How to Pick the Right Carport Size

Most people pick a size by eye, order it, and find out at install that it's four feet too short. The building is already on the truck by then.

Sizing a metal carport comes down to three numbers, and they have to be decided in order, because each one limits the next: width, length, and leg height.

Width comes first

Width is the measurement across the front, from post to post. It's the number that decides whether the building works at all.

• 12 feet fits one vehicle with almost no room beside it. Fine for a compact car or a motorcycle and a mower. Tight for anything you need to walk around.
• 18 to 20 feet fits two small vehicles, or one vehicle with real working space beside it.
• 22 to 24 feet is where two full-size trucks stop being a squeeze. This is the most common width for a two-vehicle carport.
• 26 to 30 feet gives you two vehicles plus storage along one wall, or enough open floor to actually work in.

Available widths run 12 feet, then 18 through 30 in two-foot steps.

The mistake almost everyone makes is measuring the vehicle and stopping there. A truck is about 6.5 feet wide at the body and closer to 8 feet with the mirrors out. You also need room to open a door without hitting the post. Add at least three feet per vehicle on top of its width, more if someone in the household is not a patient parker.

Length is the easy one

Take your longest vehicle and add four to five feet. That covers the overhang at each end and leaves you somewhere to stand.

For reference: a midsize sedan is around 16 feet, a full-size crew cab truck around 20 to 21 feet, and a travel trailer anywhere from 20 to 40 feet before you count the tongue.

Lengths run from 20 to 60 feet in five-foot steps on a vertical roof. Regular and A-frame roofs stop at 35 feet.

If you're covering an RV, measure it yourself rather than trusting the brochure length. Manufacturers quote the box, not the bumper, and the difference is often two or three feet.

Leg height is measured at the eave, not the peak

This is the single most misunderstood number in the whole order. When a building is described as having 9-foot legs, that's the height of the side wall where the roof meets it. The peak in the middle is higher, but you can't park under the peak — you drive in under the eave.

• 6 to 7 feet clears any normal car.
• 8 to 9 feet covers a truck with a rack, a lifted truck, or a van.
• 12 to 14 feet is RV territory. Measure from the ground to the top of your air conditioner, then add a foot.

Legs are available from 6 to 16 feet.

Leg height also controls what doors you can fit. A roll-up door needs clearance above it for the header and the drum the door rolls onto, so a tall door needs taller walls than its own height. If you know you want a 10-foot door, you're looking at taller legs than you might expect.

Roof style changes more than looks

There are three, and the difference is real.

Regular roof has rounded corners and the panels run horizontally, front to back. It's the least expensive and it's fine for a simple open carport in a mild spot. It's only offered up to 35 feet long. Lean-tos require a vertical roof, so neither a regular nor an A-frame roof can take one.

A-frame gives you the familiar peaked shape with horizontal panels.

Vertical roof is peaked, but the panels run down the slope instead of across it. That's the important part: water, leaves and snow slide off instead of collecting in the seams. Anything with real length, and anything you plan to enclose, should be a vertical roof. It costs more and it's the one worth paying for.

Every building we install in North Carolina is certified for 150 mph wind and 35 psf snow load.

Size for the vehicle you'll have, not the one you have

Buildings last decades. Vehicles don't. It's easy to size a carport exactly around the car you drive today, then buy a truck, or a camper, or start keeping a mower and a four-wheeler under there too.

Going up one width step is a small part of the total cost. Replacing the building because you outgrew it is not.

A quick way to check yourself

Before you order, go stand where the building is going and mark the corners with stakes or spray paint. Park in it. Open the doors. Walk around. Ten minutes on the actual site tells you more than any amount of measuring on paper.

Once you have your three numbers, you can build the exact configuration on our estimator and see a price right away — including doors, windows, lean-tos and colors. No phone call required, and no obligation.