A tent carries two waterproof ratings, and they are not the same number. MSR lists the Hubba Hubba LT 2 rainfly as solution-dyed 20-denier ripstop nylon with a 1200 mm polyether urethane coating and the floor as the same 20-denier nylon at 1800 mm, and on that page defines the unit plainly: a 1500 mm coating withstands a 1500 mm column of water for more than one minute before a drop appears. The floor gets the higher figure because a sleeping body presses water through a coating that rain never would. The condition that changes which number matters is the ground: on a dry pitch the fly rating governs, and on saturated ground the floor rating does.
The fly and the floor are rated separately
Coating ratings track fabric weight rather than quality. The Hubba Hubba LT 2 pairs a light 20-denier fly at 1200 mm with a 20-denier floor at 1800 mm, while MSR's Elixir 2 uses a 75-denier polyester fly at 1500 mm and a 75-denier polyester taffeta floor at 3000 mm. The heavier tent is more waterproof on paper and 2 lb 2 oz heavier in the pack, which is the whole trade in two figures.
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| Tent | Fly, as stated | Floor, as stated | Fly fabric | Minimum weight |
|---|---|---|---|---|
| MSR Hubba Hubba LT 2 | 1200 mm | 1800 mm | 20D ripstop nylon | 3 lb (1.36 kg) |
| MSR Elixir 2 | 1500 mm | 3000 mm | 75D ripstop polyester | 5 lb 2 oz (2.33 kg) |
| Big Agnes Tiger Wall UL2 | 1500 mm | 1500 mm | 15D ripstop nylon | not published on the page |
Big Agnes states one figure for both surfaces on the Tiger Wall UL2: recycled 15-denier nylon ripstop with a 1500 mm waterproof rating and no intentionally added PFAS, with solvent-free polyurethane taped seams. Equal ratings on a 15-denier fabric mean the floor is protected by a separately sold footprint rather than by its coating, which the same page recommends for exactly that reason.
A 15-denier floor is protected by a footprint, not by its rating
A coating rating says nothing about abrasion. Fifteen-denier nylon holding 1500 mm of water column has the same rating as a 75-denier polyester floor at 1500 mm and a fraction of its resistance to grit, roots and a dragged boot heel. MSR's guidance on its own tents is that a footprint cut to the model protects the floor from excessive abrasion and prolongs the life of the tent, and that some models pitch with the footprint, fly and poles alone. Big Agnes makes the same recommendation for the Tiger Wall UL2 and sells the footprint separately, which is a second purchase the tent's published weight and price both leave out.
Mildew is the other unpriced cost. MSR states that storing a wet tent for as little as 24 hours in warm weather is likely to start mildew forming, that mildew can permanently damage waterproof coatings by separating them from the fabric, and that mildew stains are not covered by warranty. That single sentence sets a maintenance rule no rating on the spec sheet implies.
Minimum weight and packaged weight are different numbers
MSR says it voluntarily follows ASTM International F 1934-98 on the two weights it publishes: packaged weight is the total weight of the contents off the shelf, and minimum weight is the tent body, rainfly and poles alone, without stakes, guy cords or stuff sack. On the Hubba Hubba LT 2 those are 3 lb 6 oz and 3 lb, so the parts left out of the smaller figure weigh 6 ounces. On the Elixir 2 they are 6 lb 3 oz and 5 lb 2 oz, a difference of 1 lb 1 oz.
A tunnel tent states the same two weights and leaves the coating out. Hilleberg gives the Anjan 2 a minimum weight of 3 lb 5 oz (1.5 kg) and a packed weight of 3 lb 15 oz (1.8 kg), with a Kerlon 1000 outer tent and two 9 mm poles, and publishes no millimeter rating at all. The 10-ounce gap there is the pegs and bags, on the same definition MSR names.
Floor area divides by the number on the label
Example, from the manufacturers' figures. The Hubba Hubba LT 2 has 32 sq ft (2.95 sq m) of floor and 16 sq ft of vestibule for two people, which is 16 sq ft each inside. The Elixir 2 has 30 sq ft of floor and 15 sq ft of vestibule, or 15 sq ft each. The Anjan 2 has 28.0 sq ft (2.6 sq m) of inner tent and 12.9 sq ft of vestibule, or 14 sq ft each. A 25-inch-wide, 72-inch-long sleeping pad covers 12.5 sq ft, so the label's occupancy number leaves between 1.5 and 3.5 sq ft per person for everything else, vestibule excluded.
Peak height sets the other dimension. The Hubba Hubba LT 2 is 40 in (102 cm) at its highest point and the Elixir 2 is 41 in, which is sitting height rather than kneeling height for most adults. Neither number describes usable width at the head end, where a tapered floor removes space a rectangular plan keeps. A headlamp on its lowest setting and a sleeping bag rated for the season both change how much of that volume gets used.
Before you buy a camping tent
- The fly and floor coating ratings as two separate millimeter figures.
- The fabric denier beside each rating, since 15D at 1500 mm and 75D at 1500 mm wear differently.
- Minimum weight and packaged weight, and what the packaged figure adds.
- Floor area in square feet divided by the occupancy on the label.
- Whether seams are taped from the factory and whether a footprint is sold separately.
- The pole specification and whether replacement poles and a repair splint are stocked.