Do you need drainage under decking?

Another question that might be asked is, "Does decking require drainage?"

Standing water can cause wood to deteriorate and warp, as well as encourage the growth of rot or fungus. It can also cause slippage. Drainage problems should be addressed before you install the decking board. You may need to remove decking boards in order to divert drainage from an elevated deck.

Do you need to seal your deck's underside? You don't need to seal the deck's underside for protection against the elements. This is especially true if your deck is made from pressure-treated wood.

Also, what can I place under my deck to stop water from getting in?

Deck Membranes or Downspouts: The most common method of waterproofing below decks is to place plastic membranes in joist spaces to create troughs. The Trex RainEscape deck waterproofing system, shown below, is an example of a membrane-and-downspout system.

What material is best to use under a deck?

Inorganic mulch, such as gravel, crushed rock, or river rocks, is recommended if the area below your deck or stairs is likely to collect water or become moist. Gravel is an excellent material to use under outdoor structures because it allows water drainage and doesn't decay.