AIRCAP 1™ vs SpaCap: Two Generations of the Air Cover

If you're comparing the AIRCAP 1™ against the SpaCap, you've already made the important decision: no more foam. Both covers exist because foam cores absorb water, get heavy, and fail on a 3–5 year clock. Where they differ is how they put air to work — and the difference is generational.

A note before comparing: as of August 2026, spacap.com shows a domain-parking page and we could find no active ordering channel. We've kept this comparison factual and based on SpaCap's published design; if their availability changes, we'll update.

Two constructions, one principle

SpaCap's approach (1980s-era design): a sewn fabric shell — offered in premium outdoor fabrics — containing loose air bladders, from two up to five. No foam anywhere, so nothing to waterlog. But sewn seams and separate bladders mean the cover drapes rather than spans: it follows the water line, can pool rain in low spots, and relies on the bladders staying put and staying inflated individually.

AIRCAP's approach (paddleboard-era design): a single heat-welded, UV-resistant PVC drop-stitch panel. Drop-stitch means thousands of internal threads connect the top and bottom skins, so at pressure the panel becomes rigid — the same reason an inflatable paddleboard can hold a standing adult. One chamber, no seams to wick, a true span across the spa that sheds water, framed by the Ziptech™ modular skirt for a semi-custom fit.

Side by side

SpaCap AIRCAP 1™
Air containment 2–5 loose bladders in a sewn shell Single welded drop-stitch panel
Rigidity Soft — drapes on the water line Rigid when inflated — spans the spa
Rain and snow Can pool in low spots Sheds — no sag to collect it
Foam to waterlog None None
Weight over time Stable Stable — 40–45 lb, day one to year five
Safety standard Not advertised Engineered to comply with ASTM F1346-23
Fit Custom-made, any shape Six sizes, square spas 77″–94″
Price From ~$500 + upgrades (historical) $1,195, three-year warranty
Availability Website offline as of Aug 2026 In production, ships from stock sizes

Where SpaCap genuinely had the edge

Fairness matters: SpaCap's made-to-order model fit any spa — round, octagonal, in-ground. The AIRCAP 1 is engineered for square spas from 77″ to 94″. If your tub isn't square, see our guide to SpaCap alternatives for the options that still fit your shape.

The bottom line

SpaCap proved, over decades, that hot tub owners would happily trade foam for air. The AIRCAP 1™ is what that idea looks like rebuilt with modern materials: welded instead of sewn, one rigid panel instead of loose pillows, a safety standard on the spec sheet, and a three-year warranty behind it. If your spa is square, find your size in the Spa Fitter — it takes about a minute.

Want the full landscape? Our complete guide to hot tub cover alternatives compares all six options.