Composite and PVC
Composite decking in Amherst, NY
Composite ends the stain cycle, which is worth a lot in a climate with a short finishing window. It also moves with temperature, so it has to be installed to the board maker's numbers, not by eye.
Installation
Why do composite installs go wrong?
Composite is not wood and does not behave like it. Installed with wood assumptions it buckles, sags or voids its own warranty. The rules are all published by the manufacturer; the trick is actually following them.
- Gaps set to the board's spec
- Board surface temperature checked
- Joist spacing matched to the layout
- One hidden fastener system, not mixed
- Joist tape under every board
- Manufacturer instructions followed exactly
How to compare boards
How do you tell one composite board from another?
Composite and plastic deck boards get code recognition through a testing standard called ASTM D7032, and a board that passes can carry an evaluation report a building official will accept. It is a real, checkable quality signal, and it is not on any brochure.
- What gets testedBending strength, creep under sustained load, behaviour across temperature and moisture, ultraviolet exposure, freeze-thaw cycling, biological decay, how well the board holds a fastener, slip resistance and fire performance.
- Why freeze-thaw matters hereThat cycling test is not a formality in this market. It is the single condition a deck in Erie County is guaranteed to face, several dozen times a year.
- Capped versus uncappedCurrent composite wears a co-extruded polymer cap on its exposed faces for stain, scratch, fade and moisture resistance. First-generation uncapped board is a different and much weaker product wearing the same name.
- Cellular PVCNo wood fibre at all, so nothing in the board can absorb water or feed mould. It is the lightest and the most moisture-immune, and it usually costs the most.
- What to ask a contractorWhich product line, capped or not, and whether it carries an evaluation report. Three questions, and the answers separate a real spec from a colour choice.
Local fit
Why composite earns its keep in this climate
The argument for composite here is mostly about the calendar. A stain or sealer needs a dry substrate and moderate temperatures, and the Buffalo-area window for that is squeezed between spring rain and autumn cold. Miss it and the deck goes into winter unprotected. Composite and PVC take that job off the list permanently. The catch is movement: these boards expand and contract with temperature, so the gap between them is a specification rather than a preference, and installers check the surface temperature of the board itself rather than the forecast, because a dark board in the sun runs far hotter than the air around it.
No stain cycle, ever
Gaps set by specification
Board temperature checked
Warranty conditions respected
How it goes in
Frame first, because composite hides nothing
1
Choose
We go through capped composite against cellular PVC for your deck, the product lines, and what each one asks of the frame underneath it.
2
Frame
Joist spacing is set for the board and the layout, tape goes over every joist and beam, and the substructure gets squared before a board is cut.
3
Lay
Boards go down on one hidden fastener system with the specified side and end gaps, checked against the board's own surface temperature that day.
4
Finish
Picture-frame border, fascia, stair treads and the guard system, then the product paperwork handed over so your warranty is registrable.
Permit filedDrawings and survey go in to the Amherst Building Department
Footings verifiedDepth confirmed with the town, never guessed
Ledger bolted and flashedThrough-bolts and metal flashing, not nails
Debris hauledTo a facility permitted to take treated lumber
3-day cancellationYour right under New York home improvement law
More from us
The other things we do in Amherst
A composite surface is only as good as what it sits on, which is why most of our other work happens under the boards.
Deck Replacement
Old deck out, debris hauled to a permitted facility, new structure in its place.
Read more
Deck Repair
Heaved footings, soft joists, loose ledgers, and guards that move when you lean.
Read moreComposite Decking
Capped composite and cellular PVC, gapped the way the board maker specifies.
Read more
Covered Decks
Roofs, screens and three-season rooms, once the frame below is checked for the load.
Read more
Deck Staining
Cleaned, brightened and refinished when the moisture reading says it is ready.
Read moreService area
Decks across Amherst and Erie County
We install composite and PVC across Amherst and the towns around it, Williamsville and Snyder through Getzville, East Amherst and Swormville, and on into Clarence, Lancaster, Depew, Cheektowaga, Tonawanda and Kenmore.
Amherst
WilliamsvilleSnyderEggertsville
GetzvilleEast AmherstSwormville
ClarenceCheektowagaTonawanda
KenmoreLancasterDepew
Erie County
01
Cost and choice
Capped composite typically runs $40 to $70 per square foot installed around the Buffalo area, substructure included. Cellular PVC sits at the upper end of that or past it. Those are ranges from local market pricing, not a quote for your deck.
It depends how long you are staying. Pressure-treated is cheapest to install and the most expensive to keep looking presentable. Composite costs more up front and removes the stain cycle entirely. The crossover is a question of years in the house.
A cap is a co-extruded polymer skin on the exposed faces that resists staining, scratching, fading and moisture. Uncapped first-generation board has no skin and is a materially weaker product. Capped is the current standard and the one worth buying.
PVC has no wood fibre in it at all, so it cannot absorb water or feed mould, and it is the lighter board. That makes it the usual pick for shaded, damp and poolside decks. Composite gives a more convincing wood look for less.
Darker boards do, noticeably, the same as any dark surface in the sun. It is also the reason we read the board's own surface temperature when setting gaps, since a hot board is already near its maximum expansion.
02
Installation
Only after checking it. The frame has to be sound, square, and spaced for the board going on it. Some composite lines and any diagonal layout want joists closer together than a wood deck was framed for, and sag is not fixable afterwards.
Whatever the manufacturer specifies for that product, typically a small side-to-side gap and a slightly larger one where a board meets a post or a wall. Their instructions govern the warranty, so their numbers are the ones we use.
The boards have nowhere to go when they expand in the heat and they buckle. It is the single most common composite failure and it is entirely an installation fault, not a product one.
The clip system is matched to the grooved board, and mixing brands of clip, screw and board causes both spacing problems and warranty problems. We run one system through the whole deck.
Yes, and arguably more than wood does. The board on top will outlast the frame by years, so protecting the substructure is what stops you replacing an expensive surface because the cheap part under it rotted.