Many people leave their wooden decks or fences unprotected until greying becomes quite obvious but the sun and other weather conditions start to work right away – a lot of irreversible damage is done to your wooden structure within the first year. The best time to apply a sealer / stain is as soon as construction is complete. Only then can you ensure that damage from the sun and other weather conditions is minimized. Every 2nd or 3rd season the deck or fence should be inspected by a professional to evaluate the condition of the sealer and determine if resealing is necessary. Keep in mind that horizontal surfaces like deck tops, will wear down faster than vertical surfaces like fencing. High traffic areas are especially prone to accelerated wearing of protective sealers.