Nickfromwales

They say it’s akin to pva. Not sure where that sits in the periodic table? 👀

Is this staying as the long term solution? If so, time to add the second pump and a 25L volumiser, and max out on efficient operation / longevity. Or, get a cheap as chips ASHP and put good money after good. Can you install the house ASHP there and export heat to the new build later on, via an underground pre-insulated umbilical, when you do the house? The one ASHP can then heat both spaces / buildings.

Bad idea. Keep heating and hot water well apart. Just use a 50L volumiser and a very small heat pump. Why not go to a split A2A setup and have the bliss of AC to compliment the bit of heating you need? Then just use cheap electric to heat DHW in an oversized UVC.

You can ask the timber merchant to cut the 8x4 down to 4x4 to make it more manageable. If you’re doing this yourself, you’ll have bigger balls than most! Good luck, and make sure you search this place for plumbing tips etc, or just ask more questions and we’ll do our best to try and not let you feck it up.

I’ve just done an MVHR retrofit in quite a large, 3-storey residential home, and you’d be surprised how you can blend a radial system in to an existing house. You can use multiples of smaller bore ducting to replace one larger one, for eg, with duct sizes down to 50mm, 75mm (and 92mm being the largest you need for radial). No need for rigid 100/125/150 etc, as all the big bore stuff is at the unit only. Two left ducts were fresh and exhaust to atmosphere. Right hand pair dropped under the unit via 2x acoustic attenuators to the manifolds. And that was all in a very compact cupboard space. This is 3x 92mm ducts, soon to be boxed, plastered and painted to allow them to blend in. Transfer grilles are a great way to cheat out of getting a duct to a particularly problematic space, but the caveat is needing higher flow rates in the room that is then sucking or blowing through two. Oversizing the unit is good advice too. It’s doable if you get someone with a bit of an engineering based brain and some tenacity.

lol. Carted a few around and my bollocks are still in mint condition Most would have a +1 on these jobs.

Defo overkill to have an IC to do this. Option B is a plenty good enough (normal) solution, afaic.

Bingo.

As always, you get what you pay for @HighlandWoman ask questions of the quality of the plywood, and get a good installer.

If I was going to buy 18mm ply and then pay someone to fit 18mm ply, I’d at least want to consider going to 25mm and see if it was a much better, long term solution, than to find 18mm was just ‘ok’. UK b regs is a “standard” it’s just a totally crap standard and the worst job you can do legally. Nothing to strive for!! If a few more £10’s can make an ok job into a great one, and then that negates the plasterboard, then on paper it would be cheaper and better?

And?

Do you have a picture of it? And if it’s small, as above, just leave it alone as joists can be drilled without compromise, and tbh a filler would only be for aesthetics.

Go for 25mm plywood? These grab rails may have to prevent you from taking a tumble, so I’d have this done properly first as last. If you tank the plywood then you can tile straight to it with a flexible, cementitious tile adhesive. Do NOT let anyone use ready mixed acrylic tile adhesive here, whatever you do!!! This stuff is crap, regardless of what promises are written on the side of the tubs.

Not seen one yet, but I live in hope that they’re out there, somewhere, but seems like finding such a conscientious architect is like trying to find a Yeti in a snowstorm. Seems you have to find the best possible one, and look further into what they’re doing for you to identify the gaps or omissions; not easy if you’re a novice, and something I am still amazed at when I’m introduced to a project after the architect has already ‘got the wheels in motion’. Thats great, if the wheels aren’t fecking square ones.

Is this a cable back to plant or a local 230v supply that’s off a local circuit? I always run a unique cable from every single corner of every opening back to a centralised location. This way I can send AC or DC to each unit, according to what’s needed. If the solar / battery solution works for now then great, but they won’t last forever. If you can match the voltage then you’ve got the option downstream to send it some juice from a transformer, if there’s a dumb cable run to it. If they were cheap enough then maybe the cost to replace them, with like for like by whomever, when the time comes, may be acceptable.

