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I had new wooden decking installed on my balcony. The guy that did the job says it doesn't need stain because the wood is already treated: http://www.diy.com/departments/premium-brown-softwood-deck-board-t28mm-w144mm-l3600mm/945944_BQ.prd
He said to sand and stain it in two years time, but I was wondering if I stain it now maybe it will last more than two years? I live in London so, as you probably know, it rains A LOT. Wood is a very poor choice, but I can't change it because of the rules in my apartment lease.