is putting in full insulated floating slab with no bridge to the wall as per UFH.
I'd say if you weren't knocking the walls you could only dig inside the presses as you won't be putting heating under them anyway.
Don't have a strong view on the walls.
A lot of your decision has to do with the budget.

mcneil

you knock it, your going into massive costs to build a new house. It can fixed for a fraction of the cost of a newbuid. massive costs even before a block is laid now on new bilds

BryanF

mcneil wrote: »

you knock it, your going into massive costs to build a new house. It can fixed for a fraction of the cost of a newbuid. massive costs even before a block is laid now on new bilds

Massive?

this is a single leaf extension, no size was given and no visuals or structural report available, on what basis can anyone offer an opinion on whether it can be retained or should be knocked?

dubber

BryanF wrote: »

Massive?

this is a single leaf extension, no size was given and no visuals or structural report available, on what basis can anyone offer an opinion on whether it can be retained or should be knocked?

Total extension is about 20 sqm. There are no structural issues apparent other than cold walls/floor and moisture due to no insulation/dpm.

Water John

dubber, it really an issue of budget and what you want to achieve. If you are happy with the kitchen layout, presses etc, I would be veering towards to seeing can a reasonable job be done, leaving the walls and kitchen.

You are redoing the roof, plenty of insulation.
I think I would dig out the floor. plenty insulation again. I would consaw the floor just by the presses and dig. Plenty of insulation, again. This is the only chance to insulate the floor and do a good job here.
I have seen a digout done on old buildings, especially where they are putting in UFH. but the same structure applies.It would be easier if the kitchen units were moved but that might not be practical.
Tile the floor.
External insulation is fairly pricey and you can do later if you are stretched.

If the windows are double glazing I wouldn't replace them.

Calahonda52

dubber wrote: »

We have an old 50s extension, no dpc nor insulation in the floors etc.

what 100% proof have you of this.

is there a dpc in the walls?

are the walls built on the floor or is it done properly?

If the roof and walls are sound and built properly, then digging out 20 sq m is not a big deal, assuming no services buried in floor. u can get a small digger in through most doors

dubber

Calahonda52 wrote: »

what 100% proof have you of this.

I don't.

is there a doc in the walls?

Not that I know of.

are the walls built on the floor or is it done properly?

Not sure.

If the roof and walls are sound and built properly, then digging out 20 sq m is not a big deal, assuming no services buried in floor. u can get a small digger in through most doors

If my budget will support it, I'm going to demolish and rebuild, if not, I'll dig up the floor as suggested here.

Thanks for the opinions!

Calahonda52

if the walls have a dpc and u are getting drainage work done outside, then maybe consider properly done EWI that goes down below ground level and goes all the way up under the soffit board to meet the proper level of insulation in the attic.

Price the demolition cost and the price of rebuilding back to where u are now...

Its an extension built onto an older house so if you make the new bit a snug as a bug etc but don't manage condensation etc from kitchen, depending on the makeup of the older part, you run risk of fabric deterioration in the older part due to different building fabric performance standards.