Composite and PVC decks
Skip the scraping and staining, and know what to ask before you choose a board.
Composite decking mixes wood fiber and plastic; PVC decking is plastic through and through. Neither rots the way wood does, and neither needs a coat of stain. In Duluth, where decks spend half the year under snow and spring brings weeks of meltwater and rain, that's why so many owners ask about them, especially for decks perched high on the back of a hillside house where staining means ladders and scaffolding.
What should you weigh?
- Up-front cost. Composite and PVC cost more than treated lumber. Most owners compare that against years of cleaning, sealing and swapping out split boards.
- Mildew and moss. Composite won't rot, but a shaded deck near the lake or under spruce and birch can still grow mildew on the surface. It cleans off, and some product lines resist it better than others.
- Movement with temperature. Boards expand and shrink. Gapping and fastening have to follow the maker's instructions for a climate that swings from well below zero to summer heat.
- Snow removal. Many manufacturers specify plastic shovels and approved ice melt. Ask what your board's warranty allows before the first storm.
- Heat and color. Dark boards get hot in full sun. On a south-facing deck, a lighter shade is more comfortable.
Can composite go on my existing frame?
Maybe. If the footings are deep enough, the ledger is bolted and flashed, and the joists are solid, a builder may re-deck over the old frame. Many composite boards, though, call for tighter joist spacing than older wood decks used, and the framing now has to keep pace with boards carrying long warranties. Expect the builder to probe joists, check the hangers and look for lateral load connections before agreeing to re-deck.
The frame still matters most
Composite boards sit on treated lumber, and the lumber is where these decks fail. Joist tape over the tops of joists and beams, flashing at the ledger, and fasteners rated for treated wood help the frame last as long as the boards. Duluth's deck packet lists the fastener types it accepts for treated lumber.
Matching guards
Most composite lines sell matching railings, and aluminum or cable guards keep a lake view open. Either way, the posts have to be anchored to the frame well enough to meet the guard rules on our stairs and railings page.
The builder prices the job after seeing the site, measuring, and going over materials and layout with you. We don't quote prices, and a number given over the phone before anyone has looked at the slope, the house wall and the footing locations is only a guess.
Where we connect you with help
Common questions
Is composite a good fit for Duluth?
For many owners, yes, because it avoids the cleaning and sealing that wood needs after long, wet winters. It costs more up front, so weigh it against how long you plan to stay.
Can I shovel a composite deck?
Usually, with a plastic shovel and an ice melt the manufacturer approves. Metal blades and some de-icers can scratch or stain boards, so check the care guide for your product.
Related services
More background: Duluth deck guide.
A deck that lurched after the thaw, or one you've been planning all winter?
Call the number above and we'll connect you with a deck builder who works on your side of the hill.