Sips and stones may break my bones...

"The designer is saying they did not allow for X, Y & Z in the price and so on"

 

What does your contract with them say?  Presumably by the time you got to sending off a deposit the price was fixed?  It would be a strange contract for this sort of thing where they're allowed to come back and arbitrarily add stuff they decided not to include in their quote (unless it's clear that the quote didn't cover everything).

My quote clearly stated what was and what wasn't included. I would go back and check your earlier correspondence/quotes. I did however notice a very different tone in their dealings with me once they had received my deposit. They turned out to be complete $&*£% in the end.  Hopefully you haven't gone with the same outfit as I did.

11 hours ago, oranjeboom said:

They turned out to be complete $&*£% in the end.  Hopefully you haven't gone with the same outfit as I did.

 

Might be worth a quick private message.  If it is them, it might be useful to know now, and to have some idea of what to keep an eye out for.

Well, I got a call from the designer assuring me he wasn't trying to bump the price but had realised there were a couple of issues more complex than at first realised. Now looking at them, I think it's probably fair enough - one being extra beams where we are having one of these sort of windows https://www.keyliteroofwindows.com/roof-windows/vertical-bi-lite at the top of the stairs which are larger than one SIPs panel so will need more support, and an issue where the stone outer wall would have been above the porch SIPs which obviously could not support it without some beams (which I've solved cheaply by a simple change). So in all, I suspect it won't be much of a hike but we shall see. They sent me their plans and asked me to check all the dimensions - so I did the sensible thing and sent them to our  architect to check for me, who spotted a few issues, of which only one I had noticed!  So the plans are back with the SIPs folks with my architects notes for now.    

Edited January 29, 2017 by curlewhouse

Well, the beam and block is all done and foul drains work starts on Monday. Today we've been sorting through stone for a drystone wall.