Spa Fitter
Royal Spa Emperor II Replacement Cover
The Royal Spa Emperor II takes the AIRCAP 1™ X-Large — a foam-free replacement hot tub cover for square spas 92"–94". The Emperor II's cabinet measures 94" x 94", inside the X-Large's range. The cover weighs 35–40 lb for life, costs $1,195, is engineered to comply with ASTM F1346-23, and carries a 3-year limited warranty.
| Spa cabinet | 94" x 94" |
|---|---|
| AIRCAP 1™ size | X-Large fits 92"–94" |
| Cover weight | 35–40 lb — constant for life |
| Price | $1,195, free US shipping |
| Skirt | Ziptech™ modular, three lengths included |
| Safety | Engineered to comply with ASTM F1346-23 |
| Warranty | 3-year limited warranty |
Why the X-Large fits the Emperor II
The AIRCAP 1™ comes in six sizes covering square spas from 77" to 94". Each size is built to overhang its band slightly — that is how a spa cover is meant to sit — so the X-Large, which fits cabinets 92"–94", covers the Emperor II's 94" x 94" shell with the right overhang.
At 94" the Emperor II is at the top of the X-Large's 92"–94" range — the largest cabinet this size covers. It is also the largest square cover we make. Within Royal Spa, the Emperor II shares that 94" x 94" cabinet with Emperor, King, King Ultra and Sultan — same footprint, same cover. The 6 Royal Spa models we fit sit on 2 footprints, and the Emperor II is on the largest of them; together they span 2 of the six AIRCAP 1 sizes.
Cabinet dimensions can change between model years. Before ordering, measure your Emperor II at its widest point across the top, in both directions, including any acrylic lip that overhangs the cabinet — the SureFit™ guide walks through it in two measurements. If a figure you have found elsewhere is larger than ours, an overhanging lip is the usual reason. If your spa measures between two sizes, round up.
Every spa in our catalogue that measures 94" x 94" is on one page: hot tubs that take a 94" × 94" cover — the same AIRCAP 1™ X-Large, at the same price.
How the AIRCAP 1™ is built
Instead of a rigid foam core wrapped in vinyl, the AIRCAP 1™ uses welded drop-stitch construction: a sealed air chamber with no foam to absorb water, so it does not become the waterlogged two-person lift that ends most foam covers. More on how it insulates, how it holds up, and why it is foam-free — or estimate what your current foam cover weighs.
Every Royal Spa model we fit
| Model | Cabinet | AIRCAP 1™ |
|---|---|---|
| Series 1000 (S-1000) | 78.5" x 78.5" | XX-Small |
| Emperor | 94" x 94" | X-Large same cover as the Emperor II |
| Emperor II (this page) | 94" x 94" | X-Large |
| King | 94" x 94" | X-Large same cover as the Emperor II |
| King Ultra | 94" x 94" | X-Large same cover as the Emperor II |
| Sultan | 94" x 94" | X-Large same cover as the Emperor II |
Royal Spa Emperor II cover: common questions
What size hot tub cover fits the Royal Spa Emperor II?
The Royal Spa Emperor II takes the AIRCAP 1 X-Large, which fits square hot tubs measuring 92"–94" across. The Emperor II's cabinet measures 94" x 94", inside that band. Measure your spa side to side across the top of the cabinet to confirm before ordering.
Will the AIRCAP 1 fit a Royal Spa Emperor II?
Yes — the Emperor II's 94" x 94" square cabinet falls in the AIRCAP 1 X-Large's 92"–94" range, and the Ziptech modular skirt system ships with three skirt lengths so the drop over the cabinet adjusts without a custom order. Cabinet sizes can change between model years, so confirm with two quick measurements.
How much does a replacement cover for the Royal Spa Emperor II cost?
The AIRCAP 1 costs $1,195 in every size, including the pump, three Ziptech skirt lengths, and tie-down straps, with free US shipping and 30-day returns. Unlike a foam cover it has no foam core to waterlog, so it stays at its original 35–40 lb weight for life.
How heavy is a replacement cover for the Royal Spa Emperor II?
The AIRCAP 1 X-Large weighs 35–40 lb and keeps that weight permanently — its sealed drop-stitch air core cannot absorb water. A foam cover starts at 40–75 lb and gains weight as the foam saturates.
Not a Emperor II?
The Spa Fitter matches the current models of every major brand to the right AIRCAP 1™ — or measure any square spa with SureFit™.