Choosing the Right Pool Reel Width for Your Pool (with Sizing Chart)
A wrong-size reel is the most common reason a perfectly good cover ends up in a heap by the deck. Here's a clear sizing chart and the two pool measurements most people get wrong on the first try.
Pool reels are sold by tube length. The tube needs to be wider than the cover, and the cover needs to be wider than the pool. Sounds simple. The reason this still goes wrong for half of buyers is that "wider than the pool" depends on how you measure the pool — and pools are rarely as wide as people think.
Let's get the measurement right first, then talk about reel sizing.
Measure the pool, the right way
Two measurements matter for sizing a reel:
- Pool width (the dimension the cover and reel span across).
- Pool length (the dimension the cover unrolls along).
Most people measure both at the water line, get a number like "16 by 32," and use those. That's almost right but for one detail: pool covers are sized to extend beyond the water's edge by 1–2 feet on each side, sitting partway up the coping. That means the cover is wider than the pool, which means the reel needs to be wider than the cover, which means the reel needs to be wider than the pool by 2–4 feet total.
The correct way to measure:
- Use a tape measure laid across the pool at its widest point. Note the water-line width.
- Add 24 inches (12 inches per side) for cover overhang. That's the cover width.
- Add another 6–12 inches for reel-end clearance (the cover shouldn't run all the way to the tube edges or it bunches and tears at the end caps). That's the minimum reel tube length.
So a 16-foot wide pool wants a cover that's about 18 feet wide and a reel tube that's about 19 feet long. Most "16-foot pool reels" advertise as 18 or 19-foot tubes for exactly this reason.
The two measurements most people get wrong
Mistake #1: measuring at the wrong spot
Pools aren't perfectly rectangular. The dimensions printed on the original pool plans are nominal — the actual pool's widest point may be slightly wider, especially if the pool has rounded corners, a tanning ledge, or a curved Roman end.
Walk around the pool with a tape measure. Find the widest point of the pool. Then find the widest point that the cover would actually span. For a rectangular pool with a tanning ledge at the shallow end, the ledge width usually matters more than the deep end's width. The cover has to stretch across the wider one.
Mistake #2: measuring at water line, not deck level
The water line is below the coping. The coping juts out a few inches over the water. So the actual width at the level the cover sits on is wider than the water-line measurement by 4–8 inches total. Always measure at the coping edge, not the water line.
This single error is why a lot of "exactly the right size" covers end up an inch too narrow on each side and never quite seat properly. Add this 6 inches on top of your water-line measurement before sizing.
The sizing chart
Pool widths and matching reel tube lengths. Pool width is at coping (deck-level), so add 6 inches if you measured at the water line.
| Pool width (at coping) | Cover width | Minimum reel tube length | Recommended tube length |
|---|---|---|---|
| 10 ft | 12 ft | 13 ft | 14 ft |
| 12 ft | 14 ft | 15 ft | 16 ft |
| 14 ft | 16 ft | 17 ft | 18 ft |
| 16 ft | 18 ft | 19 ft | 20 ft |
| 18 ft | 20 ft | 21 ft | 22 ft |
| 20 ft | 22 ft | 23 ft | 24 ft |
| 22 ft | 24 ft | 25 ft | 26 ft |
Always size up if you're between numbers. A reel that's slightly too long is a non-issue — the cover just doesn't reach the tube ends. A reel that's slightly too short is a problem — the cover overhangs and bunches against the end caps.
Length doesn't matter for the reel
Note that we've only sized the tube length, not the pool length. That's because the reel sits at one end of the pool and the cover unrolls in the long direction. The tube only needs to be wider than the pool's narrow dimension. The pool's long dimension determines the cover length, but the reel tube doesn't care about that.
(One exception: pools longer than 40 feet may need a tube with a thicker wall or a center support stand to handle the cover weight. That's a tube material/structure question, not a length question.)
Tube diameter (the spec people forget exists)
Tube diameter affects two things: how the cover wraps and how compatible your reel is with replacement tubes.
Standard pool reel tubes come in four common diameters: 3 inches, 4 inches, 5 inches, and 6 inches. The most common are 4 and 5 inches.
- 4-inch tubes: lighter, cheaper, fine for pools up to 28 feet long with covers up to 14 mil thickness.
- 5-inch tubes: stiffer, less sag, recommended for pools 28–40 feet long or thicker covers.
- 6-inch tubes: commercial use, heavy covers, pools 40+ feet.
The reason this matters: replacement parts. If your motor is built for a 5-inch tube and you eventually need to replace the tube, you'll want a 5-inch replacement, not a 4-inch. The motor adapter is sized to the diameter.
Most quality reels list the tube diameter on the spec sheet. If it's not listed, ask. The Lux Pool reels (Milan, Verona, Paris) all use 5-inch tubes for the standard sizes, with 6-inch on Budapest and bespoke tubes on Rome commissions.
Custom-shape pools
What about freeform pools, kidney shapes, lagoon designs? They're trickier but not impossible:
- Measure the widest point the cover will span. Use that as your sizing reference.
- Custom-shaped covers cost more (they're cut to template rather than off a roll) but they exist.
- The reel itself is straight and rectangular — for highly irregular pool shapes, the reel rolls a rectangular cover that drapes over the pool edges. Some surface area at the corners may not be covered. That's normal and acceptable; you're not trying to seal the pool air-tight, just cover the bulk of the surface.
For pools with extreme shapes (long, narrow lap pools that bend, infinity edges, integrated spas), commission a custom reel. It's the situation Rome is built for: a one-of-one design sculpted to the specific pool. Standard reels just won't fit.
One more thing: deck space for the reel
Beyond pool dimensions, check that you have at least 24 inches of clear deck behind the reel for it to sit, plus another 12 inches in front for cover-edge handling. So you need a clear space of about 3 feet deep, equal to the reel's width.
If your pool deck is narrow (a deck only 3 feet wide along the long edge, common in zero-lot-line backyards), a standard reel may not fit. Options:
- Single-post stand reels (like the Lux Pool Milan) take less depth than twin-post designs.
- Mount the reel on a slight overhang outside the deck if there's grass or dirt behind.
- Commission a custom design with a vertical (folding) stand that tucks in when not in use.
Quick checklist before ordering
Before you click buy
- Pool width measured at coping level (not water line)?
- Cover width = pool width + 24 inches?
- Reel tube length ≥ cover width + 6 inches?
- Tube diameter matches what your existing tube uses (if upgrading)?
- 3 feet of deck space available behind the reel position?
- For pools 28+ feet long: tube wall ≥1.5 mm, or center support stand planned?
If you can answer yes to all six, you have the right size. If you can't, an extra 10 minutes of measurement now saves the time and shipping cost of a return later.
Most reels (including the Lux Pool collection) come in two or three standard widths. If your pool is in between, size up. The cover is the consumable part — you replace it every 4–6 years anyway. The reel is the part you're keeping for fifteen-plus years. Size the reel for the bigger possibility.