Skagit County Composite Decking Built for Burlington's Weather
Burlington sits close enough to the water and low enough in the Skagit Valley that decks here take a beating most inland homes never deal with. Salt-tinged air off the Sound and the delta, long stretches of driving rain from fall through spring, and a moss season that can run half the year all work against a deck that isn't built and finished correctly. Composite decking has become the go-to choice for a lot of Burlington homeowners for exactly this reason — it doesn't need refinishing, it resists the moisture cycling that splits and cups wood, and it holds up to the grime that salt air and shade leave behind. But composite is only as good as the substructure and installation underneath it, and that's where a lot of decks in this region go wrong.
What Skagit County Weather Actually Does to a Deck
It helps to understand the specific stresses at play here, because they shape almost every decision in a proper installation.
Salt Air and Corrosion
Burlington isn't right on the coast, but proximity to Puget Sound and the Skagit Bay tideflats means airborne salt reaches further inland than most homeowners expect. Over years, that salt accelerates corrosion on fasteners, brackets, and any exposed hardware. Standard zinc-coated screws and joist hangers can start rusting and staining a deck's surface well before the structure itself is due for attention.
Driving Rain and Moisture Cycling
Skagit County gets rain that comes in sideways as often as it comes straight down, which means water finds its way under rail posts, into end-grain cuts, and behind ledger boards if those areas aren't properly flashed and sealed. Wood decking swells and shrinks with every wet-dry cycle; even quality lumber will eventually cup, crack, or loosen fasteners under that kind of repeated moisture load.
Moss, Algae, and Shade
Between the rain and the tree cover common in this part of the valley, moss and algae growth is a near-constant issue on north-facing or shaded decks. Moss holds moisture against the deck surface, which is bad news for wood and can make older or lower-grade composite boards look tired fast. It's also a slip hazard on stairs and low-traffic areas that don't get enough sun or foot traffic to stay dry.
Why Composite Holds Up Better Here
Composite decking is made from a blend of wood fiber and recycled plastic, capped in most modern boards with a protective polymer shell. That cap layer is the real advantage in a climate like ours — it resists moisture absorption, doesn't require staining or sealing, and won't splinter or rot the way untreated or even pressure-treated wood eventually will. It's not maintenance-free in the sense of "never touch it," but it removes the sanding, staining, and re-sealing cycle that wood decks in this climate demand every couple of years.
| Factor | Composite Decking | Pressure-Treated Wood | Cedar |
|---|---|---|---|
| Refinishing needed | None — occasional cleaning only | Every 1-2 years | Every 2-3 years |
| Moisture resistance | High (capped boards) | Moderate, degrades over time | Moderate |
| Moss/algae resistance | Better on quality capped boards | Poor without regular treatment | Poor without regular treatment |
| Upfront material cost | Higher | Lowest | Mid-range |
| Typical lifespan (installed correctly) | 25-30+ years | 10-15 years | 15-20 years |
| Fastener/hardware exposure risk | Lower with hidden-fastener systems | Higher, visible fasteners common | Higher, visible fasteners common |
None of this means wood is a bad choice for every homeowner — cost and aesthetic preference are legitimate reasons to go that direction. But for Burlington's climate specifically, composite's resistance to moisture cycling and its low upkeep are why we recommend it as the default for most deck rebuilds and new builds we do in this area.
What a Correct Composite Deck Installation Actually Involves
The boards themselves get most of the attention, but the substructure and details underneath are what determine whether a deck lasts 10 years or 30 in this climate.
Substructure and Framing
Joists and beams need to be sized correctly for the span and load, and in our climate we favor treated framing lumber with corrosion-resistant fasteners rated for coastal or high-moisture exposure — standard hardware isn't sufficient given the salt air issue described above. Joist spacing also matters more with composite than with wood; most composite manufacturers specify tighter joist spacing than traditional lumber decking to prevent long-term sagging or board deflection.
Ledger Attachment and Flashing
Where a deck attaches to the house is the single most common source of hidden water damage. Proper flashing at the ledger board — installed so water sheds away from the house rather than behind the siding — is non-negotiable, especially with the rainfall patterns typical here. This is also one of the areas most likely to be shortcut on a low-bid job, since it's invisible once the deck is finished.
