Conor

I need to order clip rails this morning. Don't have time to go though all the drawings and figure out how many I need. We have 180m2 in total of UFH being laid with 900m of pipe at 150-200mm spacing. From what I've read the clip rails should be spaced every 1m? So in my brain that's 180m of clip rail unless I'm being thick?

A bit more from me. We went with just the self adhesive membrane under the slab and up the icf walls. Was told this would be enough. We have small amounts of water appearing at the corners of the slab. We're not fully rendered yet or have thresholds finished... But it's given me enough of a worry to not finish the basement now and instead put in a cavity drain system and drill a sump. I would not rely on the membrane alone nor the concrete core and instead ensure you have two methods - i.e. a cavity drain and sump.

We're using it on our intermediate floors before we lay our ufh. It works out slightly more than PIR but that's before you factor in the faff of laying the boards flat on uneven slabs. If using it for you gound floor insualtion, you need at least double depth compared to PIR. No prep or membranes required on intermediate floors - just shuttering voids.

The limit will be the weight of the building above and the rating of the EPS used. We wanted an insulated raft, but our three story icf design was (according to our engineer) too heavy for the compression limit of the EPS. We would have had to use much bigger ring beam to compensate, which wasn't an option due to the limits of the excavation. So we had to go for a normal ground bearing raft.

I know to avoid putting wet ufh loops under kitchen cabinets, shower trays, baths etc. But what about wardrobes and other semi permanent furniture? We have low eaves on our first floor (1.2m wall plate) and will eventually put built in cabinets along most of these sections in bedrooms. Is it ok to put UFH loops under areas likely (but not certain) to have built in cabinets? Would only be used for storing linen etc. Can't see an issue myself?

Welcome! Admire your principles and best of luck.

I'd presume they could be caused but the filings that come from when the nails are fired?

Top tip from our supplier for working in cold weather.. Store the rolls in a warm house and install quickly before they cool down. Use a heat gun for corners.

I used Larsen multi grout 60. Flows like hot oil. Just make sure you have it well shuttered or else it will flow out.

@cwr cant honestly say. I do know they need dry and mild weather to apply the top coat. good time of year...

We used a bitumen based self adhesive tanking membrane. Fairly standard, just need to protect it before backfilling.

We've started rendering with Sto standard white. It's stunning.

Can highly recommend a subscription to passive House + mag. They quite often have energy usage data with their case studies. Not sue of they have them online. I'm in to year 2 of a free 6month subscription trial lol. My architect advised me to assume double the demand figures when deciding on a heating strategy. Double of not very much is still not very much.

Been through this as well, all AAVs ok for my BC guy

I doubt it - you'd need equiv of a full height 800mm unit for a slimline 150l tank, and another 600x800mm cabinet for a 60l buffer tank. and a bit of room between for the pipework. I'm using a 2m wide wall in my utility - floor to ceiling. Do you have space under your stairs? Hate to say it but a gas combi would be a neater option.

When I woke up at 3am worrying about my own build, this popped in to my head as well. I echo what @Moonshine said about CDM. I'm a designer and engineer by trade. Safe constructability and maintenance of works is the number one consideration when preparing a design. 90% of my experience with laying pipelines in deep trenches. I know all about how things can go wrong. I'm really worried that there is a reputable firm proposing a design that is so blatantly dangerous and cannot be undertaken safely (or at least they have not shown how it should be undertaken). I would be asking them directly how they have come to this design and how it incorporates CDM requirements. I could never propose a design like this. It requires somebody to enter the excavation. There's no room for proper shuttering/trench support and they've not shown how the sides of the protection are to be secured and how machinery and personnel can operate around the open excavations. It's their responsibility to design this. If there was an accident, I'd be expecting the designers to be prosecuted. You, as the client also have responsibilities, so do not accept this design. I'd speak to the neighbours and see what they did. But sounds like you are tied to this firm?

Would be easiest to fit another layer of 11mm OSB on top of the deck? No messing with noggins.

1) Yes it is - confirm the pipe diameter requirements with manufacturer 2) Find another installer. 3) There's no reason at all you'd NEED to get a split system.

We had a call with LV today, from what the rep said, they don't really care about the construction type and treat them all the same and didn't blink when we said ICF.

You'll need to use trench boxes. But they are difficult to setup in narrow trenches, and you need people that know what they are doing. There are many practical challenges to digging that deep in a confined footprint. You'd likely need to dig, shutter, pour, temp backfill a section at a time. A huge factor is the soil conditions and specific modulus. Your engineer/designer should be designing something that is safe and practical to construct - fundamental part of CDM. How are they proposing it should be constructed safely? I would absolutely not be digging trenches that deep and narrow for purely practical and safety reasons. I would be pushing for a different foundation design - eg a ground bearing raft with micro piles, if needed. This may mean a different designer/engineer.

I use screwfix for all above ground stuff. local builders merchants for the 6m underground pipes.

Not installed it yet unfortunately... Will be another couple weeks I'd say.

I decided to move my car trailer with the telehandler rather than get out of the cab and pull it.... Of course it dropped off the forks at the highest possible point. It did not end well for the trailer.

Dial before you dig will tell you what utility companies have services in your search area, you can then go to them individually for maps of needed. But services to houses are notoriously unreliable.

Those U values don't sound right. For that size unit you'd expect to be around 0.8 for 3g.