Leaderboard

As you may know we finally got our water connected on Wednesday and our superstar heating installer was on site waiting to get it into the house along with the gas and power. By 7.30 Wedensday evening they had brought the gas and water into the plant room plus a temp power supply and the boiler was fired up and UFH commissioned. Happy to say all working well and now doing the gradual daily crank up. This is UFH in the MBC slab so heart in mouth as no-one can be sure until it kicked into life. MBC laid the pipe for us we didnt use their pipe we used Robbens as they were supplying all our manifolds for UFH and the MVHR system. I’m now getting complaints from the various trades......this house is far too hot, need the windows open never mind its minus outside.......etc ..... LOL. I’m thrilled to bits with the tongue in cheek builders complaints ( they have toiled in very cold temps for me up to now), means we will have a very warm house to live in. May even come near my ambition of covering our heating costs from our OAP winter fuel allowance (yes we are old enough to qualify!). Very happy, I’m going to pop a christmas tree up in there tomorrow so when my men come in on Monday it will be jolly and seasonal and warm. Might even leave them some mince pies under the tree.

Not sure how thick the slab is, so I'll assume 100mm - if it's different it's easy enough to change the thickness and recalculate. From the bottom up: 100mm thick concrete with a λ of ~1.5 W/m.K gives an R value of 0.1m * 1.5 W/m.K = 0.6667 m².K/W 90mm thick PIR foam with a λ of 0.023 W/m.K gives an R value of 0.09m * 0.023 W/m.K = 3.913 m².K/W 20mm UFH boards, λ unknown, so assume same as EPS 200, 0.034 W/m.K gives an R value of 0.02m * 0.034 W/m.K = 0.5882 m².K/W Assume 4mm foam underlay with a λ of 0.034 W/m.K gives an R value of 0.004m * 0.034 W/m.K = 0.1176 m².K/W 6mm ply with a λ of 0.15 W/m.K gives an R value of 0.006m * 0.15 W/m.K = 0.05333 m².K/W 16mm bamboo with a λ of 0.15 W/m.K gives an R value of 0.016m *0.15 W/m.K = 0.1067 m².K/W Adding all the R values above gives: 0.6667 + 3.913 + 0.5882 + 0.1176 + 0.05333 + 0.1067 = 5.4455 m².K/W Taking the inverse of the R value gives the U value: 1 / 5.4455 m².K/W = 0.1836 W/m².K For bonding foam together, then any low expansion gun foam will work well. My personal preference is the Soudal stuff, but there's very little to choose between any of the low expansion foams.

B&Q. 6mm ply or MDF. Free sawing service. If you do it and provide a Youtube video of B&Q sawing up your 40mm x 25mm tiles, or even 48 x 25mm strips, I'll Paypal you beer to half the cost of the 8x4 sheet of ply. *Please don't let there be a minimum size on the B&Q sawing service* F

I cannot believe your going through with this ? Just mark out on the walls and get sticking !!!

+1

That house would look right, with a little door in that gable end to give access to the light from the loft space

It's to attach the freezer door to the kitchen unit door it's hidden (or integrated) behind. Usually white plastic sliders with self adhesive backing. Without a box unit to house it I'd expect it would look ugly and unfinished as although perfectly workable as a freezer. Oh it might not have a door handle though.

id be more worried about the spacers you are going to have to make

Top one will give more even temperature. Bottom one might give a slight temperature gradient from one end of the room to the other.

The needles will fall off if it is too hot

TBH, I've stopped using it for anything except permanent threaded (iron) joints now, as Jet Blue is far easier to use on compression joints, as it can be undone more easily. The liquid PTFE stuff works very well (but is a PITA to get out of the bottle) and if you want to take the joint apart you need to warm it up a bit, which makes the sealant go soft. Now I use a mix of PTFE tape on any threaded plastic fitting (there are a few of those in the water treatment system, on filters mainly), liquid PTFE on any threaded metal fitting that I don't think I'll need to take apart again, and Jet Blue on all other metal fittings.

My local B&Q is 8 cuts from memory and they’ve never enforced beyond that with me. I guess they have to have a policy in place to stop abusers of the service (and dodgy looking, limp armed welsh plumbers )