Nickfromwales

Bingo.

Your architect needs to enter into confidentiality regarding your project!!!! Bloody ecologist would have been asking loaded questions about your project to try and identify it. Have a word!

Nothing to worry about here, other than you do NOT use mortar. Flexible tile adhesive or builders screed (Mapei self lever with fibres), or for a full depth install a mixture of both. On my current clients project we’re doing both trays exactly as you propose. One over 250mm of EPS and the other over 175mm of foil faced PIR ( depths differ here with old + new substructure levels, as it’s a conversion at kind of EnerPHit level). Got an airtightness score of high 0.1’s, so happy to declare a definite flat score of 0.20 ACH for bragging rights. 😎👌. Firstly, 220mm of PIR is very good, no need whatsoever to get that to 300mm ; PH is achieved with 300mm of EPS don’t forget!! Diminishing returns say not to bother much past 200mm, which you’ve gone over. Anyhoo… Trays don’t ‘rock’ unless you’ve got that section of insulation cut away and are infilling that also, but if there’s full sheet material locked in 4 sides around then it’s going nowhere. My ‘trick’ is to use 150mm concrete screws to set into the main screed as catchers / rebar pins, so the infill of SLC / tile adhesive can bind to those. Zoom in and you’ll see these pushed half way into the EPS blocks I made as shuttering. You need to have these low enough not to interfere with the tray when set into the void. The blue expansion skirting wasn’t necessary around this, but the 3rd party UFH company did it anyways…. Down at the end is a buried 50mm waste pipe for me to jump on later, which all went in as 1st fix with hot / cold / waste plumbing all got installed / hidden below the insulation. I’ve set the waste pipe low enough to allow for the tray to be slightly recessed eg lower than the surrounding screed to reduce the step / lip left after tiling, however the clients have chosen very low profile pre-finished trays so probably only dropping those by 5mm or so to leave 10mm of shower tray showing above the tiled floor. All hot and cold feeds went in on a radial setup. Another 100mm of PIR got put down there after I sorted out DPM etc around the pita pipes / other obstacles in the plant cupboard. If you’ve still got an opportunity to get the 1st fix in the ground floor like this then it’s something to consider, as it makes 1st fix much easier imho, but more relevant here as it is a bungalow with vaulted ceilings / no attic void for services. Shuttering worked perfectly for the screed pour (liquid cement) Shuttering now removed and all walls gone up. Getting boarded atm ready for my very good plasterer mate to come and do his thing. I can post some pics of the trays going in but prob a week or more away from that yet. @Dunc when are you doing all this?

Architects are usually great at opening cans of worms, but afaic this is largely so you can’t come back and moan to them (or sue them) for anything they didn’t highlight. Were an odd thing, human beings, as we want one thing, but then get it, and then complain if we fall on our own swords This is why professionals highlight these things imo, however they should be communicating such information exclusively to yourself and then you can decide to action any of their recommendations, or ignore them, to suit convenience / cost / time. Defo not one I’d be waving any flags about for, so plod on sympathetically (and just tip your hat to the architect and silence them on the subject). It’s quite common for this type of over-zealous behaviour to end up costing my clients 5 figures, which is why I mostly promote the use of architectural technicians nowadays who are more grounded / pragmatic, so proceed with caution!

You just need to unscrew the bush too, which either leaves you with a 1/2 or 3/4” bsp thread. You then just buy the reducing bush for £2 and screw the vent into that. PTFE is your friend here.

Near the beds, as a fail safe. If the existing one is a few years old, replace it. ’vans rely heavily on the airflow through floor / lower wall vents, which most block up in winter, to allow gas appliances like cookers and fires to breathe / vent. Modern boilers are “room sealed” and have a coaxial flue to outdoors; smaller inner pipe ejects the fumes and outer pulls air in for combustion. Balanced flues need air from the room. Stayed in a large static once, and it was like a colander lol. Wife was paranoid so refused to let me leave the gas fire on overnight in the living room (at night this was the adult / spare bedroom) and it was like a fridge once that got turned off.

Needs to be equal pressure opposing on all sides so the fitting and insert don’t deform.

Weak concrete pads at the start and end of the run, and then multiples more every 1200mm or less will make life easier here. Be mindful that you cannot compact / whack anything retrospectively, so do as much of that as you need to, prior to installing the pipe.

Just use trapped gulleys on the furthest one, to manage leaf litter / other debris?

@flanagaj Beware the plywood skirt preventing ventilation / adventitious airflow to any gas burning appliances. Please tell me you have more than one CO1 detector in there? Oh, and congrats on being on site, just be safe!

You can cut the T out and revert to compression 16mm fittings to connect this lot back up. You use 15mm comp joints but they have 16mm nuts / inserts / olives to adapt from 15>16mm. A lot of decent merchants carry these nowadays if you just ring around. Not sure how much pipe drops out of the T so hard to advise. Can you take that bit of insulation off to show what ‘we’re’ working with?

Get another vent and swap the gauge out. You have one on the red expansion vessel control group where you fill / top up.

1). Why? You don’t need this. Just close off one side of each of the 3 loops with the manual blank caps and jump on the ends of the manifold. Simple and a zero spend / rework.

🫡 If it’s to the EV then is the intention for the EV charger to have internet connectivity or for the cat cable to get you a set of CT clamps back at the head / meter? Doing this for a current client atm, but was thinking to run a second (separate, duct-grade) CAT6 to the carport to offer up a future WAP there. Cables cheap enough to put a redundant run in (<35m). So the hybrid cable @Adrian Walker linked to, is that cat cable intended for CT clamps? Only now dipping my toes in the EV charger waters…..

It’ll also be an acoustically poor solution, so with moderate to hard rain the sound will be notable to the room interior. A blown-in insulation would be the very best solution for weaving around the metal webs and those associated impossible to get to gaps, and give a huge boost to sound deadening. As @ProDave says, this is something you need to stop all wires with and get a solution to, before moving any further forwards. Just had Gordon Lewis on site pumping my current clients roof with Warmcell (blown-in cellulose) and he’s done a fantastic job getting every nook and cranny packed full of the good stuff. 👌 Abandon the rigid insulation in the roof, and preserve that for the vertical walls only. Arcitect will need to rerun the intersitial condensation analysis before pulling any trigger. Airtightness is moot, the original house will underperform most likely, just all about draft proofing at this point; plus obvs managing repeat cold bridging, and maxing out on the (properly installed) insulation.