Herriman and the south Salt Lake Valley
Composite Deck Installation in Herriman, Utah
Capped composite and PVC decking, built on a frame spaced and gapped for the product rather than for wood. Most composite failures we get called out to are framing and gapping mistakes, not bad boards.
What is different
Composite changes the frame, not just the surface
Composite is sold as the low-maintenance option, and it is. What gets left out of the sales conversation is that it behaves nothing like wood, and the frame underneath has to account for that.
It is less stiff, so joists usually need to be closer together — commonly 16 inches on centre for a perpendicular layout and 12 for a diagonal one, though every manufacturer publishes its own figure and the warranty depends on following it. It also moves noticeably with temperature, and Herriman swings from the mid-90s in July to hard freezes by November. End gaps and side gaps have to be set for the temperature on the day of installation, using the manufacturer’s table.
Get those two things wrong and you get buckled boards, popped fasteners and gaps that open up in January. None of that is the board’s fault.
- Joist spacing set from the manufacturer’s span table for your board and layout, not from whatever the old frame happened to be
- End and side gaps set from the installation-day temperature, which matters more here than in a mild climate
- Hidden fasteners or colour-matched screws, using the clip system the board was designed around
- Airflow kept under the deck, because trapped heat and damp both shorten the frame’s life
What it covers
What a composite installation includes
Whether it is going on a new frame or an existing one, the frame gets measured against the board’s requirements before anything is ordered.
A frame built or adapted for the board
New frames get spaced correctly from the start. Existing frames get measured, and if joists need adding to reach the right spacing that is in the quote before you commit — not discovered halfway through.
Boards, fascia and trim
Deck boards, picture framing where the layout calls for it, stair treads and riser trim, and fascia to close the frame in. Composite looks unfinished without the trim, so it is quoted as part of the job.
Guards that match
Composite, aluminium or cable guards specified to work with the decking. Mixing a composite surface with an untreated wood guard is the fastest way to make a new deck look mismatched within two years.
Process
How a composite deck goes down
The order matters more than with wood, because boards have to acclimatise and the gaps are set against the temperature on the day.
Board selection
Colour, texture, capped composite versus PVC, and cost. Dark boards get hot in August sun — that is a real consideration on a south or west-facing deck and we will say so rather than let you find out.
Frame check or build
Span table checked against the chosen board and layout. On a re-deck we confirm the existing frame is both sound and correctly spaced before ordering anything.
Delivery and acclimatisation
Boards stacked flat on site so they reach ambient temperature. Installing straight off a cold truck first thing in the morning is how gaps end up wrong.
Layout and starter row
The first row sets everything after it. Squareness gets checked against the house and against the frame, because those two are not always the same thing.
Boards and fasteners
Hidden clips or screws per the system, with gaps set from the manufacturer’s temperature table rather than by eye.
Trim, guards and clean-up
Fascia, picture framing, stair treads and guards. Off-cuts removed — composite off-cuts are not firewood and should not be left behind.
Straight talk
What composite is good at, and what it is not
Good at: holding colour, resisting splinters and rot, and needing nothing but a wash. On a deck you want to walk on barefoot or put a young family on, that is worth a lot. It also removes the every-couple-of-years sealing job that Utah wood genuinely does need.
Not good at: being cheap, and being cool. Materials cost more than wood and the tighter framing adds to that. Dark boards in direct August sun get hot enough to be uncomfortable underfoot, and the darker and more textured the board, the more heat it holds.
Where we usually land: composite for surfaces people use constantly and do not want to maintain, wood where budget is the constraint or the deck is shaded most of the day. Neither answer is wrong.
- Choose a lighter board for a south or west-facing deck with no shade
- Budget for the frame, not just the boards — tighter spacing is a real line item
- Check the warranty terms, which usually require the published spacing and gapping to have been followed
- Plan on a wash once or twice a year. Composite is low maintenance, not no maintenance
Plan the cost
See the year composite overtakes wood
It prices the composite deck, prices the wood deck alongside it on the same footings and stairs, and works out the year the two have cost the same.
Thinking of re-decking an existing frame in composite?
Send a photo of the underside showing joist spacing. That one measurement decides most of the price difference between a straight re-deck and a partial reframe.
Questions
Composite questions
Can composite go over my existing wood frame?
Often, with two conditions. The frame has to probe sound, and it has to be spaced at whatever your chosen board requires. A lot of decks in this area were framed at 16 inches on centre, which suits many boards laid perpendicular but not a diagonal layout. Adding joists is straightforward — it just needs to be in the quote.
Does composite get too hot to walk on?
In direct summer sun, dark boards can. It is the same physics as a car dashboard: colour and surface texture drive it. A light board in partial shade is comfortable. A dark, deeply grained board on a west-facing deck with no shade will be hot from about two in the afternoon in July.
How long does composite last?
Manufacturers publish long warranties, typically measured in decades for capped products, and the surface generally outlives the frame beneath it. Which is exactly why frame quality matters as much on a composite deck as on a wood one — you do not want to be rebuilding a structure under boards that are still perfect.
Is PVC better than composite?
Different, not strictly better. PVC is lighter, holds colour well and does not absorb water at all. Capped wood-composite is usually less expensive, feels more solid underfoot and reads more like timber to most people. Both are sound choices; budget and appearance usually decide it.
Does it need sealing or staining?
No, and staining it would void most warranties. It needs washing — soap, water and a soft brush a couple of times a year, more often under trees. Avoid high-pressure washing, which can damage the cap and take the warranty with it.
Why do some composite decks buckle?
Almost always gapping. Boards installed tight, or installed cold and gapped as though it were warm, have nowhere to go when they expand. It is a preventable installation error, which is why the gap table is not optional.
Related work
Other things we do
Composite work usually sits alongside one of these, particularly when an older frame is involved.
Deck Installation
New decks laid out, footed and framed for your lot — from post holes to the last board.
See what’s involvedDeck Repair
Targeted work on rot, springy boards, failing ledgers and rails that move when you lean on them.
See what’s involvedDeck Replacement
Tear-out and rebuild when the frame is past saving, usually on the same footprint.
See what’s involvedGet a composite quote with the frame included
Send the form with your address and a photo of the existing deck if there is one. We will price the boards and whatever the frame actually needs.
Request a Quote
Tell us about your deck project below, including rough size, materials and photos if you have them, and we will follow up to set up a free estimate.