Ouch. The money shot for you will now be airtightness afaic, as with possibly compromised insulation volume you can still get a very well performing dwelling with AT and MVHR, as with a draughty house you can have 500mm of rock solid insulation and still be sat in the cold.

First unit was the fan, the second was a 3 stage, digitally controlled diesel heater. It was a very cold day, and it was very reassuring to see that they heated the incoming air to aid the process. Only negative was that every single flat surface, and I mean EVERY one of them, gets a layer of product left on it. This included the screeded floor which was like walking on fly paper for the next 2 days. I was horrified when the team prepped and just laid 2” masking tape onto the flat sections of the new Norrsken doors and windows……with zero dust sheet or other over the glass or vertical sections of the frames. All these guys did was throw poly sheets over the precious stuff and get to work. My only criticism was that this could have been better, and a few things got residual goop on them that I’d have preferred they didn’t. Was this a problem? Nope. It just wipes / washes away pretty easily, so things like pipes and lagging in the plant room will need a bit of cleaning after, which is fine. Just could have been avoided with some better prep. This was the first time I’d been on site during one of these treatments, so next time I’ll do the shitty (more intricate) masking / sheeting ahead of their arrival. In one of the pics you’ll see a tripod near a window, and that was guffing this stuff out at a rate of knots. I inspected the window after AB stripped their seemingly rudimentary masking off, and I can report that there was absolutely no evidence of them being there. This stuff just doesn’t stick to ANYTHING vertical. Not one bit. Happy days! All told, a great team arrived on site, they were speedy and got straight to business. Prep was done (looks a bit underwhelming but does what it needs to) and they were off to the races in no time at all. Quite an impressive setup with no reliance on electricity etc; as seen they just plonk gennys down and get on with it. I’ll defo be using and promoting AeroBarrier, anytime it’s the obvious choice.

No negative testing as AB only blow. I inspected a lot of the areas where this stuff had done its job, and there’s no obvious threat of it getting loosened by a negative test. It’s in that masonry and any such gap like swimwear! AB test certificate isn’t good enough for you to provide at the end of the build, eg for your “as built” AT score, so you’ll need to do another. The as built test is an average score taken from 10 positive and 10 negative, if memory serves me correctly. I asked the chap there and he said it’s something they’re looking into atm. The bottom line is, I’m seriously impressed by this system and the results it yields in not much time at all. You must fill the obvious gaps up, and do as much as you can to get the best results possible, but this will do quite a good job even if you’ve been lazy I expect.

They price per m2 iirc, and I asked the same question. So no matter if you’ve parged the place and use very little product, or you’ve a woodcrete ICF or bare masonry structure, price is the same. The larger holes? Well anything that you can see should be dealt with beforehand as best you can, obvs, but to give you some idea of how good this is, bearing in mind this product gets atomised, the results can be seen here. Look for the marble lines in these pics, and the ‘hole’ in the first pic, that was not obvious to the eye, got plugged PDQ! @Mike I’m referring to the ones that your method just won’t find, not the ones it can. Have a look at these micro fractures in the pointing of the masonry, and where masonry meets blocks. The blocks / bricks themselves are surprisingly airtight as is, and no real evidence of the product having sealed them, but I’m sure it has but it’s just not as easily seen. It got into gaps thinner than a cigarette paper, as you can see right at the bottom of the last pic. Two slight white lines 10mm apart or so, which the eye, candle, or other, wouldn’t have ever detected. There was a 3.4m long metal lintel which was perforated with hundreds of 6mm holes, and this stuff went into each one and plugged them up nicely.

