Hi, I'm building a shed, from scratch, from pallets (well mostly). I have the base, and a frame all the way round made from radiator pallets which are quite tall with little wood on the them (great for the frame). I dismantled a load of other pallets for their wood, with the intention of routing the edges so that when I clad the outside of the frame, they'd butt together nicely. I canned that idea as it would have taken me yonks to do. So I've clad the outside of the walls with the wood, just putting the planks butted up against each other normally. as you'd expect, as I did, there will be small gaps here and there, and I reckon nowhere will it be waterproof. Is there any waterproof render I can buy that will both seal the wood, but also be thick enough to cover those gaps? Or, am I better off with creosote, and fill the gaps with an outdoor sealant? Cheers