Thanks for the responses guys...

I considered using insulation when building the Zerba Tree but decided
against it in the end. It would delay warming for sure, but would also
slow the cooling process, removing a key benefit of having the scope
permanently set up in "near ambient" conditions.

I like the greenhouse vent idea - nice and simple. I'll install a
couple this weekend. Be warned; if it works then the remainder of the
summer will be unseasonably cool :-)

Cheers
Beats

Steve Taylor wrote:
Martin Brown wrote:

The one I found most effective was to use the foil backed polystyrene
on the inside surfaces of sun facing parts of the structure S & W and
roof. This slows down ingress of heat significantly.

"Celotex" very expensive in B+Q, but similar from Travis Perkins.
Polystyrene is horrible, it might not burn these days, but it would drip
molten plastic in a fire. Celotex doesn't.



Some mechanism to let the hottest air out of the top without letting
dust or rain in might be worth considering too. I don't have this.

Greenhouse vent ? The wax powered piston jobs.

Steve