A patio furniture cover has one job and two ways to fail. It can let water in, or it can trap water underneath. The second failure is the more common one and the more damaging — a cover that seals completely against a damp cushion produces mildew faster than leaving the furniture uncovered would.
Good covers manage both: a coated outer layer that sheds rain, and vents plus a breathable underside that let trapped moisture escape. Everything else — straps, elastic, colour, zippers — is about keeping that system in place through wind.
What the specifications mean
| Specification | Light duty | Mid duty | Heavy duty | What it changes |
|---|---|---|---|---|
| Fabric weight (denier) | 300D | 420–600D | 600–900D or vinyl-backed | Tear resistance and how it handles wind |
| Coating | Light PU or PVC | PU or PVC laminate | Heavy laminate, often welded seams | Water resistance and UV life |
| Water performance | Water resistant | Waterproof panels, stitched seams | Waterproof with taped or welded seams | Stitched seams leak in driving rain |
| Air vents | None or one | Two mesh vents | Two to four vents, often screened | Prevents condensation and lets wind pass |
| Securing | Drawcord hem | Drawcord plus buckle straps | Drawcord, straps and click-close buckles | Whether it stays on in a storm |
| Realistic life | 1–2 seasons | 3–4 seasons | 5+ seasons | Cost per season is usually lowest at mid to heavy |
| Best for | Summer dust, mild climates | Most US yards, three-season use | Snow load, coastal wind, year-round cover |
Two spec lines are worth checking specifically. Seam construction — taped or welded beats stitched, because every needle hole in a stitched seam is a small leak. And venting — a cover with no vents will balloon in wind and sweat underneath in sun, and it is the single most common reason a cover fails in year one.
Measure in five steps
- Measure width at the widest point, including armrests, and depth front to back including any footrest or overhang.
- Measure height from the ground to the highest point of the piece — usually the back of the tallest chair or the peak of a stacked set.
- Add 2 to 4 inches to width and depth. A cover pulled drum-tight tears at the corners in the first windstorm. This is the step most people skip.
- Subtract 2 to 3 inches from height so the hem sits above ground level. A cover that touches wet grass or a wet patio wicks water upward for days.
- Decide what stays outside. Cover a table with the umbrella removed and the chairs pushed in, or cover the whole set as one — the two need very different sizes. Umbrellas get their own sleeve cover; see patio umbrellas.
Fitting it so it lasts
Slope the top. Water must run off, not pool. If the covered shape is flat, put something under the centre — a folded chair, a bucket, a purpose-made support pole — to create a peak. A pool of water on a flat cover weighs enough to stretch the fabric permanently and, in a freeze, to split it.
Cover dry furniture only. Wipe surfaces down, let cushions dry fully and bring fabric cushions indoors or into a deck box if you can — see outdoor cushions and pillows and outdoor storage and housing. Tighten every strap and drawcord, then check the cover after the first windy night and retighten.
Give it a mid-season check. Lift a corner every few weeks, look for condensation and for anything nesting underneath. Mice and insects both find covered furniture attractive; a quick look costs nothing. Full range in patio furniture covers, grill-specific covers in grill covers, and the seasonal checklist in winterize your yard.
Common questions
Waterproof or water resistant?
Waterproof for anything left out through a wet winter. Water resistant is fine for summer dust and light rain in a dry climate. The difference in practice is the seam treatment, not just the coating.
Should I cover furniture all summer?
Only between uses if you get heavy pollen, sap from overhanging trees, or storms. A cover left on damp furniture through humid weeks is worse than no cover — set is best covered dry and uncovered often.
How do I stop a cover blowing off?
Use the straps under the piece, not just around it, and size the cover with the small allowance above rather than oversizing it. A loose oversize cover acts like a sail. Weighted bags at the corners help on exposed sites.
Can I wash a patio cover?
Hose it and wipe with mild soap. Do not machine wash or pressure wash — both strip the coating that makes it waterproof. Air dry fully before folding, or it will mildew in storage.
What about snow?
Brush snow off rather than letting it accumulate. Wet snow is heavy, and the load will stretch or tear a cover and can bend lightweight furniture underneath it. Heavy-duty covers with a peaked centre shed it best.
Free US shipping on every order.