The right pressure for wood (it is lower than you think)
Wood is soft, and Florida weathering makes it softer. The grey layer on an untreated Jacksonville deck is UV-damaged lignin — the surface fibres have already broken down before you touch them.
So the technique is chemistry-led, exactly like house washing: apply a wood-safe cleaner, let it lift the grey and the mildew, then rinse at low pressure with a wide fan held well back.
| Material | Pressure | Nozzle | Notes |
|---|---|---|---|
| Softwood decking (pine, cedar) | 500 – 800 PSI | 40° | Most Jacksonville decks. Keep 12 in. back, move with the grain. |
| Pressure-treated pine fencing | 800 – 1,200 PSI | 25–40° | Harder than deck boards but still furs if you linger. |
| Hardwood (ipe, mahogany) | 800 – 1,200 PSI | 25° | Dense; tolerates more but shows wand marks readily. |
| Composite decking | 500 – 1,000 PSI | 40° | Clean cold; heat and harsh chemicals cause chalking. |
| Vinyl fencing | Under 1,000 PSI | 40° | Soft wash is usually enough; green film wipes off. |
| Aluminium / wrought iron | Under 1,200 PSI | 25–40° | Watch for loose paint and existing rust. |
Getting the grey out without wrecking the grain
Grey timber is not dirty, it is oxidised. Blasting it removes the grey by removing the wood, which is why a badly cleaned deck looks fuzzy and raised afterwards.
The correct sequence uses two products. A percarbonate or hypochlorite-based cleaner first, to lift mildew and break down the oxidised layer. Then an oxalic-acid wood brightener, which neutralises the cleaner and pulls the colour back toward the natural tone. The brightener is the step DIY jobs skip, and it is why professional results look even rather than patchy.
Deck and fence cleaning prices in Jacksonville
Fencing is priced by linear foot, decking by square foot. If we are cleaning both faces of a fence, the linear rate roughly doubles.
| Item | Rate | Typical job | Price |
|---|---|---|---|
| Timber deck | $0.25 – $0.40 / sq ft | 300 sq ft deck | $99 – $149 |
| Composite deck | $0.20 – $0.30 / sq ft | 300 sq ft deck | $79 – $119 |
| Fence, one face | $1.50 – $2.50 / linear ft | 100 linear ft | $150 – $250 |
| Fence, both faces | $2.75 – $4.50 / linear ft | 100 linear ft | $275 – $450 |
| Wood brightener | Included | — | $0 |
| Seal or stain after cleaning | $1.25 – $2.50 / sq ft | 300 sq ft deck | $375 – $750 |
If you are going to seal or stain afterwards
Wait. This is the single most common mistake we see on Jacksonville decks.
Freshly cleaned timber holds a lot of water, and Florida humidity means it releases that water slowly. Seal it too early and you trap moisture under the film — the coating peels within a season and you are back to bare wood, only now you have to strip the failed finish first.
Give it 48 to 72 hours of dry weather. If you want to be certain, sprinkle water on the boards: if it beads, the wood is still too wet to accept a finish; if it soaks straight in, you are ready.
What's included in every job
No line items appear on the invoice that weren't on the quote. Everything below is part of the price:
- Low-pressure wood-safe clean of decking, rails and steps
- Both faces of fencing cleaned where access allows
- Wood brightener applied to even out the colour
- Nail and screw heads checked; loose boards flagged
- Surrounding planting pre-wet and rinsed
Composite decking and vinyl fencing are cheaper than timber; both are cleaned cold. Read more in our Jacksonville pricing guide, or see what to ask before hiring anyone.
Expert tips from our crew
Things worth knowing whether or not you hire anyone. Several of these will save you money, and a couple of them will save you from a repair bill.
The water test tells you when to stain
Sprinkle water on the boards after cleaning. Beading means the timber is still saturated and a finish will peel within a season. Soaking straight in means you are ready — usually 48 to 72 hours.
Buy the brightener, it costs about $25
An oxalic-acid wood brightener neutralises the cleaner and pulls the colour back toward natural. Skipping it is the single most visible difference between a DIY deck and a professional one.
Work along the grain, never across it
Following each board end to end hides any variation in your passes. Working across the boards leaves stripes that show up the moment the timber dries.
Clean both faces of a fence, or accept faster regrowth
The shaded side is a reservoir of mildew that recolonises the side you look at. If the far side faces a neighbour's shed and the budget is tight, cleaning one face is a reasonable trade — just know why it greens up sooner.
