Deck Skirting Calculator
Our free deck skirting calculator figures out how much material you need to enclose the open sides of a raised deck. Enter your deck's length and width, how many sides you'll skirt, and the skirt height — you'll get the total skirt area in square feet, plus how many vertical boards or lattice panels to buy, with a cutting-waste allowance and an optional access-door opening built in.
Enter your numbers
Exclude the side attached to the house — 3 sides is the most common.
Your results
| Deck perimeter | — |
| Skirted length | — |
| Access-door deduction | — |
| Net skirt area | — |
| Area incl. waste | — |
Ventilation: stop skirting 1–2 in. above the ground and add a vent roughly every 8–10 ft of run. Never fully seal the under-deck area — trapped moisture causes rot.
How to use this calculator
Measure your deck's length and width in feet, then pick how many sides you'll skirt — 3 is typical because the house side is already enclosed. Enter the skirt height from the bottom of the deck frame down to about 1–2 inches above the ground (don't run skirting into the soil).
Choose your material: vertical 1×6 or 1×4 boards cut to 8-foot lengths, or standard 4×8-foot lattice panels. The coverage-per-unit box fills in automatically (8 ft × actual board width, or 32 sq ft per lattice panel), but you can edit it if you use a different board width or panel size. Set the cutting-waste percentage (10% is a safe default) and enter the width of any access door — we'll subtract it so you don't overbuy.
How it works
The math is simple: skirt area = deck perimeter × skirt height. Perimeter is 2 × (length + width), scaled to the number of sides you're skirting. Then we subtract the access-door opening (door width × skirt height) and add your waste percentage. Unit count = area with waste ÷ coverage per board or panel, always rounded up to whole units.
Lattice vs. board skirting: lattice panels (4×8 ft = 32 sq ft each) are cheap, install fast, and breathe on their own, but they hide less and read as more casual. Boards give a solid, finished fence-like look — a 1×6 is 5.5 inches wide when dressed, so an 8-ft board covers about 3.67 sq ft — but solid boards need planned ventilation: leave the 1–2 inch ground gap and install one vent panel roughly every 8–10 ft of run.
Access doors: if the space under your deck holds plumbing, electrical, or storage, frame an opening at least 24–36 inches wide with a hinged or removable panel. Enter its width in feet and the calculator deducts that area before counting boards.
Counts are planning estimates rounded up. Irregular decks, slopes, or stepped skirt lines need a measured skirt length instead of the full perimeter — use the tool with your actual numbers.
Frequently asked questions
What is deck skirting, and why should I add it?
Deck skirting (also called deck skirting panels or under-deck enclosures) covers the open sides of a raised deck from the deck frame down toward the ground. It hides joists, posts and stored items, keeps animals out, and gives the deck a finished look. Boards give a solid fence-like finish; lattice panels cost less and allow airflow.
Should deck skirting touch the ground?
No. Stop the skirting 1 to 2 inches above the soil or hardscape so water cannot wick up into the wood, and add ventilation: one vent panel roughly every 8 to 10 feet of run keeps moisture from building up under the deck, which prevents rot and mold. Never fully seal the under-deck area.
Do I need an access door under my deck?
Yes if the under-deck space is usable for storage or houses plumbing, electrical runs, or shutoffs. Leave a framed opening at least 24 to 36 inches wide with a hinged or removable panel. This calculator subtracts a gate opening of your chosen width from the skirt area so you do not overbuy material.
Board skirting or lattice skirting: which should I choose?
Vertical or horizontal boards look more finished and block sight lines completely, but they need more material and you must plan ventilation openings. Lattice panels are cheaper, faster to install, and breathe on their own, but they hide less and can look dated. In wet climates boards with dedicated vents last longest; in hot humid climates lattice's airflow helps.
How accurate is this estimate?
It is a planning estimate. Skirt area is deck perimeter times skirt height, minus any access-door opening, plus a 10 percent cutting-waste allowance by default. Board and panel counts are rounded up to whole units, so you will not run short. For odd shapes, slopes, or stepped skirts, measure the actual skirted length and use that instead of the full perimeter.