Hi, my father has made two Swift boxes for me, in preparation for this season. I wondered if someone could help me understand what type of product I could paint on the wood to make it waterproof and preserve the wood which would not be poisonous to the Swifts? Thanks in advance. Tina
Hi Tina, I had a bit of a look online and found THIS which is safe to birds/wildlife and says it is approved by rspb. I think brands like water-based "Cuprinol" are also ok, but definitely avoid products like creosote.