Barnboy

@Omnibuswoman hopefully it works, I've just rollered it on, it's odd stuff, quite thin but with a grit in it which will give the adhesive something to adhere to. The tub says to allow it to dry for at least 24hrs so that gives me a bit more time to pluck the courage up to fit the tray.

Thanks @crispy_wafer I'd seen this but my worry is that the adhesive won't take to the smooth shiny finish of the waterproof caberdek. I'm going to try priming the floor with some Thistle bond, a friend told me today that he used it when he bedded his tray down on a sand and cement bed after it didn't bond to the same flooring.

Ok, no answers but another question, Tile adhesive onto 22mm waterproof Caberdek, the grey smooth shiny stuff. Will adhesive adhere straight to this or do I need to treat it with SBR or similar? It's designed for bathroom floors so I'd hope it would be OK to go straight on but I rather do the job properly once. Thanks

Hi all, I have a Merlyn level 25 shower tray to install in our ensuite. The floor is currently 2mm waterproof Caberdeck which I'm looking at adding a 6mm Jackoboard followed by ufh mat, 5mm self levelling, adhesive and tiles which above the Caberdeck will give me about 26/28mm build up. My 2 questions are, Do I lay a thin bed of adhesive and screw down the Jackoboard, or just screw it down ? The shower tray is only about 26mm high so this will need to come up to not risk it being below the tiles. I'm planning on bedding it onto some tile adhesive rather than csand and cement as this seems the recommendation in other posts, do I use the thickness of the adhesive to gain me an extra 5 or 6 mm in height or do I continue the Jackoboard across the whole floor and then bed the tray onto adhesive ontop of the Jackoboard ? Thanks

I was looking at a 32mm with a wall thickness of around 3mm so that I end up with a bore as close to the internal of a 28mm copper pipe as possible.

Thanks @Nick Laslett that was where I saw Nicks comment, I'm trying to find a recommendation for a make or supplier.

I've got to come up through an adjacent shed and then through my posi joists, so I'm thinking Pex-al-pex to be able to form the bends and save any reductions in bore that fittings would cause, I'd also like to run it in from a coil not to have any joints in the ceiling.

I've found a route to get a feed and return into my barn conversion for an ASHP and have been advised to use Pex Al Pex for the bending memory of it, but I'm after some recommendations for which makes to look for, I'm not finding too many with Google searches and the local merchants over here only have PEXb-AL-PERT. I'm also thinking of using 16mm Pex-Al-Pex for my ufh as I'm sure I read somewhere in a thread that @Nickfromwales recommended this over Pex-Al-Pert.

I got time to have another quick play last night. I've checked the numbers in both Loopcad and Jeremy's spreadsheet, both seem good to me and as far as I can see. I've inputted custom figures for the loopcad u-values. Now looking at it I'm wondering if the w/m² shown in each room in Loopcad is what it calculates it is needing as it seems to stay the same whatever I do with the input temp or pipe spacings, with plus figure below it when I increase the input. So am I getting conflicting requirements from the spreadsheet and Loopcad ?

I've just had a very quick look at loopcad, my flow temp was set at 35⁰, I've dropped that down to 32⁰ which has in turn dropped the w/m² down to 23 ish, according to Jeremy's spreadsheet if I work it out correctly by dividing my coldest outside vs inside temp total heat loss for my projected coldest day by my total area, I get around 45-50w/m². If this is the correct way to work out my requirement the how do I get this figure upwards ? Loopcad is saying that I only need more heat in my w/c, yet none of my floors hit 46-50w/m². Can I only up the flow temp or am I looking at it all wrongly ? Thanks

So to do this do I take the, total heat loss power for a 30⁰ difference between room and outside air temp and divide it by the floor area, then design the loops for this w/m² ? My outside temp will very rarely go below 0. Thanks

That's why I want to look at designing the layout myself. I've gone for 150mm centres in the main rooms and 100mm I the W/C and hallway, as the hall has the stair opening plus a vaulted opening to the 1st floor, and a 3.7m x 3.6m glass surrounded front door. There's a set of 3m bi-folds in the kitchen that I tried to get a 100mm loop infront of but the layout didn't work. I've gone for 150mm as I've got 150mm insulation below the current 65mm screed and intent to put the ufh in a 45mm screed above that again. So the pipes will be just above the half way mark of a 110mm screed.

