Conor

No, just get it done. Ours was done in December. we only had a small area wash off. The silicone renders cure quickly, even in the cold.

We did it exactly as your building is proposing. If you don't have insulation, fitting the UFH is harder work as you have to attach to concrete rather than soft insulation. yes, perimeter insulation is needed as acts as an expansion gap.

So is all the driveway drainage going in to the aco in the middle there and then to a soak away? Where does the water go when the aco and soak away are overwhelmed? I hope there is flow to the road? Otherwise your house will flood. BC would not accept our patio drainage for that reason, we had to install a separate set of drains incase the primary got blocked or overwhelmed. And indeed, it's happened once that i know of. And agree with Jimbo, you're going to have damp issues all along the front there. An alternative is to install an aco channel drain all along the edge of the house, rather than the bricks. No caps on channel is fine if thet are up against something solid. Would be an issue if loose material could collapse in.

Where is the water coming from? If you're going to cut out and relay, I'd fisning the new surface 5-10mm lower, then come back a week later with a bag of self leveller.

Turn flow rates of your ufh zones down a bit.

Is your heating system working as expected / adequately?

Drill a couple small diameter holes through the door frame on each of the three sides then insert something like a small Phillips screwdriver until you hit the masonary to determine the depth, and therefore the true width. The holes can then be easily filled and painted over.

You won't be able to claim the VAT back on this work unless it's on your planning drawings. Go back to planning and get it added in, if you want to keep it. Otherwise it'll have to come down. So you have your planning passed yet?

BC and other parties were happy that the concrete in the ICF constituted adequate type B. I dont think I'd trust it in a full basement with hydrostatic pressure. In a partial basement, the tanking is more like a glorified damp membrane, as you SHOULDN'T get any hydrostatic pressure for any period of time.

You don't need the internal membranes or drainage. Money for nothing. If it's a partial basement, with perimeter drain and clean stone backfill, then the external membrane and continuous, consolidated concrete are enough. Our partial basement was 200mm ground bearing slab (300mm ring beam) with tanking membrane underneath and on top of compacted type 3 (permeable) stone. So same as your details above but without the internal systems. We've had zero issues in the last four years. We used Koster. We than had 200mm insulation and 50mm screed with UFH on top of the slab. Our SE couldn't get a insulated raft to work as would have needed EPS300 throughout which was cost prohibitive. We've 2300mm head height in the basement. The absolute key thing here is, you've two sides open, which means as long as you've a proper drain, and loads of clean backfill, then the tanking won't reply come in to play.

All sorted in the end. Two idiotic moments turned it in to a bigger job that nesecarry. 1. I missed a second isolation switch for the control module on the tank. 2. A sticky valve on one side of the pump that I didn't fully open. All Woking good. I've a potential tiny leak tho on the Flexi pipe to the ASHP. I need a bigger spanner.

You want an architect on board BEFORE you go to planning. Are you going straight for full planning, or just outline (if it's an option?) What's the circumstances of the plot?

Take it back to the supplier, get them to cut it to the right size. Though you might find somewhere in the small print saying their tolerances are something like +/- 5mm....

Perfect John, thanks. @dpmiller have you done this before?

Standard working hours are normal in construction, so you are not alone. A few points. 1. Is there anybody close enough to you to be disrupted by work outside of normal hours? 2. Are they the type of person that would be annoyed and make a complaint? 3. Be considerate and don't take the piss. E.g I waited until hearing the church bells on a Sunday before doing anything noisy. If that lot can make a racket, so can I. 4. Speak to your neighbours, give them your phone number, ask them to say something if it's disruptive. Our neighbours both had young babies when we were building, so we were very conscious of that 5. Dust and smoke. Manag dust effectily, e.g. wet cutting. Don't burn anything on site. Ever. 6. Don't give people any other excuses to get annoyed - keep your site tidy, put up proper signage and contact details. 7. Use quiet methods / equipment when possible. E.g. hire an electric Tele handler, use a transformer rather than generator, electric con saw rather than two stroke petrol (biggest noise on any site). So cutting /machining inside. I used my shipping container for cutting timber as much as possible. 8. The council really don't care unless there are repeated breaches, only then will you get a letter / visit.