Thanks Phill thats a great tip, at this time of year I could leave the hulls outside from 9am in the sun, take it inside really warm at 12pm, finish the glass work at 3pm and let it all cool down.
That also makes sense in winter for me to heat the piece being worked on from the inside then glass it.
I'd love to find sheets of poly shaped the same as corrugated iron, that I could put on the roof of the shed in winter. That would absorb the winter sun, heat up the shed during the day and slow down heat release at night.
regards