Ll have a look at Warmup. I've contacted Wunda as recommended on here, they seem friendly but they've quoted for 10 loops, which seems a lot and without paying a deposit they won't tell me even a rough layout of how they've spanned the loops.

Hi all, I've been playing around with loopcad trying to get a design that fits in my space and is as equal as possible. I started trying to use spiral counterflows but I can't get these to fit very well. In practice I'll take some of the feeds to the kitchen through the wall and extend others to cover the space left by moving these, but I can't work out how to do this without splitting the room up and can only do this in the opposite direction to the way the circuits fit. What do you think of this design ? It's my 5th attempt so far ... Thanks

But is this the same if you notch both the floor and the bottom of the tray in opposite dirwctions as mentioned ? I thought your bed was ½ of your notch if you only put adhesive on one of the components.

I'm going to screed where my shower tray is going tomorrow. I'll eventually fit the tray with tile adhesive as mentioned, it's a stone resin tray. A 10mm notched trowel was mentioned earlier, is this the recommended notch depth ? If not what do people recommend? Also if I notch to both the floor and tray with a 10mm, what depth would I expect the bed to settle to once the tray is down ? I'm asking so that I know what level to finish my screed at to get the tray at the correct height when installed. Thanks

Does wind chill not affect the performance ? If an ashp was facing south in a sheltered location on a sunny winters day with a chilly easterly wind would it not perform better than if it was in a shaded spot with the wind blowing straight at it ?

I got the weather data from the local met office when I had to get the u-value calculations done for my bco. I'm in sunny Jersey ☀️ although the ashp would face east with nothing between it and a good easterly blowing in from France. I'll ready through those papers later when I can see them on a bigger screen. Thank you.

So I'd be looking at needing a 4kw, or the nearest above that ashp if my calls attached are correct?

I'm still to get an air test, not cheap and I'm not air tight yet. I've filled in Jeremy's heat loss calculator, to try and get an idea of ashp and ufh sizing. Firstly I'm not 100 % sure which figures I should be using fromt eh calculator to work these things out as there's Total heat loss, Inside vs outside heat loss, Total daily min and average, I had someone round to look at giving me a price for them to supply and fit, and also which would be the best position for a unit and route for pipework into the house. The guy did a rough calc on his phone of 40w/m² for ufh multiplied by 90 for the m² footprint of the building, saying I then needed 3.6kw ashp capacity, He then said as I have no heating on the 1st floor, only power points if I did want to put panel heaters in the future, I'd need to double the capacity of the heat pump. Is his theory correct that I'd need to double up having no upstairs heating, and which figure on the calc do I use ? Thanks

Thanks, I'll try and get some to try.

It's timber sill boards on to marine ply, I've got some low foam adhesive left from other tasks but don't mind using a adhesive of that would work better. The timber boards have a slight cup in them so will need a little weight until whatever I use grips them. Do you have a recommendation for an adhesive ? , no more nails, pink grip ,sikaflex ?? Thanks

@Russell griffiths Thank you, i seem to over think everything and you've just given me the simplist most obvious answer that I never thought of. The window boards / internal sill boards are to be fixed down to some solidly fixed marine ply, the underside will hopefully never be seen again so as you've suggested, I'll give them a coat of paint on the underside which the adhesive will stick to nicely. Thank you.

I've got to fit some timber window boards that I've made, the plasterer wants them fully sealed and in before he skims. I've read on here about gluing them down instead of screwing but can't find the thread now. My question is.. is glueing a good method ? I was thinking something like sikaflex or no more nails with a couple of weights on them for a few days. Also if they're oiled both sides to seal them from the moisture when skimming, will sikaflex, or any other glue adhere to the oiled surface at all?

I had a look at the ones you recommended and searched for others too. The ones that I linked to, that are already fitted to my windows are recessed into the frame so I need to find something either the same dimension, or something very similar to cover the recess but also fit int the recess of the head of my window box.