2×12 Pressure Treated Lumber Price by Length and Grade

A 2×12 is the most expensive common board on a deck framing list, and its price per foot climbs faster than its length. That surprises a lot of first-time builders. The 2×12 pressure treated lumber price at most US yards runs from roughly $20 to $35 for an 8 foot board up to $75 to $135 for a 20 footer, with ground contact treatment and premium grades adding 10% to 25% on top. Long, wide boards come from bigger, older trees, so they are scarcer and cost more per board foot.

Treat any 2×12 pressure treated lumber price you see online as a snapshot. Prices swing by region, season and the lumber market, so use these figures as planning ranges, not quotes. Call two or three local yards with your exact list before you budget. A 2x12x12 pressure treated board, one of the most common sizes for stair stringers and beams, usually falls between $30 and $60.

2×12 Pressure Treated Lumber Price by Length

General US retail ranges for southern yellow pine or similar softwood, No. 2 grade. Ground contact is the treatment level rated for posts, beams near grade and any wood in contact with soil.

Board feet use nominal size: a 2×12 is 2 board feet per linear foot. Dividing the price by board feet makes it easy to compare a 16 footer against two 8 footers, and you will often find the shorter boards cost less per board foot.

Actual Size of a 2×12

A pressure treated 2×12 is not 2 by 12 inches. Dressed (planed) lumber measures about 1.5 inches by 11.25 inches. Pressure treated boards often arrive wet from treatment and can be slightly fatter at first, then shrink a little as they dry. Lengths are usually cut a fraction over the nominal length, so a 12 foot board gives you a true 12 feet after squaring the ends.

• Nominal 2×12: actual about 1.5 x 11.25 in
• Weight: wet treated 2x12s are heavy; a 16 footer can take two people to carry comfortably
• Typical uses: deck joists on long spans, beams (doubled or tripled), stair stringers, rim joists, headers in outdoor structures

What Drives 2×12 Price Swings

Treatment level

Above ground lumber is treated for wood kept off the soil with good drainage and easy replacement. Ground contact lumber holds more preservative and is rated for wood in or near soil, hard-to-replace framing and areas that stay damp. Many builders now use ground contact for all deck framing because joists and beams are hard to replace. It usually costs a bit more per board.

Grade

No. 2 is the standard framing grade with some knots and wane. No. 1 and select grades have fewer defects and cost more. Construction lumber is often stamped “#2 & Btr” or similar. For stringers and visible beams, the straighter, clearer boards are worth the premium.

Length

Boards over 16 feet jump in price per board foot. Yards stock fewer of them and they often need special orders. If the design allows, splice beams over posts or add a beam so you can use 12 or 16 footers.

Species and region

Southern yellow pine dominates in the South and East and is strong for its size. Western yards often sell treated hem-fir or Douglas fir, which may be incised (small slits for preservative penetration). Shipping distance from mills adds to price in some regions.

Market timing

Lumber prices move with housing starts, mill output and tariffs. Spring and early summer demand can push prices up. Buying in late fall or winter, or locking in a quote for a whole deck package, can save money.

Where you buy

Big-box stores price individual boards competitively but may have picked-over stock. Local lumber yards often have better quality and will deliver a full package, sometimes with a contractor discount for large orders.

How to Estimate 2×12 Costs for a Project

1. Get the span right first. Use a span table for your species, grade, joist spacing and load to confirm 2x12s are needed. A 2×10 may do the job for shorter spans and save money.
2. Count joists. Divide the deck width in inches by joist spacing (often 16 inches on center), add one, then add rim joists and doubled joists at openings.
3. Add beams and stringers. Beams are often two or three 2x12s fastened together. Stair stringers are usually 2x12s cut on site, with three or more per stair.
4. Add 10% waste. Expect a few boards with crowns, splits or twist that you will not want in a critical spot.
5. Price by board foot. Compare lengths by price per board foot and choose the length that minimizes waste.

Example: a 12 x 16 foot deck framed with 2×12 joists at 16 inches on center needs about 13 joists at 12 feet plus two 16 foot rim joists. At mid-range prices that is roughly $500 to $900 in 2x12s before beams, posts, hardware and decking.

Framing hardware, posts, concrete and decking usually cost more than the 2x12s themselves, so the 2×12 pressure treated lumber price is only one line in the deck budget. Build in a cushion of 10% to 15% for price changes between quote and purchase, especially if you are buying in spring.

Tools and Materials to Plan For

• Circular saw with a sharp framing blade (a speed square helps for square crosscuts)
• End-cut preservative brush-on for cut ends of treated lumber
• Hot-dip galvanized or stainless fasteners and hangers rated for treated lumber
• Joist tape to shed water off the top of joists
• Gloves, safety glasses and a dust mask when cutting

Picking Good Boards at the Yard

• Sight down each board for crown, bow and twist. A slight crown is fine on joists if you install crown up.
• Avoid large loose knots near the edges, which weaken the board.
• Check the end tag for treatment level (above ground or ground contact) and intended use.
• Skip boards with deep splits at the ends; splits in long boards often grow as they dry.
• Stack and sticker wet boards flat in shade if you will not use them for a week or two, so they dry evenly.

Troubleshooting Common Problems

• Boards warped after delivery: Wet treated lumber twists as it dries in sun. Stack it flat with spacers and weight on top, and install soon.
• Fasteners corroding: Treated lumber corrodes plain steel. Use hardware rated for treated wood.
• Cut ends rotting: Treatment does not fully penetrate the core. Brush end-cut preservative on every cut.
• Price jumped since your quote: Quotes typically hold for a short window. Lock in large orders quickly.
• Long lengths out of stock: Redesign with an extra beam or splice over supports instead of waiting.

Handling Treated Lumber Safely

Wear gloves and a dust mask when cutting treated wood, cut outdoors, and wash your hands before eating. Never burn treated lumber scraps; dispose of them as your local waste rules require. Keep treated wood out of vegetable garden beds unless the label allows it.

When to Call a Pro

Bring in a licensed contractor or engineer for elevated decks, beams that carry long spans, hot tubs or heavy loads, and anything attached to the house. Deck framing usually needs a permit and inspection, and the inspector will check member sizes, spans and hardware. A pro can also produce an accurate lumber list so you buy the right lengths and do not overspend on 20 footers you do not need.