rob dayglo

Hi All, so I am internally fitting out my timberframe house. To meet the SAP requirements the frame has 140mm mineral wool insulation, then the vapour barrier then counterbattens 24mm deep, creating an air gap then standard 12.5mm plasterboard. However I now see that there are alot of self builders filling the air gap between the vapour barrier and plasterboard. So my first thought is to fill it with 12mm PIR board as I have a good price on 25mm roofing batten and the building budget is getting very tight. So the questions are. Is it worth doing? What would be the most cost effective material to use? (I considered SF6 Superfoil but its £5.63m2 compared to 12mm PIR @ £3.70m2 All advice gladly received

thanks

Thanks for all the replies. Sorry if I did not make myself clear. I was specifically referring to plastic fittings and MDPE pipes. My confusion arises when you can buy a plastic fitting for example by Floplast and also a Flopast insert. What im trying to find out is will any plastic insert work with any plastic compression fitting

Hi, I trying to find out if mdpe pipe inserts are universal . Will any mdpe insert work with any manufacturers fitting, for example will a John Guest insert work with flowplast or the other way round. Are they also compatible with brass compression fittings? Thanks in advance