Composite vs. Pressure-Treated Decking for Florida's Coastal Climate

Neither material is the right answer for every Florida deck. Pressure-treated wood costs least upfront and is easy to repair, but it needs regular cleaning and sealing in Florida's sun and humidity. Capped composite costs about 1.6 to 1.7 times as much in our planning ranges and PVC about twice as much; both skip the sealing but get hot in full sun. On the coast, the bigger decision sits under the boards: nearly every deck has a pressure-treated wood frame, and its fasteners and connectors need to be hot-dip galvanized, stainless or another code-listed metal. Near salt water, the board and connector makers we checked call for stainless steel.

Composite vs. pressure-treated at a glance

What each option costs

Installed deck cost by decking material (per sq. ft. of deck; framing, footings and decking included, railings and stairs extra)

Item	Estimated range	What affects it
Pressure-treated wood	$25–$45per sq. ft.	Lowest upfront cost. Florida's sun, rain and termites make cleaning and sealing important.
Composite (capped)	$40–$75per sq. ft.	Wood-plastic boards over a pressure-treated frame. Lighter colors stay cooler in the sun.
PVC / premium cellular decking	$50–$90per sq. ft.	The least maintenance and the highest cost. Usually installed over a pressure-treated frame.

These ranges cover the deck surface, framing and footings. Railings and stairs are priced separately. The per-square-foot figure is the useful unit here, because the decking material is what changes between the three options.

Published Melbourne figures

One cost-guide publisher's Melbourne page, using December 2021 prices, put pressure-treated pine decks at $17–$20 per sq. ft. installed and composite at $32–$34. Those figures are nearly five years old and sit well below our 2026 planning ranges, so don't budget from them. They do show the same pattern: composite at roughly 1.7 to 1.9 times the price of pressure-treated. We didn't find reliable, dated deck pricing for Brevard County that is any newer. For local factors, see deck cost in Brevard County.

Same deck, three materials

This illustrative scenario uses only the planning ranges above. It isn't a quote.

Assumptions: a raised 12 × 18 ft deck (216 sq. ft.), between 30 in. and 6 ft off the ground, with framing, footings and decking. It leaves out railings, stairs, permit fees, drawings and removing an old deck.

Comparing the low ends and then the high ends, composite adds about $3,200–$6,500 over pressure-treated wood, and PVC about $5,400–$9,700.

A deck more than 30 in. off the ground generally needs a guard; confirm with your building department. Our ranges put a pressure-treated wood railing at $30–$70 per linear foot and an aluminum or composite railing system at $50–$120. Assuming 30 ft of railing, that adds about $900–$2,100 in wood (30 × $30–$70) or $1,500–$3,600 for a system (30 × $50–$120). Stairs and other extras are in the Florida deck cost guide, and you can run your own size in the deck cost calculator.

Upkeep costs over time

Wood's lower price comes with recurring work. One lead-generation cost page for Melbourne lists deck refinishing at about $3–$6 per sq. ft. It shows no date, and we couldn't check how it was put together. At that rate, each professional refinishing of the 216 sq. ft. example (216 × $3–$6) would cost roughly $650–$1,300. How often you'd need it depends on sun, shade and the product. We haven't found reliable Florida data to turn that into a lifetime cost, so weigh composite's premium against what you'd realistically spend on upkeep, in money or weekends.

Salt air: the hardware matters more than the boards

Why the frame and fasteners are the weak point

Traditional composite decking can't be used as a structural product, so the posts, beams and joists under it are wood, usually pressure-treated. The same goes for most PVC decks. Whatever boards you pick, the frame is held together with metal: joist hangers, post bases, hurricane ties, ledger bolts, screws and nails.

FEMA's coastal corrosion bulletin says metal corrodes dramatically faster in coastal environments, and that stainless steel and thick hot-dip galvanized connectors and fasteners (G185 or heavier) improve corrosion protection. It also notes that sheltered spots, such as under eaves and porches, miss the rinsing that rain provides, so they collect more salt and corrode faster. Much of a deck's hardware sits underneath, out of the rain. FEMA adds that owners may not realize connectors need maintenance, that some corrosion is hard to inspect, and that corroded hardware may need replacing to keep the structure sound.

What the code says about fasteners in treated wood

The 2018 International Residential Code, the national model code, requires fasteners in preservative-treated wood, including nuts and washers, to be hot-dipped galvanized steel, stainless steel, silicon bronze or copper. For connectors such as joist hangers, the connector maker's recommendations set the coating, with ASTM A653 G185 galvanizing as the minimum where the maker gives none. There are narrow exceptions, such as steel bolts 1/2 in. or larger, and staples in treated wood must be stainless.

Florida's residential code listed the same fastener materials for treated wood in its 2004 edition, according to a Florida Building Commission overview. We haven't confirmed the current Florida wording, so treat the model code as a baseline and ask your building department or builder what applies to your permit.