Let’s be realistic? Going around on a windy day with a candle isn’t really going to cut it . I’ve recently been working on what is basically now an EnerPHit refurbishment of a mid 60’s brick and block bungalow. I advised the client to go for a posi joist roof, with an AVCL internally. At the tops of the masonry walls we parged 300mm or so with standard set tile adhesive, after SBR primer was applied to the new thermalite blocks / original masonry. That was covered in Passive Purple, primarily to act as a quality primer for the AVCL to get taped to. At the junctions between the kicker blocks and the infill screeded sections of floors, we injected 330 foam and then multi-tooled off the excess. This was spot foamed and trimmed again. Then the screed was primered and the sole plate of each internal stud and 100mm of screed against the plate was PP’d. Then these got taped over with an 80mm tape. This bit was prob overkill seeing as AeroBarrier were in next to “seal the deal”. The brick / block / masonry walls were left untouched, just a bit of foam and some leftover PP applied to the obvious bits. No additional parging necessary. Started off at a respectable 1.2ach, and that was down to 0.5 at 38 mins into the treatment. It got down to 0.2 by about 2 hrs in, and then the chap in charge decided to go batshit crazy and upped the fan pressure to 200pa (from 50); he said “we don’t see these types of projects getting such good results, so let’s get it to a 0.1”. And he did. 👌🤝👍 The only piss you off was the laptop didn’t do 2 decimal places, so let’s assume the 0.1ach was something like 0.18, so on the rebound I can say it was definitely a rock solid <0.20ach final test result. Shit hot afaic, for an old masonry hybrid refurb. Around doors and windows, all that was done was the foam, but the windows did get taped afterwards; whether they actually needed this afterwards is anyone’s guess, but for longevity, they got taped a few days after. The roof lights had the splays done in the green propassive AT OSB, and they were taped to the AVCL and then the OSB was taped to the roof lights. This was after Gordon Lewis had been to work his magic, fully filling a rather complex roof structure. He was VERY thorough and even came back the morning after; he was supposed to have been elsewhere, but wanted to go around one more time so he could just work some of the smaller, more awkward voids to his then satisfaction. In a nutshell, he stayed until the job was done and 100% over the finish line. Big thanks and a shout out here to Gordon, so anyone wanting Warmcell blown in please PM me and I’ll zap you his details. FYI he tapes up everything after he’s done, so an AT tested build will still be AT after his attendance. The AB product is more like PVA than caulk, so it’s stretchy and won’t crack or fracture like caulk does. They were adamant that taping the doors and windows was pretty much a waste of time / money. I’ll post some pics in a bit. Places where this got in and sealed up were quite fascinating to see (if you like that kind of thing).

Winner winner. Looks good, and almost as if a professional did it 👀😄 ”Result”.

A solid section of XPS board, and zero battens. The talk of battens has left the building, and is not coming back, which is my lame attempt at a subliminal message. To reiterate. Battens = 🤐 You can have this floor 10-20mm higher to get more insulation in, that’s a good idea all round. A decent chamfered timber (hardwood) threshold has been great a way out of many similar transitions that I have done over the years. Works a treat. UFH over the XPS tile backer boards (no place for Hardie type boards here sorry) and then the least amount of SLC as possible, then the flooring. For stone, you can just lay on a decent bed of flexible tile adhesive immediately over the SLC. Or, if you’re brave or are paying a tiler, they may be ok to simply lay the tiles straight over the UFH wire / mat and save you having to use the SLC at all. That’s down to how much undulation there is in the subfloor as this will be represented above the XPSc as that will be bonded down, again with flexible tile adhesive. You can use that first layer of adhesive to remove any undulation, which may be another way of reducing layers; you can then do away with the SLC if the prep is good as above.

lol. I suggested similar to a client once, when younger and even dumber, with glass mosaics. It was a never-ending punishment to lay, and then the grout just refused to dry as I’d made it a bit wetter than usual (to give me some more open time)…… Then, whilst stood in the bath grouting and buffing like it was my last day on earth, I bent over and head butted one of the sharp copper pipes I left for the shower (with no cap end) and still have the Harry Potter scar on the top of my forehead; I am now ever-reminded of that “fantastic idea” I once had. ffs. 🤦‍♂️. Long live the large format tile!

Another for the KISS approach