Super_Paulie

I was going to do something very similar. Our bathroom is tiny, i guess floor space once the bog, bath etc is taken away is around 2m x 2m. I was going to just extend the the return from the towel rad to i guess loop round the area before it heads out the door. Might be ill-advised but it seemed that a return over a small area wouldnt cause any real issues. I was also debating doing the same in the porch (1.8x1.8) as i dont want to run my UFH through there but simply to keep the air dry due to wet coats etc being in there. Happy to be told otherwise!

Fair enough, I've got a shed ton of 50mm left anyways. Thanks my good man, might even have heating in time for winter, who knows!

Illbruck 330 ordered and i have all the insulation in and to be foamed. Filled the "batten void" with 50mm PIR with the 120mm resting on the battens. Would i be right in thinking that i should create an insulated barrier from where the pug/biscuit mix goes to the end of the joist run to avoid it losing heat into the wall? like this crudely drawn image (without biscuit mix shown)

Interesting, id read otherwise. I'll do more research on that. If I have the boiler 3a and the wiring centre 5a from the same FCU, how would I protect both from a single fuse?

I was under the impression flex is frowned upon over distance? We are looking at 15m maybe from boiler to wiring centre. So ignore the fact I wouldn't get DHW if the wiring centre needs isolating for whatever reason? Probably a situation that would never occur to be fair.

Cheers Tony. But that would mean I have no "local" isolation at the boiler? Guess it doesn't really matter but I was going to go from solid core to flex at loft level so may as well put the "local" isolation in instead of just a junction box. If I don't have isolation down before the wiring centre but after the FCU then I'd have no means to knock that off and keep the combi providing DHW, but how often that situation will come up is anyone's guess. Boiler on its own circuit could happen, the wiring centre is almost at the consumer unit anyways.

i agree, was just drawing that up. Hopefully if we are off the mark someone will advise but im hoping to test this out at some point this afternoon.

so i guess.... thats means i wouldnt need to run the LS though the isolator at all as it is never live.

its a Baxi 830. To keep it simple im using the "240v control connection" instead of anything OpenTherm as i dont think i need that. Attached picture i found online but mine is the same. The Heatmiser LS (live supply) and the LR (live return) are volt free, so connecting those in place of this yellow loop will call for heat, i believe.

Cheers Dave. So like this? (earths omitted for clarity) I assume i wouldnt need to isolate the live return to the Heatmiser as it the live supply is clipped at the 3 pole. Quick couple of points if i may. Without a second isolator down at the wiring centre i wouldnt be able to isolate it without killing the juice to the boiler, so if i had an issue down there it would also cut off my potential for hot water only. Should i add in that secondary isolator or am i just being overly cautious in regards to future issues? The heatmiser needs fused down to 5a and the boiler 3a, what fuse should i be looking at in the FCU? Cheers fella. Im the type of bloke who needs to draw it all out in advance. Makes for slow work but thats all my brain will accept.

If my Baxi needs protecting with a 3a and my Heatmiser a 5a, how can I run these from the same spurred FCU? Davinci level drawing attached.

Apologies, phone keeps autocorrecting to FSU for reasons unknown.

I've already got 2 FCUs from the ring final, one at each location. But it dawned on me that when you knock the boiler off it should be knocking the wiring centre/gubbins off at the same time. Or not?

I'm sure you knowledgeable lot can answer this in a jiffy, I can't seem to find the answer online. Boiler in the loft, wiring centre (and UFH gubbins) on the ground floor. Should both of these be powered from the same FSU? Just means they are a long way away from each other in terms of local isolation...

Cheers gents, I went ahead and did it. If nothing else it tidied it all up and will protect the foam from getting banged up 👍

For the uneducated amongst us, is there any benefit in completely surrounding the foam lagging around hot water pipes with aluminium tape? Or will the foil just conduct heat out of the pipe/lagging? Just insulating the return pipes that run through my loft to try to minimise the heat loss.

Just to finish this whole drama and say cheers to you guys for the help, the tank is in and pressurised. Although I have a daft tap on the top (I reversed the tank) going into a compression-solder-1/2 bush it holds just fine. No idea what the problem was but I have no doubt that this will work out ok. The tank is wall mounted, even though I could have had a free standing one, the Cordivari was the exact width I needed to go in this location without jutting out and meant my pipe work was a lot simpler. I've tested the diverter valve and it works, just need to rig it to the rad 2 port in the room below. So I can move on finally, cheers guys and thanks. 👍

Any genius suggestions on how I attach? The top layer is resting on the battens obviously but the lower board will have nothing underneath it. Nails angled downwards slightly? I don't have the room underneath to get a driver in to attach any supports.

💸 another week another dollar!

Understood captain 👍 If I have any left over fibreglass should I whack that in our just bite the bullet and order in more 40mm PIR?

I was going to go with expanding foam all around the perimeter? Seems to be the easiest way and what I've done in the past.

Yeah probably not really a concern seeing as it's the ground floor. I was going for the more insulation the better, seems to make sense if you can get either of the types for next to nowt/free.

Evening gents. The build-up for my suspended floor is the same as the attached image. PIR 120mm but less in places where it was necessary. My question is, the area where the support battens are, that's a void there. Would there be any benefit in running a membrane under the joists and laying in a 50mm fibreglass roll in that void area? I could also potentially friction fit/foam in another pir board of 50mm. Was just wondering if a PIR/fibreglass roll combo would provide any additional benefits. I'm aware you need twice as much fibreglass to be comparable to PIR but a mix of materials might provide untold benefits?

Could use a motorised valve connected to a leaky hose, but hardwired to a plug. Then the plug connected to something like a Tapo. "hey Google, water the garden" The tapo app lets you schedule timings etc. That's something I've been thinking of doing, but haven't looked at it in detail so far.

Just a mock up with old bits of pipe but I think it'll go in just fine. Been a long road, but fingers crossed, never even thought about the diverter valve before so hopefully that'll be dandy once rigged up to the rad zone valve.