Propane Tank Cover Sizing Guide: 20lb, 30lb & Dual Setups

The right propane tank cover size comes down to three things: how many cylinders sit on your trailer tongue, whether they are 20 lb or 30 lb, and how much room you have around the regulator. Get the height wrong and the lid will not close. Get the width wrong and the cover rattles on the rack every time you hit a pothole. This guide covers standard tank dimensions, how covers are sized, and what to measure before you order.

Standard Propane Tank Sizes for Travel Trailers

Most bumper-pull travel trailers in Canada carry one or two portable steel cylinders on an A-frame rack. Two sizes cover almost every setup.

The diameter barely changes between the two. A 30 lb cylinder is essentially a taller 20 lb cylinder, which is why covers for both sizes share the same width and depth and only differ in height.

Dimensions vary slightly by manufacturer, so treat these numbers as a starting point and measure your own tanks. Aluminum and composite cylinders are shaped differently from steel and often will not fit a standard hard cover. Motorhomes and some larger fifth wheels use a permanently mounted tank built into the frame, which sits in its own compartment and does not take a tongue-mounted cover at all.

How to Tell What Size Your Tank Is

The fastest check is a tape measure. Measure from the base of the cylinder to the top of the valve collar. Under 19 inches, you have a 20 lb tank. Around 24 inches, you have a 30 lb.

You can also read the collar, the steel ring that protects the valve. Canadian cylinders are stamped with the tare (empty) weight, water capacity, and the month and year of manufacture. While you are there, check that date. According to the Canadian Propane Association, cylinders must be requalified or replaced ten years after manufacture, and an expired cylinder cannot legally be filled. There is no point sizing a cover around a tank the filling station will turn away in the spring.

Single vs Dual Propane Tank Covers

Single covers fit one 20 lb cylinder and open through a lid on top. They suit tent trailers, smaller campers, and owners who run a single tank.

Dual covers fit two cylinders side by side on the A-frame, the standard setup on most travel trailers. They are wide enough to enclose both tanks plus the changeover regulator between them, with a hinged access panel so you can open valves and switch tanks without pulling the whole cover off.

Here is how the Camco hard covers we carry compare:

Width and depth are identical on both dual covers. The only difference is about 5.75 inches of extra height on the 30 lb version, which matches the height difference between the tanks.

Mixed Setups: One 20 lb and One 30 lb Tank

Plenty of owners end up with one of each after a tank exchange. The rule is simple: buy the cover for the taller tank. A 30 lb dual cover fits over a 20 lb and a 30 lb side by side, with some headroom above the smaller one. A 20 lb cover will not close over a 30 lb tank.

The same logic applies if you plan to move up to 30 lb tanks later. Buying the 30 lb cover now saves you from buying twice.

What to Measure Before You Buy

1. Tank height, from the rack to the top of the valve collar.
2. Rack width across both tanks, including the regulator in the middle.
3. Depth clearance between the tanks and the front wall of the trailer. Dual covers need about 15.5 inches, plus a little room to lift the cover off.
4. Add-ons at the valve. A propane level gauge, like the Flame King glow-in-the-dark gas meter, sits between the valve and the pigtail hose and can add height. Check that the lid still closes with it installed.
5. Regulator access. The changeover lever should line up with the access panel so you can switch tanks without removing the cover.

Why a Cover Matters in Atlantic Canada

A tank cover protects more than the tank. Its real job is keeping sun, rain, road grit, and snow off the valves and the regulator. That regulator has a small vent that needs to stay clear. Road spray packing into it, or water freezing in it, can affect how gas gets delivered to your furnace and stove. Our guide to single-stage vs two-stage propane regulators explains why the vent should always face down and when a regulator is due for replacement.

Salt matters here too. Road salt through the spring and the salt air along the Northumberland Strait speed up corrosion on brass fittings and steel collars. In summer, UV fades paint and hardens plastic. A white cover reflects more heat than black, which some owners prefer for tanks that sit in full sun all season.

One thing a cover should never do is seal the tanks in. Propane is heavier than air, and covers are built with an open bottom so any gas from a leaking fitting can escape instead of pooling. Do not wrap tanks in a tarp or plastic bag as a substitute.

A cover also cannot warn you about a leak. If you smell rotten eggs near the tongue, close both tank valves and check your connections. Inside the trailer, your LP detector is the warning system that counts. Our comparison of RV propane detectors vs carbon monoxide detectors covers what each one detects and where to mount it.

Hard Cover or Soft Cover?

Hard polymer covers hold their shape, deflect stones kicked up from the tow vehicle, and have a hinged or removable lid for valve access. They last for years and are the style most travel trailer owners choose.

Soft vinyl covers slip over the tanks and cost less. They block sun and rain but offer little impact protection, and a loose soft cover can flap at highway speed. They work best on trailers that stay parked most of the season.

Repair Before You Replace

A cracked or lost lid does not mean buying a whole new cover. Camco sells replacement access doors for its single 20 lb cover and access door kits in black and Polar White for its dual covers, along with replacement thumbscrews and clips for the lid. If the shell is intact, swap the lid and keep going. For campground security, a Camco propane tank lock fits on the rack's threaded rod and locks both tanks in place.

Frequently Asked Questions

What are the dimensions of a 20 lb propane tank?

A standard 20 lb steel cylinder is roughly 12 to 12.5 inches in diameter and 17.5 to 18.5 inches tall. Exact measurements vary slightly by manufacturer.

Are all 20 lb propane tanks the same size?

Close, but not identical. Steel 20 lb cylinders from different makers can vary by half an inch or so. Aluminum and composite tanks differ more and may not fit a standard hard cover.

Will a 30 lb cover fit 20 lb tanks?

Yes. A 30 lb dual cover has the same width and depth as a 20 lb dual cover, just more height, so it fits over 20 lb tanks with extra headroom. A 20 lb cover will not fit over a 30 lb tank.

Is a 20 lb or 30 lb propane tank better for an RV?

A 30 lb tank holds about 50 percent more propane, which means fewer refills if you run the furnace on cool spring and fall nights. A 20 lb tank is lighter to lift and easier to swap at an exchange station. Many owners run two 30 lb tanks for extended trips and two 20 lb tanks for weekends.

How do I know what size my propane tank is?

Measure the height from base to valve collar. Under 19 inches is a 20 lb tank, around 24 inches is a 30 lb. The collar stamp also lists the tare weight and water capacity.

Browse our RV propane tank covers for Camco single and dual hard covers in black and Polar White, plus replacement lids and hardware. The rest of our L/P gas parts collection carries the hoses, fittings, detectors, and propane regulators that make up the rest of your setup. Not sure which cover fits your rack? Bring your trailer by 745 Route 133 in Boudreau-Ouest and we will check the fit with you before you buy.