The 2026 Florida Building Code adds a new section (1711) with corrosion-resistance requirements for fasteners and metal connectors within 3,000 ft of a saltwater coastline. A table sets the required level by distance and exposure, and fasteners fully embedded in concrete or mortar are exempt, according to the Florida Building Commission's summary of changes. The commission's 2026 work plan and a Florida roofing trade association both put the new edition's effective date at December 31, 2026. We haven't read the full section or confirmed how it applies to residential deck framing or to repairs, so ask your building department which edition your permit falls under and what it requires at your address.

What manufacturers recommend near salt water

• Deck screws. One composite decking manufacturer's fastener guide tells installers to use its recommended stainless steel screws in any area near salt water. It says problems caused by non-recommended fasteners aren't covered by its limited warranty, and that screws should sit flush, not countersunk. Read your product's own guide before anyone buys fasteners.
• Connectors. A major structural connector maker names Type 316 stainless steel as its top recommendation for marine and seaside applications, because the molybdenum in 316 improves resistance to salt. FEMA's bulletin also says Type 316 resists corrosion better than Type 304.
• When in doubt, go stainless. The same connector maker recommends 300-series stainless steel when the wood treatment or the exposure is unclear.
• Store-bought galvanized may not be enough. FEMA's connector fact sheet warns that galvanizing on readily available hardware may not be adequate or meet local coastal codes, and that special-order hardware or stainless steel may be needed.
• The treatment chemical matters. An ICC evaluation report for connectors says to check with the lumber treater and the connector maker for the right coating for a given treated-lumber product. Ask your builder which preservative the framing lumber uses.

Metals that shouldn't touch

Trade press reports that lightly galvanized hardware and aluminum flashing often failed in contact with copper-based preservatives such as ACQ and copper azole. On a deck, that points to a few specific questions: what the ledger flashing is made of, how aluminum railing posts are separated from the treated framing, and whether every screw and connector is the same type of metal.

Barrier island, lagoon and mainland lots

• Barrier island. Melbourne Beach, Indialantic, Indian Harbour Beach and Satellite Beach sit between the Atlantic and the Indian River Lagoon. FEMA's older coastal materials fact sheet says metal corrosion is most pronounced within 3,000 ft of the ocean, and that's also the outer edge of the new Florida code section. Find out how far your deck will be from the ocean before you choose hardware.
• Oceanfront lots. Brevard's Coastal Construction Control Line runs along the county's Atlantic coast from Port Canaveral Inlet to Sebastian Inlet. With certain exceptions, construction seaward of the line needs Florida Department of Environmental Protection approval, on top of whatever local permit applies. Check your parcel on the state's map before you plan a beachfront deck; see the CCCL guide.
• Lagoon and riverfront lots. Homes on the Indian River Lagoon face brackish water, not surf. We haven't seen local building officials say whether the lagoon counts as a "saltwater coastline" under the 2026 code. Given the connector maker's advice for unclear exposure, stainless hardware is the cautious choice.
• Inland lots. Away from the water, the model code's list for treated wood (hot-dip galvanized, stainless, silicon bronze or copper fasteners) still applies, and so do the connector maker's instructions for your lumber's treatment.

Our guide to salt-air corrosion on the Space Coast covers railings, screen enclosures and the rest of the house.

Need a contractor for this project?Request a deck estimate

Heat and fading in the Florida sun

Consumer guides say composite absorbs and holds heat in direct sun, while wood generally stays cooler, and that lighter colors help with either. PVC boards can also get hot in full sun, especially in dark colors. We didn't find measured surface-temperature data comparing the three, so compare them yourself: set sample boards of the colors you like in full sun for an afternoon, then check how they feel.

If the deck gets full afternoon sun with no shade, plan on a lighter color, some shade or both. See pergola costs or screen enclosure costs if you want to cover part of the deck.

Fading works differently for each material:

• Pressure-treated wood needs regular sealing or staining in Florida's sun and humidity, every few years by one Florida source's estimate. The finish, not the board, is what you renew.
• Composite and PVC don't need sealing, but their color can change. Some capped composite lines carry 25-year residential fade and stain limited warranties. The warranties we read cover only color change beyond a measured threshold (5 Delta E units), and one describes its products as fade resistant but not fade proof. Before choosing a color, read the warranty for the exact product: what counts as fading, what's excluded and what the remedy is.

Mold, mildew and humidity

Florida's humidity, summer rain and shade all encourage growth on deck surfaces.

