Hi, 4get. I had one last year there is not a lot to it, they usually check outside walls for cavity insulation, whether you have double glazing or not, loft insulation and what type of central heating boiler you have.
No such thing as failing on HIPs. They check age of installations, wiring/plumbing etc to report to purchaser.....it can all be done online - see link.
It won’t be deal breaker for any potential purchaser... although doubtless in a couple of years you’ll have some jobsworth from the council checking up on people who’ve had a HIP to see if you’ve implemented things to get the house up to maximum efficiency and save the polar bears... or get a fine.
I am sure our 250 year old home would come out with a really low score, yet with it's thick walls and low ceiling its cosy and warm in the winter and cool in the summer and environmentally friendly The whole thing is totally stupid unless you live in a modern home. It's just making a lot of new jobs and some money for estate agents. I don't think prospective buyers take a lot of notice. So don't worry about it.
we are building a new house and had to do a predicted Energy Report. We are a C (77) and B (86)
We have had to fit a renewable energy system for the heating - and chose a ground source heat pump as opposed to solar panels.
Sadly - although this is very very green... we are penalised on an energy efficiency to a C rating as opposed to B as the pump requires electricity to convert the ground heat to central heating (albeit a small amount!)
NHBC admitted that the system is unfair and doesnt take into account eco powered methods fairly.
To obtain an A you bascially have to generate your own power.. using wind and solar!!!!
I think that builders in general think the whole system is ludicrous. Ill thought out and unworkable. Doesn't help the buyer or the seller. I doubt whether anybody gives them any credence and it just costs more money for the seller.