We are knee deep in an extensive extension and renovation project. Most things are being carried out by a building company but we didn't like their suppliers window sample so removed the windows from the contract and sourced ourselves. We've had no end of issues relating to the windows and doors both prior to and as we are now, mid installation. All the prior issues aside ,we now find ourselves stuck between a rock and a hard place and wonder if anyone might have some knowledge which will help.
The house is a mix of new cavity walls, old cavity walls and solid walls. The builders removed all the windows and almost all of the existing areas have been re sized plus a good number of new openings for windows created. The builders installed cavity closers in the new parts of the house but no DPC. Building control are saying all the windows need a DPC. Most windows have now been fitted with a Fensa registered installer, one of their installers admitted he should have refused to fit them when he arrived and there was no DPC. Builders are saying it's the responsibility of the window supplier, window supplier are saying it should be the builder.
Private building control consultant is pointing the finger at the window installers but i'm not 100% convinced of their impartiality. I don't understand how it's possible to fit a DPC after a cavity closer is installed which implies to me that it's the builders job. Builder and window supplier are both saying DPC isn't needed but our build won't be signed off without it and regs aside, after a bit of research it really does seem to be sensible to have it in place. Is there anyone with any knowledge on the subject who might be able to point me in the direction of anything in writing I can give to whichever party to confirm it's their responsibility to install the DPC?