Drainage and Airflow Underneath
A deck built tight to the ground or without adequate airflow underneath traps moisture, which speeds up moss growth on the underside of boards and can accelerate framing decay even with treated lumber. We grade and gap for drainage and, where the site allows, leave enough clearance for air to move under the structure.
Fastening Systems
Hidden fastener systems (clips that secure boards from the side rather than screws driven through the face) are worth the extra labor cost in most cases. They keep water from pooling in screw heads, give a cleaner finished look, and reduce the corrosion staining that face-fastened hardware can develop over time in salt air.
Our Installation Process
1. On-Site Assessment
We look at sun exposure, drainage slope, proximity to trees or shade, and the condition of any existing structure. This tells us how much moss and moisture exposure the new deck will realistically face and shapes decisions on board color, ventilation, and railing materials.
2. Substructure Build or Repair
Framing, ledger flashing, footings, and joist layout are set to the load and span requirements for the composite product being installed — not just "what the old deck had."
3. Composite Decking Installation
Boards are installed with proper gapping for expansion and drainage, using hidden fastener systems where the product and budget allow, with attention to consistent seams and board direction.
4. Railings and Finish Details
Railing posts, fascia, and stair details are finished to match, with hardware selected for the same corrosion resistance as the rest of the build.
5. Final Walkthrough
We walk the finished deck with the homeowner, cover basic care, and point out anything worth watching — a shaded corner that may need extra cleaning attention, for example.
Living With Composite Decking in a Moss-Prone Climate
Composite decking is low-maintenance, not no-maintenance. In Burlington's climate, a periodic rinse or gentle scrub with a deck cleaner formulated for composite material keeps moss and algae from getting a foothold, especially on shaded sections. Pressure washing is generally discouraged unless done at low pressure with the right nozzle and distance, since aggressive pressure washing can damage the cap layer on some composite products over time. Keeping gutters clear and trimming back overhanging branches also goes a long way toward reducing the moisture and debris load that feeds moss growth.
Simple Seasonal Checklist
- Rinse or sweep debris off the deck surface regularly, especially in fall
- Clean shaded or north-facing areas more often than sun-exposed sections
- Check gutters and downspouts near the deck to keep water diverted away from the structure
- Inspect railing posts and stair connections annually for looseness
- Trim back vegetation that keeps sections of the deck shaded and damp
- Address any standing water or slow-draining spots before they become moss magnets
What Affects the Cost of a Composite Deck in This Area
| Cost Factor | Why It Matters |
|---|---|
| Deck size and shape | More linear footage, angles, and cuts increase labor and material waste |
| Composite board tier | Entry-level capped boards cost less than premium multi-tone or higher-density lines |
| Substructure condition | Rebuilding framing costs more than decking over sound existing structure |
| Fastening system | Hidden fastener systems add labor cost but improve appearance and longevity |
| Railing style and material | Composite or metal railing systems cost more than basic wood rail |
| Site access | Difficult grading, slope, or limited access adds labor time |
We won't quote a number without seeing the site, but these are the honest variables that move the price — anyone quoting a firm figure over the phone without visiting the property is skipping steps.
A Checklist for Hiring the Right Decking Contractor
- Ask specifically how they flash the ledger board and handle drainage underneath the deck
- Confirm they use corrosion-resistant hardware appropriate for coastal/salt-air exposure
- Ask which composite brands and product lines they regularly install and why
- Get a written scope that separates substructure work from decking installation
- Ask how they handle joist spacing for composite versus traditional wood decking
- Check that they carry proper licensing and insurance for exterior construction work
Why a Crew That Already Works Burlington Matters
A lot of the decisions above — joist spacing, flashing details, hardware grade, drainage — aren't things a homeowner can easily verify after the fact. They're buried under the decking. Working with a crew that already builds decks around Skagit County means those decisions are made based on what actually happens to structures in this climate over years, not a generic install process. We've seen how salt air, moss, and driving rain affect decks built without those details accounted for, and we build to avoid those problems from the start rather than fixing them later.
If you're planning a new composite deck or replacing an aging wood deck in Burlington, we're happy to walk the site, look at your sun and drainage situation, and put together a straightforward estimate — no pressure, no obligation. Use the form below to get started.