stephanh

I am prepping for extension and alterations. The existing building has copper pipe running in the screed to existing rads. and as this must be a 50 year old system, time for update before it all goes wrong! Intending to insulate all existing exterior walls with 50mm PIR (or maybe Knauf) between studwork which will be fixed to 50x25 batten against wall (empty cavity), 18mm OSB covering studs and then 12mm placo. As this creates an area to run pipework through, I intended to drop new pipes down to rads in this fashion. Herewith my dilemma, plastic or copper? I would like to use plastic because of it's simplicity but others have argued against it, preferring copper. I shall revert to copper through the wall to connect to rads, but still have the thing for plastic otherwise. So, what way to go???

thanks for replies - I shall swallow the doubts and full fill

starting extension to bungalow (1970 I believe) - I had expected a 350mm cavity wall with Thermalite inner leaf 100mm celotex PIR 50mm air gap and medium dense outer leaf. Spec now reads as 350mm wide but with a full fill 150 Knauf insulation I feel a little uncomfortable about the full fill aspect, although reading the Knauf description I shouldn't do. Am I being too suspicious about the loss of the air gap?

the previous Matrix was pumped due to the fall being a little difficult, with the present location that would not be an issue and therefore a gravity outlet will be the target. I suppose that having experience of the Matrix then to install same again would be the way to go, just trying to assess if there might be a better option out there.

need to replace old existing septic tank and would like to install best possible TP have used Matrix before (pumped outflow) and found it OK apart from noise of electric stuff - in 6 years had to replace pump 3 times Ok, what are your particular preferences?

only recently found this forum, so ................ have completed 3 self builds and renovated other places, but still struggle along. You would think I would have learnt something along the way, but probably too stupid to do that. Just starting out on a single storey extension and alterations to latest, and likely last, property (getting old). Hopefully I shall last long enough to finish the job.