BadgerBadger

Thank you - just looked it up and the 8kW looks to be R290, which we can't have unfortunately as there's floor void/air bricks next to it, so are stuck with R32!

Let's go with "confident it's appropriately sized". Design heat loss is about 5-6kW at -3C, I could squeeze into 6kW but could be marginal if house performance isn't quite as per theory, so we're going with 8.5kW Ecodan. Annoyingly I've already paid/lost survey & design fees to another installer whilst chasing the grant, only to hit a dead end with design there too.

We have a good well-insulated airtight build with MVHR etc. UFh throughout downstairs so have decided to skip the complexity of heating upstairs, as all the feedback we hear is that it won't really be used. But we're having trouble accessing the BUS grant for our ASHP as the installers models are showing undersized emitters upstairs. Heat pump is plenty big enough to cover total heat loss. Have others who've done the same had similar trouble?

We used it for our DPC (no radon barrier) and it was good, notably thicker and stood up well on-site where we left sections to lap dpm onto later. That said it was harder to form shapes/bends etc so we used thinner stuff for cavity trays above windows etc.

Were you paying the electricians directly or were they? It sounds very ludicrous and unreasonable, which just makes me wonder if their understanding is different from yours for some reason.

What was your agreement with the builder? Did they give you a price at the beginning that they're now invoicing against (stage payments along the way?) or did you agree something else?

Hi all - we're about to install acoustic insulation in our 400mm centres posi joist floor. But I'm not sure what the best size/product to get. I can get Rockwool RWA45 but only in 600mm wide slabs, is this going to be really wasteful/awkward on 400 centres? Can a stuff two offcuts next to each other and they'll hold in place, or should I be cutting the slab widthways and laying smaller pieces. Alternatively I can get Rockwool Flexi in 400mm wide slabs, are these going to be easier? As ever in this self-building game I'm pretty sure I could work this out by trying for a couple of hours, but by that point I'd have ordered a pallet of the wrong material! 🤣

Our build has beam & block floor with masonry cavity walls, the inner leaf extra wide DPC was built in and left hanging ready for the DPM to be joined to it. That time has now come! 😅 I'm getting mixed messages on how to seal the DPM to the DPC. Should I be using the double-sided butyl strip stuff between the lap, with extra single-signed DPM tape over the joint? Or is something else commonly done? Similarly, if need to join to sections of DPM I've heard everything from "just overlap it lots" to the same double-taping as above.

I have hired plant cover as part of my overall site insurance, was a relatively modest extra if I remember.

That's what I've been telling my wife when she asks why the glazing isn't happening 👍 😂

We turned our attention elsewhere over the summer, the frame is in but we haven't tried to glaze it yet. About to take delivery of the door from joiner, so will try in next couple of months and report back. (Give me a nudge!) Worth noting - we've had one very large split on a piece in the frame over the summer that's going to need sorting before we glaze. Good example of the sort of "risk" you'd otherwise be asking a contractor to shoulder.

Welcome - let the username confusion commence!! 🤣

Quite a bit, there's about 30-40mm of frame over the outer leaf and the rest is in the cavity supported by the brackets fixed to inner leaf.

Thanks all - so general consensus is there's no set solution and I need to work something out 👍 Variation in the brickwork reveals mean the gap to build-up is different on every window, need to get airtightness sorted, and aiming for bullnose plaster corners too 🫣

Rational windows are in, and have been fitted to internal block work with brackets. But I seem to be a bit stuck on how to finish the internal reveals? All my drawings just show insulation material around the brackets with plasterboard on top. But any ideas how I actually achieve that?! Rest of the walls are wet plastered.

Reclaim hasn't been submitted, but I've making sure I follow up with all suppliers and get a proper VAT receipt after payment 👍 I've had various proforma invoices issued from companies along the way that i haven't gone ahead with for one reason or another, so fairly understandable that HMRC can't accept them as proof that VAT has been paid.

I think I'll aim for middle then!! 🤣 Thanks

So are you on the "cold side" of your insulation? As you say, would be good to keep well away from UFH even though our flow temps would be relatively low. I had though of running them pretty much on the beam & block, with majority of insulation over the top but was concerned about freezing. That said, not sure if the beam & block would actually ever really get towards 0 degrees.

I'd like to sanity check a plumbing plan please! Our kitchen is in a high vaulted space and quite a long way from the plant room / UVC. So my options for pipework is 1) a convoluted route up through the loft, along a service void in the vaulted ceiling and back down wall to the kitchen or 2) a slightly bendy route, but somewhat shorter, route under the floor screed. Floor buildup is beam & block, 140mm insulation and 55mm liquid screed with UFH. Pipe runs will be single length of plastic pipe with no joints under floor, in narrow duct so they are theoretically replaceable to meet water regs. My current thought is to put them in a channel in the insulation, with some thin insulation covering them to give a bit of separation from the screed/UFH. Does that sound logical, or any other ideas?!

We were in a similar situation and did all of groundworks and substructure without mains. Relied on neighbours with a hosepipe, a m3 of water is really quite a lot so we just sent them a thank you card, box of biscuits and £20 once we were connected. We filled big blue barrels of water for the brickies to use and had a chemical toilet in a shed to save on portaloo hire (which adds up very quickly) Got mains sewer connection in very early, so I could empty chemical loo on-site. Only once did I have to put it in my car and take it home, not recommended!

If it helps, you could look at getting your own slips cut down from regular bricks. Might give you a few more options with local brick cutting yards.

I'm fairly certain you're not allowed to stack marmox thermoblocks on top of eachother, they have to be single layer.

Looks nice! It's a long way from developer site box-shape though so don't underestimate it's build complexity. My advice if you're going direct with trades is you will need to be across all the technical details, there's money to be saved but don't forget you've cut a level of expertise out that needs to be filled. I found people can be a bit blasé about the difference between contractor led vs individual trades build routes, and we very nearly got caught out.

Is your build straightforward, or is complicated? We had a complicated build and did all our brickwork on a mixture of meterage and day rates. I must say managing our brickies was probably one of the hardest parts of our build so far, we got through a number of gangs and the amount of technical input they required was high. My preference would be to be on meterage, and fall back to day rate for any complicated bits. (you know where you're at financially, and they're motivated to work hard - but you need to keep an eye on quality)

Just looking at this yesterday! Planning to parge coat top of blocks to get a smoother finish, then masonry airtightness tape (eg Solido SL) to seal between wall and ceiling insulation foil. Wet plaster to finish on walls. No idea if it's a perfect solution or not, but seemed pretty good for the price of a couple of rolls of tape.