Nickfromwales

Big issue is how much DHW is drawn off and when though? Would suggest the TS is serviced on demand if the extra independent heating zone is added plus DHW is required 'on tap'.

? Don't you mean that it does not control the boiler directly? With a TS which is servicing DHW too ( assumed ) then the cylinder stat controls the boiler and primary pump and he timeclock decides when. Therefore you would need a separate zone valve tee'd off the heating output from the TS which can command the boiler ( override the timeclock ) independently. That wouldn't be so problematic if you only want to use the annex in parallel with the current 'heating on' times? An idea of how you time heating and hot water ( DHW ) would help

When the Zone valve brown is energised the motor creeps to the open position ( 8-10 seconds will elapse ). When the valve head reaches the 100% open position, it presses against a micro-switch inside the zone valve which is over the orange and grey pair of cables ( 5-wire ) eg to switch on the boiler and pump ONLY when the valve has fully opened. You do not need the switching pair, and you could have just fitted the 3-wire version. Not an issue, but just to help you understand what they do

OK. Green / Yellow = Earth Blue = Neutral Brown = Live to motor ( which opens the valve ) Orange = Common of call for heat switch Grey = Switched live out of call for heat switch Connect the blue and G/Y to the same terminals shared by the heating system supply. Split the 230v feed to actuator / zone 3 output from the Heatmiser and connect that to the brown. That will get the motorised valve to open and close with the actuator. That should be all you need?

Hi Keith, and welcome. Isotex in the title so have you made your mind up on ICF? Also, one bed....does that mean single story or 2 storey? Type of roof etc? Info, and more info

Beware the regs / good practices on the lower temp ‘dead legs’. Ideally you should be putting lower temp TMV’s at the point of discharge rather than point of origin. With 50oC set point at source, is there really any reason to lower the second group? At that temp you have little to zero risk of scalding and I assume your outlets will all be mixers anyway? Seems a bit OTT tbh.

We fitted sprinklers in one large job, but tbh I could have got away with not fitting them. As the egress routes were quite convoluted it was mutually agreed that they were a good idea. BCO was happy to see them go in, but indicated that they were not mandatory in that specific instance. Confusion reigns still. Piss-takers still take advantage. Loopholes offer such opportunities

Not too shabby Bruce. 😎👍

Cold feeds for outside taps should be off the rising main, before the domestic stopcock, rather than fed from the internal plumbing setup As for the rest of the runs, stick to your guns and don’t worry about the number of runs. It’s a far better setup than series plumbing, and bums do twitch when the numbers start getting to what some would see as ‘silly’. Are you doing hot returns to basins / sinks?

https://www.walesonline.co.uk/news/wales-news/thousands-new-homes-wont-sprinklers-13684910

£6k installation fee. 😂

Then I’d say the mat may be omitted over that then. Is the plywood top layer glued and screwed well?

Were all the layers bonded to the sips / between layers? Eg no movement when you walk on the floor?

Ah, yes. Apologies. In bathroom mode atm. Still disagree with trying to glue ANYTHING into a cut hole in PB. It’s only the paper face, and the paper face alone that you can get any tiny bit of purchase with, so no, and no again. If it’s a true stud wall and there is a cavity, then the collapsable “toggle” fixings reign supreme.

Nothing sticks to cut gypsum in the core of PB It’s like trying to glue something to talcum powder. No sale.