If you’re searching “pvc deck boards,” there’s a good chance the product showing up in results isn’t actually the one you need. PVC deck boards and vinyl deck membrane are both made from the same base material, but they’re built as two different formats solving two different problems.
Search results and supplier listings both use “vinyl decking” as an umbrella term for either product. That’s where the confusion starts. A shopper comparing gapped, plank-style PVC boards against a fully adhered membrane system is really comparing a walking surface to a waterproofing system, even though every listing on the page calls itself “vinyl decking.”
Get that wrong before you call a contractor and the call gets wasted. Ask a board supplier to quote a second-storey deck sitting over a finished basement suite, or ask a membrane installer to quote a simple patio over open gravel, and neither one is set up to give you a straight answer. You’ll end up with a quote for the wrong job.
DeckRite manufactures the membrane half of this comparison: a fully adhered, heat-welded PVC sheet system. That’s worth knowing up front, since it shapes which side of this comparison we can speak to firsthand. This guide covers both formats fairly regardless, because picking the wrong one costs you more than picking the wrong colour.
PVC deck boards are individual capped or extruded plastic planks, installed over joists with gapped seams, the same way you’d install composite or pressure-treated wood decking. They’re made from cellular PVC, a foamed plastic with no organic wood content, which sets them apart from wood-plastic composite (WPC) boards that blend wood fibres with plastic polymers (Decks.com).
Each board spans a set joist spacing, and that span varies by profile and thickness, so check the manufacturer’s span table before you buy. Don’t assume your existing joist layout will work for a different board profile. Boards get fastened down with hidden clips or face screws, run in the same direction, and butted end to end with expansion gaps at the perimeter. The gaps between boards, typically a few millimetres, let rain and debris pass through to whatever’s below instead of pooling on the surface.
That gapped design is intentional. It’s how the format handles water in the first place.
PVC boards are a walking-surface product. Whatever sits underneath (open air, gravel, a crawl space) still needs to manage its own drainage independently.
That makes PVC boards a strong match for a ground-level deck over open ground, where letting water pass through to grade is exactly what you want. Day to day, the format behaves a lot like composite decking: low-maintenance, colourfast, resistant to rot, installed and replaced board by board.
If you’re actually weighing PVC against wood or composite as material families, rather than choosing between board and membrane formats, DeckRite’s decking material guide covers that comparison in full.
A vinyl deck membrane is a single, continuous sheet of PVC, heat-welded at every seam and fully adhered to a plywood substrate, so the walking surface and the waterproofing layer are the same piece of material.
There are no gaps for water to pass through, by design. Every seam is welded rather than overlapped, which turns the deck surface itself into the barrier protecting the framing, insulation, and living space underneath. Flashing at the perimeter, scuppers for drainage, and a slight built-in slope carry water off the deck instead of letting it find its way through one.
No board-based product performs that dual role of walking surface and waterproofing at once. Canada’s National Research Council evaluates PVC deck membrane products against the CAN/CGSB-37.54-95 standard, under a Type 4, Class B classification, as part of its Canadian Construction Materials Centre (CCMC) code-compliance evaluation process (National Research Council Canada). That evaluation is specific to membrane systems, which underscores how differently the two formats get treated once water management becomes a structural question rather than a surface one.
In our experience, that’s exactly why a contractor building a second-storey deck over a garage specifies a membrane system, and why board-and-gap decking would leave the space below exposed to whatever the weather sends down.
For the full technical breakdown of how a membrane system is built, seamed, and installed, see DeckRite’s guide to understanding vinyl deck membranes.
