Patio cover cost

A patio cover costs $15 to $60 a square foot installed, typically around $30. A 300 square foot cover is therefore $4,500 to $18,000. An open pergola is at the bottom of that range; a solid insulated roof tied into the house is at the top.

The structural attachment to the house is what decides both the price and whether it leaks in ten years.

What it costs

Attached or freestanding

Attached to the house is the common choice: cheaper, because one side needs no posts, and it reads as part of the building.

The catch is the ledger, exactly as with a deck. A cover ledger bolted to the wall without proper flashing lets water in behind the siding and rots the rim joist. It is invisible for years and expensive when found.

It also has to tie into the roof or the wall in a way that sheds water, which usually means stepping the flashing under the siding. A cover attached with a bead of sealant along the top is the failure everyone eventually sees.

Freestanding adds two posts and 10 to 25% cost, avoids the ledger entirely, and can sit anywhere in the garden. On an older house with questionable wall construction, or where the roof line makes an attachment awkward, it is the better answer.

Open, louvred or solid

Open pergola gives dappled shade and no rain protection. It defines the space and it is what most people picture. Adding a retractable canopy between the rafters is $10 to $25 a square foot.

Louvred pergolas have rotating slats: open for sun, closed for rain, and motorised versions close on a rain sensor. They are genuinely the most useful of these and they cost two to three times an open pergola.

Solid roof gives full rain protection and makes the patio usable in weather. It also makes the room behind it darker, which is worth checking before committing, particularly on a north-facing wall or over a kitchen window.

Polycarbonate panels are the compromise: solid against rain, translucent for light. They are noisy in rain and they yellow over 10 to 20 years.

Snow, wind and the numbers that matter

A patio cover is a structure and it is subject to the same loads as a roof.

Snow load. In snow country a solid cover must be engineered for it, and a light aluminium cover sold for the south will fail. Ask what snow load the design carries and compare it to your local requirement.

Wind uplift. An open pergola is mostly transparent to wind; a solid roof is a sail. Post footings and the attachment have to resist uplift, not just carry weight.

The permit. Most jurisdictions require one for any permanent cover over about 100 to 200 square feet, and the inspection checks the footings and the attachment, which are the two things that matter.

Frequently asked questions

Will it make my house darker?

A solid cover over a south-facing patio reduces light into the rooms behind noticeably. Louvred or translucent covers keep most of it. Stand in the room on a bright day and imagine the roof before deciding.

Can I build a pergola myself?

Kits exist and are within reach for a competent DIYer, with two caveats: the footings must go below frost depth, and an attached ledger must be flashed properly. Freestanding kits avoid the second problem entirely.

Does it add value?

Covered outdoor living space is well regarded in listings, particularly in hot climates. It does not appraise like conditioned space, and a well-built cover reads as a feature while a sagging one reads as a repair.

Wood or aluminium?

Wood looks better on a traditional house and needs refinishing every three to five years. Aluminium needs nothing, spans further with fewer posts, and looks like aluminium. Powder-coated aluminium in a dark colour is the compromise most people are happy with.

What about just an awning?

A retractable awning is $15 to $45 a square foot, needs no footings and no permit in most places, and retracts in wind and snow. For rain and sun protection without a structure, it is the underrated option.