12×20 gazebos

The metal hardtops cluster around $1,500 to $2,000, so choose on the roof and on what comes in the box: Domi and the Kingston both include curtains and netting. The cedar kits split in two. Sunjoy’s sit close to its metal ones, while Backyard Discovery and Yardistry cost more because the whole frame is cedar, and Backyard Discovery adds outlets and a 100 mph rating once anchored.

Costco sells a Yardistry 12×20 gazebo for $3,499.99 when we checked; on Yardistry’s own store the 12×20 Meridian is $4,199.99.

A 12×20 covers 240 square feet, about two and a half times a 10×10. That is room for a six-seat dining table at one end and a sofa with two chairs at the other, or a hot tub.

The roof size isn’t the room, though. The posts stand inside the roof line, so the clear space is closer to 18 by 10 feet, and the entry height under the beams is about six and a half feet.

Some can. Backyard Discovery sells its 20×12 Norwood and Barrington as gazebo-carports, with a solid cedar frame and a steel roof rated for heavy snow. It doesn’t publish the clearance under the beams, so measure your vehicle against the entry height in the manual before you order. For a single car on a narrower driveway, the same brand’s Stonebridge comes 20 feet long and 9.5 feet wide.

Aluminum needs only a hose to keep clean. Cedar looks warmer but needs restaining every year or two, and the all-cedar kits are much heavier to build. If you’re unsure, see metal gazebos and wood gazebos.

Start with something solid to bolt to. Backyard Discovery says its 100 mph rating only holds on concrete, and the anchors in its boxes are concrete anchors, so a deck or pavers need your own hardware. Its answer for a new base is a slab four to six inches thick, or concrete footers under each post.

Then plan the build. Owners of the Sunjoy Kingston report about two days for two people. The all-cedar kits take longer: many Norwood owners needed three or four people for the roof and spread the job over several weekends, and missing or damaged parts are the most common complaint.

The Kingston is rated for 50 mph winds and 3,700 pounds of snow across the roof, about 15 pounds per square foot. Domi rates its hardtop at the same 50 mph. Backyard Discovery claims 100 mph and over 12,000 pounds, but only once anchored as the manual describes. Owners of these kits describe storms passing without damage, and reports of a 12×20 hardtop failing in wind are hard to find.

Warranties are short on most of these kits. Sunjoy covers a year, Yardistry a year plus five on the lumber, Domi a year plus five on the hardtop structure, and Backyard Discovery five years, though its answers to buyers say storm damage isn’t covered.

The permit. At 240 square feet, a 12×20 is over the size many towns exempt, so ask your building department and your HOA first.

A base to bolt to. A concrete slab or footers for the cedar kits; the wind ratings don’t count on stakes.

Curtains and netting. Domi, the Kingston and the Cedar Dual-Track include them; check the listing for the others.

12×20 or 12×16. If you don’t need the full length, a 12×16 costs less and fits a smaller patio.