The core structural difference is water handling. Boards let water pass through gapped seams to whatever’s below. A membrane sheds all of it across a sloped, welded surface to a proper drainage system. That difference in job matters more than the price tag once you know which situation you’re actually building for.
| Factor | PVC deck boards | Vinyl deck membrane |
|---|---|---|
| Water handling | Passes through gapped seams to whatever’s below | Sheds all water via slope, flashing, and drainage |
| What’s required underneath | Open air, gravel, or ground that can manage its own drainage | A structural substrate, typically plywood, that needs to stay dry |
| Install method | Mechanically fastened planks with hidden clips or screws | Fully adhered, heat-welded sheet |
| Creates dry space beneath? | No | Yes, when detailed and installed correctly |
| Typical use case | Ground-level deck over open air or gravel | Second-storey deck or balcony over living space, a garage, or an enclosed area |
Not sure which column describes your deck? A quick conversation with a dealer clears that up fast, so you’re asking the right kind of contractor for the job you actually have. Speak with a decking dealer before you start collecting quotes.
That “what’s required underneath” row is where building codes get involved. In one British Columbia Building Code Appeal Board decision, the Board found that a deck, balcony, or exterior walkway that doesn’t permit free drainage of water through the surface has to be protected as a roof assembly under the Building Code, with the PVC membrane used for that protection required to conform to the CAN/CGSB-37.54-95 standard (Province of British Columbia, Building Code Appeal Board). Board-and-gap decking is built to let water pass straight through to grade, so it falls outside the trigger described in that decision.
Treat that BC decision as an illustration of the underlying logic rather than a ruling that applies automatically wherever you live. Code adoption and interpretation vary by province and by the building official reviewing your permit.
If your deck sits over living space, a garage, or anywhere water intrusion below is a real concern, the buildup that makes sense is a fully adhered membrane. If it’s a ground-level deck over open air or gravel, board-and-gap PVC decking is a legitimate, lower-cost option.
The deciding factor is structural. What happens to water once it hits the surface matters more than what the surface looks like, and that’s the same logic separating these two formats.
A few concrete scenarios make this easier. A rooftop deck over a suite, a balcony over a garage, a sundeck built above a walkout basement: all three have living space or vulnerable structure sitting directly below the surface, and a leak there causes real damage. That’s membrane territory, plainly.
A patio built at grade over gravel is a different situation entirely. Water reaching the ground below is the design working as intended there, so board-and-gap PVC decking can do the job well without the added cost of a fully sealed system.
That’s a structural decision. Once you know which side of it your deck falls on, the products and the questions to ask get a lot more specific.
Once you’ve concluded your deck needs a membrane, DeckRite’s product specifications page covers the installation details, and the supplier checklist is worth reading before you collect quotes from anyone.
The two formats get priced and maintained on different logic entirely, and that difference matters more than the sticker price on day one.
Boards get replaced or repaired plank by plank, the same way you’d service composite decking: pull the damaged one, swap it, move on. A membrane gets serviced and repaired as one continuous system instead, since a repair means patching or re-welding the sheet itself, and that kind of work usually calls for the original installer rather than a general handyman.
For DeckRite’s membrane specifically, real installed cost figures live in the vinyl decking cost per square foot breakdown rather than here, since project-to-project variation makes a single number in a comparison post more misleading than useful. Ongoing care is covered in DeckRite’s cleaning and maintenance guidance.
We don’t sell board-based decking, so we won’t hand you a number for it. What we’d suggest asking a board supplier instead: how individual boards are warrantied against fading and staining, what a typical board replacement costs against buying a full new deck, and how the fastening system holds up through freeze-thaw cycling in your region. Those questions tell you more than a sticker price ever will.
Both terms describe PVC-based products, but they’re not always describing the same format. “PVC decking” usually means gapped boards, while “vinyl decking” gets used loosely for both boards and membrane systems. Confirm the format before you assume which one a listing means.
No. A vinyl membrane is heat-welded directly over a plywood substrate. The membrane itself is the finished walking surface, with nothing else layered on top.
It depends on the deck’s location relative to living space. Second-storey sundecks and balconies over finished areas lean toward membrane systems because that’s where keeping water out matters most structurally, while ground-level patios see more board-based decking.
Sometimes, depending on the condition and structure of what’s already there. That’s a question for a contractor who can assess your specific deck in person.
If your research points toward a membrane system, the next step is getting a dealer’s eyes on your specific deck. Ask a dealer about your project and get connected with someone in your area who installs it.
