Nickfromwales

Was more worried about rats / mice than insects TBH. And I assumed closed cell would be the weapon of choice, but I've no direct experience of the products, other than in a marine environment, so best the OP asks all the questions to the installer and that they get a warranty that reflects what they are told, re suitability and longevity. Have also seen it used on battered roofs with great results. I assume they will staple on some sort of fine nylon webbing / other to the underside of the joists to catch the liquid from falling down between them whilst the first lot expands / cures, so wondered if that may as well be a metal mesh first as last. Never seen one done in honesty so don't know exactly how they execute such an installation, maybe they just build it up in layers as the stuff does expand crazy quick. Anybody?

I never use PVA as it will reconstitute with water. Flexible tile primer is the norm. Yes, once in you can just jam the gun nozzle down the sides IF you have a gap to allow you to do so. Perhaps once the tray is 5mm or so away from its final resting place you could mask it up, nudge it far right and pump a load of sealant ( NOT SILICONE!!!! ) down the left side, then do vice versa, possibly the same bringing it forward so you can seal the rear, and then just centralise the tray and top up / wipe back sealant until it's all uniform and neat.

You won’t be setting the tray into notched adhesive, instead you’ll be resting it on piers of tile adhesive and just setting the tray down into those ( as the tray gets tapped / twisted south the adhesive will spread out and give much more coverage ). That will make life a lot easier if you insist on this being a one man job, and will give you quite a bit of play time to set it to the exact depth and level. After tapping down into place the tray will stay put, as long as the adhesive mix has no, or very little slump. When mixing, you push a stick into the mix and withdraw it, and the peak of the adhesive left should stay. The peak may fold over under its own weight but the mix should not return to being flat in the bucket.

A dangerous game, as that can cause the tray to crack later down the line. There should be no single point of contact between the substrate and the tray.

Mapei or Ultra. Both will do the job

Hi Edward. The guys on here are striving to get the best solution, so they answer according to that ethos You're not doing anything "wrong" just there are ways to go about this which will yield better results. Infiltration will be the killer here, so you really need to stop the focus on insulation and look closely at draught-proofing, against the ventilation heat losses you will have with the cold ventilated void, and then you wont have to be so critical when the insulation dilemma gets decided. Spray foam is a good way to address both issues, as long as the detailing is correct, so you need to ask the difference between open and closed cell foam and where they should be employed to make sure the timbers don't end up sweating. Ask about insect and vermin barriers also, as insulation is a friend of the tunnel bunnies.

Apparently there's a company in Kent now offering speedy turnkey wetroom installations......................................................

OK. So, in this instance what you do is make nice pyramids of quite stodgy tile adhesive ( slow set !! ) and have then about 50mm higer than you need the tray to be. Then you slide the tray out on battens, or lower it from the front onto short battens near you ( there so you don't lose your fingertips when the heavy slippy tray gets the better of you ) and just let the adhesive squish out as you rubber mallet the thing into the position you want. Lots and lots of small taps, and never in the same spot more than twice, and gravity will go from your enemy to your friend as the tray heads south to its final resting place. Sort the waste out after its gone off, and plug the missing block with expanding foam. Then you just mix 2-part self leveller and pour it into the void around the blobs of tile adhesive under the tray and let it fill up as much as you can underneath. What could be easier?!?

He's screwed....lets just delete the thread and pretend he never asked

I've never used sand and cement mix to bed a tray down, just couldn't think of any reason not to use a flexible tile adhesive TBH. Remember to clean the underside of the tray as it may have decoupling grease / silicones etc as a residue from the manufacturing process, and tile adhesive won't stick to that. Oh, yes........ in your instance I would stick it down with tile adhesive Get some of the tile adhesive and a sponge / rag and make a paste to use like a cutting compound and scrub all the underside with it like as if it were Ajax. You'll see where it wouldn't stick, and when it then does stick, and then clean the worst of it back off ( unless you time this process with the overall laying of the tray ). Don't use your huge balls, switch to the iddy liddle ones and go with a standard or extended set adhesive so you have hours of 'play time' to get the tray scrubbed, buttered, substrate notched / blobbed, and the tray fitted to suit. Your time starts...........................................................................................NOW!

Pinged this only the other day. Have a read.

Making an energy efficient home shows that they care

Deffo apply to the internal if you stand any chance of getting some integrity there. Forget the attic as that'll be an absolute nightmare to detail successfully. Have you also thought of over-boarding the ceilings joists with 30mm PIR boards, foil faced, and then use foil tape to complete the barrier. Two birds one stone.

More PV???

Light plus waste heat?

That is trapped. Will have a removable ‘flap’ at 45 degrees inside for maintenance.

Galv buys you a few extra nights sleep no? Serious food for thought there. And which one of these are willing to put their balls on the line and offer warranties reflecting what they say? And how long for? This is a significant decision, and one not to be taken without the backing of the company supplying as 'fit for purpose'.

Quote: "The area where the undersoil tube is laid should not be built over so it is guaranteed that seeping rainwater can contribute to the thermal regeneration of the soil".... so anyone thinking 'kill two birds with one stone' on the dig-out for the dwelling, nope, it has to be outside the build envelope. One client I had simply dug extra deep around the periphery where rainwater systems were to go and economised that way.

The one I worked on seemed a robust setup, but will only work as well as it is installed eg buried the correct depth and in suitable ground. I also introduced a PHE and a couple of zone valves to introduce heated water from the heating system into the same BPC duct heater / cooler. Effects were instantly notable in 'heating mode' and I expect it would work well as a passive unit also. At that price, nothing stopping you doubling up and fitting 2 lots of the kit with the duct coolers in parallel for larger properties or higher yield.

Not overly expensive if you have a machine on site

And the only way to find out, is to go and ask Some people will appreciate a binary dialogue, others will run a mile ( ask me how I know ) . Persistence will pay dividends but never struggle to engage, as that should be organic and mutually enjoyable Do not expect anyone to change for you as that is just never going to happen, so make your decision and go ask for a date. If you don't ask, you don't get!

Pack of 3 blades for my Makits 18v cordless circular saw for £20, and just bite the bullet with the dust.

More words of inspiration....

Today could be your LUCKY DAY!!!!!!!!!

Not mine either. I genuinely was shocked at how noisy the internal unit was. That was fitted in a basement and with good reason. There would be no way a customer would have accepted that inside the kitchen, the utility MAYBE.... Mono-block for me every time, and do away with the need for high temp delivery ( eg heat DHW off overnight 5p electric tariff ) and just use the HP for space heating.