What it costs to build a deck in Portland

A new deck around Portland usually lands between $10,000 and $30,000, materials included. The typical figure is close to $16,000 for something near 300 square feet, which works out to roughly $37-$74 per square foot (Portland-area market data, November 2026) . The price moves with height above the ground, the board you pick, stairs and railing, tearing out an old deck, and a permit once the deck tops 30 inches.

If you already know you want one built, our deck building page shows what's included. This guide is about the money.

How much does it cost to build a deck in Portland?

Here are the Portland-area figures I work from. All of them are market data from November 2026, and every one includes materials.

If you've seen lower numbers online, that's usually because national cost pages blend in cheaper markets than ours. Read the table as what the local market charges; it is not our bid.

A lot of yards on the west side already have a deck on them, often one built with the house 25 or 30 years ago, which is common around Bethany. So the first money question on those jobs is whether the old frame can stay. The budget section below covers that.

What does a deck cost per square foot?

The market band for our area is $37-$74 a square foot with materials, based on decks close to 300 square feet. Multiply it out and you get the numbers below. This is per-foot arithmetic, not a quote, rounded to the nearest $100.

The catch is on the small end. A 12x12 deck still needs a set of stairs, a ledger board against the house, a railing if it's up off the ground, and the same day of layout and digging as a bigger one. None of that gets smaller when the deck does. That's why the market range starts at $10,000 and not at $5,300: small decks cost more per foot than simple multiplication says.

People also ask for labour per square foot. I don't split it that way here, because a per-foot labour number hides where the hours actually go. The next section breaks that down.

Where does the money go on a new deck?

In the market data we use, materials are about 45 % of a new deck and labour is the rest. Build time depends on the yard.

What surprises people is how much of that labour goes into parts you'll never look at again:

• footings and posts, dug and set to hold the whole thing up;
• the beams and joists, which are treated lumber whatever decking you choose;
• the ledger board fastened to the house rim, with flashing above it;
• stairs and the railing.

On a low deck, framing and footings eat up much of the labour even though they disappear under the boards.

The ledger joint matters more here than in a dry climate. Our rain runs down the siding and into any gap between the deck and the wall, and a ledger that wasn't flashed is where rot starts on an attached deck. Ask any bidder how they handle it.

If you want to see how we price other jobs, every job we price, with its range, is on one page.

How much do height and a sloped yard add?

Height is the cost driver most price pages skip. A deck that sits well off the ground needs taller posts, bigger footings and more bracing to keep it from swaying. It also needs a guard rail, and past a certain point, a permit.

That point is 30 inches. Oregon's 2026 residential code exempts a deck from a building permit when the surface you walk on is no higher than 30 inches over grade, measured at any spot up to 3 feet horizontally from where you'd step off. Go over that and the paperwork becomes part of the budget.

How much that costs you turns on the jurisdiction:

• City of Portland: above 30 inches you'll pay for a permit and for drawings (site plan, elevation, structural plans), and someone from the city signs off at a final inspection.
• Unincorporated Washington County: decks at ground level skip the building permit, though setbacks from property lines still count.
• City of Beaverton: check with Beaverton's building division and put their answer in the budget.

I can't give you a permit fee, because they vary. Ask each bidder to list permit fees and drawings as their own line so you can compare them.

Hillside lots run into this quickly. On West Slope, plenty of back doors sit at floor level while the yard drops away behind the house. Keep the deck level with the door and the low side can end up well past 30 inches, even when the high side is a step down.

Does the decking board change the price much?

It does, though less than people expect, because the frame underneath is pressure-treated wood either way. What the board changes is the cost of the boards themselves, the fasteners, and a railing to match.

Roughly, pressure-treated boards cost the least, cedar sits above them, and composite costs more up front.

The other half of the board decision is upkeep. Wood wants a wash, fresh stain and a sealer coat from time to time. The going rate for that is $550-$1,250 per deck, materials in, with $850 typical (Portland-area market data, November 2026). We do deck staining too.

Shade changes the math. Plenty of Cedar Mill homes went up in the 1960s or '70s beneath tall Douglas firs. Decks in that shade hold moisture longer and collect needles year round. Wood that dries slowly needs more attention than a board that doesn't soak up water.

What hidden costs show up on a deck job?

Most surprises on a deck job come from the old deck, not the new one.

Tearing out the old deck. Ask whether removal is in the quote and who disposes of the old lumber.

Rot behind the old ledger. Pull an old attached deck off and the rim joist, siding or trim it was hiding is often soft. Fixing that is its own line item. Local market figures for November 2026, materials in: rot repair costs $500-$4,000, usually about $1,500; replacing siding costs $900-$6,500, usually about $1,800. We handle that on the rot and siding repair side.

Older houses. If the house dates from before 1978, disturbing painted siding behind the deck brings up lead paint, which is work we stay out of. See what we don't do.

Digging footings. Oregon asks for a call to 811 at least two business days before any digging. The locate request is free, but it does push the start date.

Trees and planting. Removing a tree or planting around the finished deck is outside our work.

Can you build a deck for $5,000, or is repair cheaper?

At $5,000 you're near the bottom of what a new deck costs here. This ladder uses the same market rows (November 2026, with materials):

If you already have a deck and the joists and footings are sound, new boards cost a fraction of a rebuild. Before you price a new one, have the old frame looked at. Here's how deck repair works with us.

Is a deck or a patio cheaper?

A paver patio and walkway runs $2,154-$5,754 with materials, typically $3,947 (market data, November 2026). That row has no size attached, so don't read it against the deck numbers as a like-for-like comparison.

A patio skips the frame, the footings and the guard. A deck pays off where the yard slopes or the back door sits high.

How should you compare deck quotes in Oregon?

Two quotes only compare if they describe the same deck. Check that both list:

• the size;
• the height at the low side;
• the board and railing type;
• how many stairs;
• whether it's attached with a ledger or freestanding.

Then ask each bidder to price these as separate lines:

• the footing type;
• ledger flashing;
• the permit and drawings, where needed;
• tear-out, and who disposes of the old deck;
• rot repair, priced per unit or held as an allowance;
• the finish coat on a wood deck.

Get it in writing. In Oregon, any construction agreement above $2,000 has to be on paper, and no new deck in the ranges here comes in under that. The contract requirements guide spells out the required parts.