• Composite. Lumber-dealer and contractor blogs say composite still contains wood fiber and can mold in Florida's humidity and rain; one says it's more vulnerable than some wood decking. Others say newer capped products have improved. Weigh the source: one of the critics sells competing hardwood decking. Either way, shaded and poorly ventilated decks need washing more often.
• Pressure-treated wood is treated to resist rot, mold and pests, but in Florida's humidity it still needs regular upkeep. A Tampa cost guide says pressure-treated and cedar decks need regular sealing or painting to keep humidity out.
• PVC has no wood fiber, which removes the main reason given for mold on composite. Dirt in shady corners still needs washing off.

For any deck, airflow under low decks and a frame kept off the soil help everything dry out after rain. Follow the board maker's cleaning instructions, and read the stain terms of its warranty for any time limit on cleaning up spills.

Termites and rot

FEMA's coastal building materials fact sheet says moisture and termite decay are common throughout coastal areas. They matter for every deck, because the frame is wood.

• Pressure-treated lumber is treated to resist rot and pests. Ask which treatment rating the framing carries, above-ground or ground-contact, and where each is used, for example in posts and framing close to the soil.
• Composite boards. One manufacturer's code compliance report found its composite planks equivalent to preservative-treated or naturally durable wood for resistance to weathering, Formosan termites and fungal decay. That's a code-evaluation finding for one product line, not a Florida field study.
• PVC boards contain no wood.

Whatever the boards, keep soil, mulch and stored wood away from the frame, and check posts and the ledger for damage when you inspect the hardware.

Maintenance over the years

FEMA recommends inspecting connectors and fasteners regularly in coastal areas, because some corrosion is hard to see and replacement may be needed to keep the structure sound. Give the hardware under the deck, where rain never rinses off the salt, the closest look. If you're resurfacing an old deck with composite boards, have the frame and connectors inspected before new boards hide them again.

Which decking suits which homeowner

Pressure-treated wood tends to suit you if:

• upfront cost is the main concern
• you're happy to clean and seal the deck yourself every few years
• the deck is small, low or likely to be rebuilt in a few years
• you want the easiest, cheapest board repairs

Capped composite tends to suit you if:

• you plan to stay and want to skip sealing
• you're away for part of the year, or it's a rental, so nobody will be on hand to maintain wood
• the deck gets enough sun and airflow to dry out, or you'll wash shaded areas
• you choose a lighter color for a deck in full sun

PVC tends to suit you if:

• you want the least maintenance and can pay the highest price
• the deck sits in damp, humid conditions where you'd rather not have wood fiber in the boards

Consider a patio instead if the yard is flat and the door sits close to the ground. Compare a paver patio or read concrete vs. pavers.

Permits and HOA approval

Who issues a deck permit depends on where the home is. Brevard County Planning and Development permits work in unincorporated areas such as Viera, Suntree and Merritt Island, while cities such as Melbourne, Palm Bay, West Melbourne, Satellite Beach and Indian Harbour Beach handle their own permits. We didn't find a Brevard County page that addresses decks specifically, so ask your building department which permit applies, including whether replacing only the boards needs one. Our guide to deck, patio and pergola permits in Brevard County covers the local picture, and deck permits in Florida explains the general rules.

Florida's under-$7,500 permit exemption, available since July 1, 2026, doesn't cover structural work or work in a designated flood hazard area, and you have to request it in writing. A small wood deck can come in under $7,500, but building one usually involves structural framing, so don't count on the exemption without asking. See the $7,500 permit exemption.

If you have an HOA, check whether it limits deck materials or colors before you order boards. See HOA approval in Florida.

Common mistakes

• Using the wrong screws in treated lumber. Fasteners in treated wood need to be hot-dip galvanized, stainless or another listed material, and composite boards need the screws their maker specifies.
• Mixing metals. Lower-grade stainless fasteners in Type 316 connectors, or aluminum against copper-treated wood, invite corrosion.
• Buying off-the-shelf galvanized hardware for an oceanfront deck. FEMA warns that standard galvanizing may not be adequate on the coast.
• Putting new boards on a tired frame. Corroded hangers and soft joists hide under new decking. Inspect first.
• Ignoring the board maker's fastener rules. Problems caused by non-recommended fasteners may not be covered by the warranty.
• Choosing a dark color for a deck in full sun without testing samples.
• Reading "25-year fade warranty" as "won't change color." Check the threshold and the remedy.
• Comparing quotes with different hardware. One builder's price may include stainless connectors and another's plain galvanized. See why contractor quotes differ.

Next steps

1. Note how far the deck will be from the ocean or the lagoon, and how much sun and shade it gets.
2. Price your size with the deck cost calculator.
3. Find out who issues your permit, and get any HOA approval in writing.
4. Ask each builder for an itemized quote that names the board product, the framing lumber's treatment rating, the fastener and connector material and grade, the ledger flashing material and how the railing is attached.
5. Check the contractor's license and insurance with our contractor checklist.
6. Keep the product warranty and fastener guide with your house records, and inspect the hardware under the deck regularly.