Nickfromwales

No need to spit on it, just sand gently and paint 🤣 It's Saturday night ffs, and if anyone's posting here whilst sober I want their name, rank and number so they can get a proper bollocking.

That should read "tape & joint" aka dry-lined, as that doesn't have a wet plaster coat. Dot & dab is how the boards are affixed to the underlaying wall and taped and filled joints are the ones always visible forever aka 'shart'. I can recommend a fantastic plasterer in the Coventry and surrounding areas (he'll drive an hour or so). PM me for details.

Yes. Can you get a spirit level or other straight edge and see if the top of the window frame is deflecting downwards (bends down near the crack)? Best to ask a fitter to find out why the window cracked when they call out to remove the glass to survey it for size and type (they'll have to do this to order the replacement anyways).

I am suggesting you double-barrel the ASHP's at the same location, with the same plumbing, to keep cost and impact down (referred to as cascading). You simply do not have enough kW of 'oomph' to keep up with the fabric and ventilation heat loss at the new, significantly lower flow temp.

Do you know the installation methodology of the UFH and thickness of insulation? If the system is otherwise working A-OK, does it still not then get to 21o?

I think you need a new SE tbh. I doubt they have much experience with this type of arrangement unfortunately. This Larson setup is a-la MBC TF, have you seen their website for examples of how this is achieved? My current clients build is with MBC and has a brick plinth, and the outer skin of the truss sits atop the EPS so no cold bridge. The EPS footing blocks come with an extension, to provide a concrete strip for the brickwork to sit on.

Have you seen concrete screws? They go through the timbers and straight into the concrete floor. Drill with a 6mm sds pilot, clear the hole a good few times to remove debris. Drill at least 3/4 of an inch deeper than you need. https://www.screwfix.com/p/easydrive-tx-countersunk-concrete-screws-7-5mm-x-70mm-100-pack/9643h?ref=SFAppShare

Yup. The liquid will get through, then lift the trays. Just gas nail pipe clips down maybe? That’s over solid concrete, 22mm gas nails into the strips. Was very quick going down tbh

@london8 Is this the only form of space heating in the house? Does it not have central heating? I think you’d be better off with a pair of oil filled radiators which have a bit of smoother output vs just on/off like halogen / ceramic or radiant heating does. To answer your specific question I do not know of one. @SteamyTea linked above to the nearest thing to what you have asked for I think. 3000w running constant is going to be very expensive to run though.

Is the pipe sealed well with a good external grade mastic? Also, note the brick vent set into the wall, another possible cause or point where rainwater may be getting driven in. Water / damp does very mysterious things, unfortunately, but could you confirm if this is a solid brick wall without cavity? The air brick makes me wonder, or is that from an extractor fan / other?

Feck or bollocks is fine. Let it all out. Id recommend putting a good quality lining paper on first, as oil based stuff hates taking emulsion. Wallpapering would hide these sins far more robustly.

This is the only way I’d ever install a system for a domestic client. One previous had a huge garden and were almost a small holding, chickens / veg gardens etc, and when the ground-workers were there with a 15T machine I suggested that if they did want to do RWH they should install 2x 5000L tanks whilst cheap (cost-effective) to do so, exactly for the reason of not ever running dry or as near to as dammit. More solar PV went on instead 👌. I said it’s pointless going for anything smaller as it’ll not pay back over time, but sadly there are some great salespeople about….do your own maths people!

I’ve used Compacfoam under the doors and sliders, on a previous job (where I had to removed poorly installed units and refit after the installers made a piss-poor job of it all and disappeared). Very good stuff, just need to see here exactly where the cold bridges exists and how deep the product needs to be to created some separation.

Yup, I think mostly aimed at / suitable for more adverse installs, particularly where freezing is going to be a known issue.

To do this properly, the idiot you called out should have purged every loop with cold mains water (to blast the air out). The problem you face is, the pump will move water through the UFH pipes at a snail pace, so if all the loops are open you can divide the pump power by the number of loops. You need 100% of the pump on each loop individually to stand a chance, hence my advice. Best I can offer at 00:25, but I’ve got 4 kids and I don’t want to see you or them freezing your rear ends off. Go see the ‘technician’ that called out to ‘help’ and kick him in the testicles. Twice. As much use as a kickstart on a submarine.

Each loop needs to be on for 20 mins to bleed itself, this assumes the automatic air vent is open. You start with all other loops off, actuators all removed, and then bleed 1 loop at a time.

So, I think you are now airlocked throughout. Quick hack; take every actuator off except loop 1 (you choose), and then run the system. Wait for 20 mins to bleed out the trapped air, then open loop 2, and so on. Most advice I can give you tonight I'm afraid. Genius. Useless w8nker I hope you've not paid for this disservice?!?

If you're going for a quality result, then "why have cotton when you can have silk"? Down to price I guess, so maybe mix & match at the openings for the best overall result (when factoring in a sanity check).

I dislike the porosity of the thermalite block, so it wouldn't be my choice vs Marmox (which has a miniscule value for porosity in comparison). A 'wet' ("atmospherically moist") thermalite block will bridge cold significantly more by comparison.

If you are suggesting a retro-fit of a RWH system, then I'd bet my left nut that over the next 20 years, the cost of install / maintenance / pump replacement et-al would actually be a very different figure.....

So is this 9" wall brick with no cavity? I expect so. What you have here, sir, is "penetrating" damp. Find the epicentre of each problem area and get the drill out. This will get messy and worse, before it gets better. This isn't a rising damp problem, for sure, just rainwater finding its way down through the old mortar perps and into the interior surface of the wall, or, is the same thing you see with older walls that have knackered, corroded cavity wall ties that are then bridging the damp across them; you can almost find the fault to the nearest 100mm.

🤣

Mothers milk

If it doesn't, neither of us will wake from our deep sleep tonight, but if possible the two should overlap Will any of this actually matter(?), remains to ever be documented and evidenced in honesty. For the sake of the polar bears, fit the 100mm is my 2 cents.

Let this follicley challenged chap explain.... Random grab off the interwebnetiness