What Does a Custom Carport Cost in Snohomish & King County? (2026 Guide)

If you’re pricing out a carport for your Snohomish or King County property, the range you’ll see online is wide — and for good reason. A carport can be a simple freestanding metal frame or a fully custom, attached structure built to match your home. Here’s what actually drives the number, and how to get a figure you can plan around.

Metal Carport Pricing

Metal carports typically run $5 to $20 per square foot for materials, or roughly $15 to $30 per square foot installed. Custom metal builds with upgraded framing, enclosed sides, or higher wind and snow ratings can reach $40 per square foot. On a standard two-car footprint, that puts most metal carport projects somewhere between $2,000 and $12,000, with fully custom attached builds running $28,000 or more.

Wood Carport Pricing

Wood carports cost more to build — typically $15 to $30 per square foot installed, or $10 to $20 per square foot for materials alone. The labor is more specialized, since a wood frame is usually built to match the house rather than assembled from a kit. Overall, custom carport projects — wood or metal — land somewhere in the $3,000 to $18,000+ range depending on size, design, and materials.

These figures are general market data, not a quote from NW Structures — every lot and design is different. The only way to know what your project costs is a site-specific written estimate.

What Actually Drives the Cost

• Size. A single-car carport costs a fraction of a build sized for an RV or a boat.
• Attached vs. freestanding. Attaching a carport to your house or garage adds engineering and tie-in work that a standalone structure doesn’t need.
• Site prep. A sloped lot, existing concrete, or drainage work can add cost before the structure itself even starts.
• Snow and wind load. Western Washington’s building code accounts for our wet winters — a carport engineered for real snow load costs more than a bare-minimum kit, but it’s the difference between a structure that holds up and one that doesn’t.
• Permits. Requirements vary by jurisdiction — Snohomish County, King County, and individual cities each handle accessory structures a little differently. Your builder should pull the right permit for your specific address rather than assume one county’s rule applies everywhere.

Metal or Wood?

Metal is the faster, lower-cost option and holds up well with minimal maintenance. Wood costs more but blends into a property the way a kit-built metal carport usually can’t — it can be finished to match your siding, trim, and roofline. Neither is the “right” answer across the board; it depends on whether you want the carport to disappear into the house or simply do its job for the lowest cost.

This is the same reasoning that goes into any accessory structure on your property — it’s worth weighing against a fully enclosed garage if you want security and storage, not just covered parking. We build both, along with the custom carports and garages that make up a big part of our work across Snohomish and King County.

If you’re comparing builders, ask to see recent local work and get everything — site prep, permitting, and the structure itself — in one written number. That’s the only way to compare two quotes apples-to-apples. NW Structures is a family-owned shed, garage, and ADU builder based in Snohomish County, and we build carports on-site rather than dropping a prefab kit on your lot.

Common Questions We Hear

Do I need a permit for a carport? In most cases, yes — but the threshold and process depend on your jurisdiction and the structure’s size. Some smaller, fully open carports may fall under different rules than an enclosed or attached one. Don’t assume; check with your county or city before you build, or ask your builder to confirm before pricing the job.

Can I attach a carport to my existing garage? Usually, yes. Attaching to an existing structure can actually simplify the footing and roofline work compared to a freestanding build, though it does mean matching your existing roof pitch and siding if you want it to look built-in rather than bolted-on.

How long does a carport take to build? A straightforward metal or wood carport is typically a matter of days once permits are in hand and materials are on-site. Custom, attached builds with more site prep take longer — your builder should give you a realistic timeline as part of the estimate, not just the sticker price.

Will it hold up to our winters? That’s the real question, and it’s why we don’t recommend the cheapest big-box kit for anyone who wants the structure to last. Western Washington’s snow load and wind requirements exist because a carport that isn’t engineered for them can fail in a bad winter — ask any builder for their structure’s rated snow load before you sign anything.

Get a Real Number

Every lot is different, and the fastest way to know what your carport will actually cost is a site visit and a written estimate. Reach out to NW Structures and we’ll walk your property, talk through metal vs. wood, and give you a number you can plan around — not a range pulled from a national average.