Deck skirting can be an attractive feature that can be added to any low-level deck. You can use boards to construct a wall around the bottom of your deck. Another option is to use wood or vinyl lattice material. Make sure you leave gaps for ventilation to prevent mold from growing under the deck. You should install a door for access to under the deck. This area can be used for storage. You shouldn't anchor the skirt to the ground because frost heave will eventually damage the skirt. Constructing a deck skirt will require a lot of additional material depending on the height of the deck. Typically, lattice is sold in 4' x 8' sheets. There is also considerable added labor involved.
Here is a nice example of how you can install skirting, fascia and an access door under your deck.
Install a nailer board between support posts to attach the bottom side of the skirting or install 2x4 vertical framing flush on the outside of the frame.
Use a piece of scrap material to space your skirt boards. In this case we used a 1/2" thick piece of base trim. Next, fasten each skirt board to the top and bottom of the skirt frame. Keep the bottom of the skirt at least 1" above the ground.
Start each section using a level. Use the level every 4-5 boards to make sure the boards are still plumb.
Install vertical 2x4 framing to create the access door opening.
Fasten the vertical 2x4 framing to the deck frame using screws. This technique could also be used to support all the skirt framing if you don't have any available support posts to attach to.
Build an access door using a Z brace. Make sure the angle brace starts at the bottom hinge and ends at the latch. Cut a 45 degree bevel at the end of the trim under the hinges to allow the door to swing, as shown in the first slide.
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