underpinning, one for building control/Hugo.

[Tim Lamb]

In message , Tim Lamb writes

Sadly the friendly Building Inspector has moved to another authority.

I did pick up a few points during a long chat with an architect....

It is possible that remedial action at one location could cause problems elsewhere; if the rest of the building is also on the move but more slowly. This could probably be identified with a couple of test pits.

Also, Insulating the floors is not going to impact hugely on thermal losses. With my usual aversion to sums, I have not actually done any calculations. He said that with only 25mm of PIR insulation in the walls (lath and plaster, 4" studwork, render, 25mm PIR, feather edge or more render) and relatively large old spacing DG windows, a carpeted solid floor is not going to be the biggest loss. I really must do the sums!

[Andy Burns]

I thought you were talking about UFH though? On top of a uninsulated slab, surely that's going to waste a lot of energy heating the soil?

[Onetap]

Some 20+ years ago I lived in a 3 storey terrace, built 1860ish. A neighbour had an extension built. Building Control inspected the existing foundations; there were none, no footings, no concrete, nowt, wall built straight off clay.

The builders had to take out the entire back wall, supporting the roof and floors on Acrow props while they rebuilt it.

The district surveyor was heard to say that the entire street should have been demolished.

No subsidence in my house, but the rear wall was bowed. If you stripped off the plaster, there were virtually no whole bricks on the inner faces of the walls, all broken bricks. I sold up and moved on.

[Adrian]

Are the houses still there?

[Tim Lamb]

Yes. I just got a bit nervous of the cost/benefit side of the project.

3 linear, roughly equal sized rooms of about 20m2 each. One suspended, one screed over polystyrene and one wood block over concrete. All carpeted, heated with wall hung radiators and *open plan*.

The benefits... no radiators, chance to lose a step between rooms, modest energy saving, opportunity to cure rising damp in one wall and possibly fix subsidence in another and?

The downside... largely cost. The carpets will have to go, floor finish in engineered wood or ceramic tiles is not cheap. Linking the underfloor system to either GSHP or the existing log burner adds complexity to the heating control system. The FITs which were going to be available for alternative heat sources do not seem attainable currently. Partial underfloor heating which suits 24 hour occupation (us currently) may not suit some future occupier.

>

[Onetap]

[Onetap]

Yes. Been there 150 years, so I'd think they've probably done all the settling and subsiding by now.