Here's the honest answer up front. If you want the least upkeep, choose composite. If you want real wood at the friendliest cost, choose pressure-treated. If you want wood that looks good and you'll keep up with oiling or sealing, look at cedar or mahogany. Now the part most people skip: none of it matters if the frame underneath isn't built right.
Start underneath: the framing matters most.
The boards are what you see. The frame is what holds you up. On most decks, the posts, beams and joists are pressure-treated lumber no matter what the surface is made of, because it's built to sit outside and resist rot.
- Footings that go below the frost line, so freeze-thaw doesn't heave the deck.
- A ledger bolted to the house and flashed so water can't run behind it.
- Joists spaced for the decking you choose; composite often needs them closer than wood.
- Hangers, bolts and screws rated for treated lumber, or stainless near salt water.
- Permits and inspections, which vary by town.
If you're resurfacing an old deck, the frame has to pass the same test. Putting new boards on a tired frame is how decks fail early. Before footings get dug, someone needs to call Dig Safe (811). Permit rules differ from one town to the next; see our page on deck building and repair in Lynn for an example of what to check.
The four main board choices.
Pressure-treated pine.
The most common and least expensive choice. It starts out greenish or tan and weathers to gray if left alone. It's strong and easy to work with, but it can check, split and twist as it dries, and it needs regular staining or sealing to look its best. Good choice for a practical deck, or if you like to paint or stain a solid color.
Cedar.
Lighter, softer and naturally resistant to rot and bugs. It has a warm color and a pleasant smell when it's new, and it fades to a silvery gray unless you seal it. Because it's soft, it dents more easily under furniture and pets' claws. A nice look for people willing to give it a little care.
Mahogany and other tropical hardwoods.
Dense, hard and very handsome, with a deep reddish color. It resists rot and wear better than softwoods, and it feels solid underfoot. It's harder to cut and fasten, so labor runs higher, and it also grays without oil. For many people, it's the best-looking wood deck you can build.
Composite and PVC.
Made from plastic, or a blend of plastic and wood fiber. No staining, no splinters, and cleaning is mostly soap and water. The tradeoffs: a higher price than most wood, it can get hot underfoot in full sun, and scratches can't be sanded out. Some people love that it looks the same year after year. Others miss the feel of real wood.
How New England weather treats each one.
- Summer sun fades wood and dries it out, which leads to cracks and raised grain. Composite fades a bit too, and gets hot.
- Snow and ice sit on a deck for long stretches. Shovel with a plastic shovel, push with the boards, not across them, and check with the board maker before using ice melt on composite.
- Freeze-thaw works water into every crack, which is why sealed wood and sound footings matter.
- Salt air near the coast is hard on fasteners and finishes. Stainless hardware and more frequent cleaning pay off.
- Shade on the north side of a house keeps boards damp, which invites moss and mildew on any material.
Railings and stairs.
Railings change the look of a deck more than the boards do. Wood railings can be painted, like the white posts and balusters above. Composite and metal systems need less care. Cable or glass keeps the view open. Railing height and the gap between balusters are set by the building code, so ask your building department what they need to see.
Stairs deserve the same attention. Every step should be the same height, because an odd one trips people. Add a handrail you can actually grip, and put a light at the top and bottom if you use the deck after dark.
Staining and sealing: what to expect.
Wood decks need a finish to keep water out and slow the graying. Fresh pressure-treated lumber is often too wet to take stain right away. Sprinkle some water on it: if it beads up, wait; if it soaks in, it's ready.
- Water soaks in instead of beading on the boards.
- The color has faded or gone gray in the sunniest spots.
- The finish is worn through on stairs and in front of doors.
- Boards feel rough or show raised grain.
The deck floor wears faster than the railings because it takes the sun, snow and foot traffic. Many homeowners recoat the floor more often and the rails less. A spring check is a good habit: wash it, look for loose boards and popped screws, and test whether water still beads. Composite skips the staining, but it still needs a good wash.
If water is getting into the room under your deck, start with our guide on a deck leaking into the room below. For building, repair, railings, stairs and staining, see our decks page.
Common questions
Composite and PVC. They don't need staining or sealing, just regular washing, though they cost more up front than most wood.
Only if the frame is sound and the joists are spaced closely enough for the boards you pick. Composite usually needs tighter spacing than wood, so the frame gets checked first.
Cedar looks nicer and resists rot naturally but is softer and costs more. Pressure-treated is tougher and cheaper, but it moves more as it dries and needs regular stain to look good.
