Is there a rule of thumb as to also stain the 'underneath' area of the deck, i.e. the reverse side of the deck bords which would not be exposed to traffic, plus potentially the structural boards ?
Lastly, how long has the deck to age before I can start staining. I heard conflicting opinions (1 year/season vs. 4-8 weeks to trap the PT-moisture after some initial drying).
Deck Location: New Hampshire
Deck Material: Pressure Treated
Age: 1 months
Exposure: Morning-to-early-pm full sun exposure
When to stain new wood varies widely based on the brand of stain. Some stains can be done almost right away and others suggest to wait for 1 year. No need to do the underside. We like the Timber Oil Brand or Armstrong Clark as they can be applied within a month of the deck being built.