Digging concrete slab/floor

[league67]

Disclaimer; I know/understand nothing about buildings / footings / foundations and as such will seek advice of builder / structural eng / architect. (part of the question is who to ask).

I'd like to dig ground floor about 30-40cm in order to gain some ceiling height and install underfloor heating throughout.

Is this prohibitively expensive and can I do it at all without house falling down. As we are doing extension next year, the plan would be to do it at the same time. House is of 2003 vintage.

Thanks.

[league67]

Spudler said:

Instruct a reputable builder.
Very straight forward works.

Do you cover Daventryshire?

[league67]

Muncher said:

Yes you can, we did it last year, well worth it but bear in mind the following will be needed:

- new external doors
- new internal doors and liners
- will the windows remain at a sensible height?
- will the light switches and sockets be at the right level?
- you will need a new staircase
- all new architrave and skirting
- new foul water drainage inside if the levels no longer work

It's certainly worth doing and I would highly recommend it but it needs to be part of a major program of works.

I was thinking about all that apart from windows height and foul water drainage. I'll need to think more about that. Everything else is accounted for.

Love your build btw. With garuhun's and pvpour's (spelling?) my favourite builds.

[league67]

B17NNS said:

Might be a block and beam floor. Are there any air bricks outside around the DPC level?

I think they are. I'll take some pictures and post. Thanks.

[league67]

Spudler said:

In that case it 'should' be block n beam-insulation-screed...assuming it's not T&G on insulation.

Is there any reason you can't retain the existing finished floor level?

I want to have ceilings to be 2700-2750 instead of 2400. As per op I'm completely dense when it comes to building things, but I like my comforts. Going to take some pictures maybe it'll make more sense

[league67]

We have just moved in, so please disregard the mess.

Here we go.


IMG 1

IMG 2

IMG 3

Current floor level in red, desired floor level in green (image1). From what I've seen it looks like concrete, it could be screed, I don't know how to tell difference.

Image 2 showing different levels ( I plan to remove slabs and level garden). Also that white dumbass pipe is annoying (waste water), is it possible to hide it?

Image 3 showing (what I think is) air brick thingy. Could be wrong.

Thanks.

[league67]

Spudler said:

The UFH is always possible but in your situation reducing the floor height isn't an option.
Suspended timber floors is possible but to drop a block n beam isn't really possible.

Spudler,

Thanks very much for that, I've googled up block and beam and I can see why it's a no go. Oh well.

[league67]

Thanks very much everyone for their input.

Next chapter in 'How to destroy house in 3 easy steps' is coming shortly to PH near you.