I'm building a new timber frame build. Our contractors are now filling the frame with 100mm kingspan insulation, but a lot of the inserts are loose and there are many gaps and holes. Many of them are tight and I'm told it's the average that counts. Am I being had?
You are not mad!
They are ripping you off!
Heat always moves to cold - by the easy route.
Your heat will merely go round the pieces of insulation.
Insist that you want what you are paying for:
That is, the job being done properly, with the insulation being a proper tight fit.
Refuse to pay them if the job is done badly.
But, keep in mind your personal safety, they may turn nasty.
Make sure you know where they live, so you can get in touch later if you need to.