I would use 50mm.(my covers are 50mm, 4 years old and still going strong)
And I would paint with a solvent paint like hammerite as it will do much to protect surfaces. (I used water based which lasts but gives no protection to knocks. Masonry paint tends to peel from stressed areas- at least I find it does.
Thanks... some good points.
But
as expected some replies that add nothing to the request for practical advice
, and thanks to those who PM'd me with helpful links.
Have a surplus of 25 WRC, WBC brood boxes still flat packed... probably been in storage for 15 years.
Instead of using up the Paynes and Masie polly nucs to overwinter this years new bees, and buying even more in,I gave some thought to utilising the WBC brood boxes.
Obviously the thermal coefficient value of 12mm WRC is going to be low, and I can lay my paws on loads of offcuts of 50mm Cellotex/Kingspan.. for free.
Bespoke floors with a bit of open mesh and roofs are simple to make... and have acquired another scrapped aluminum caravan to cut up for roofs.
A packaging plastic tape kit from Mr Wong is about £50 on ebay, but the clips are mild steel, probably OK if painted?.... plastic extrusion for corners.. even flight case thick stuff works out about £4 per box.
Have 10 liters of garish purple gloss hammerite type paint I was going to paint the garage doors with...now replaced with new roller type electric( even though there is no space for a car in there!!)
£15 - £16 per box finished.. even if I had to buy in 50mm Kingspan from Travis Perkins?
What is the best type of adhesive to use.... would stick the 50mm cover to the WRC.
Only annoying thing is the standard type National roof I already use do not fit, and all the BHS polly hive roofs I have are in use... but would fit.. just!
Any more thoughts???