Santa Monica · Deck Services
Deck Cleaning
Low-pressure washing and treatment that removes mildew, algae and salt film without damaging the boards.
Deck Cleaning · Santa Monica
Washing Without Wrecking The Boards
Deck power washing has a bad reputation because most of it is done wrong. A pressure washer at full tip on softwood does not clean the boards, it erodes the soft early wood between the grain lines and leaves a furred, striped surface that will drink water and grey twice as fast afterwards. The damage is permanent short of sanding the whole deck back. Done properly, the pressure is low, the tip is wide, the wand keeps moving, and the actual cleaning is done by a wood-safe chemical that lifts mildew, algae, salt film and general grime out of the grain while the water only rinses it away. That distinction is the entire job. On the Westside there is more to remove than most people realise. Marine air deposits a salt film that holds moisture against the boards long after the surface looks dry, shaded sections grow black mildew and green algae, and anything under a tree collects sap, pollen and tannin staining. All of that shortens the life of the finish underneath it and, on a pool surround or a stair tread, makes the surface genuinely slippery. We clean redwood, cedar, pressure treated, hardwood, composite and PVC decking across Santa Monica and the Westside, and where the finish underneath has gone we roll straight into Deck Staining rather than leaving bare wood exposed.
Why Have Us Wash It
Anyone can rent a pressure washer, and the results are all over the neighbourhood: striped boards, furred grain, wood fibres blasted out around every knot. We use low pressure and wide tips, we do the cleaning chemically rather than mechanically, and we neutralise afterwards so nothing is left in the wood to interfere with a future coat. We also look while we are down there. A wash is the best opportunity anybody gets to see the whole surface up close, so we check fasteners, probe anywhere that looks dark, and tell you what we found. Quite a few of our structural repairs start as a cleaning booking.
- Low pressure and wide tips, so the wood is cleaned rather than eroded.
- Wood-safe cleaners doing the work, with water only rinsing, and a neutralising rinse afterwards.
- Composite and PVC washed with the manufacturer-approved method that keeps the warranty intact.
- Boards, railings, stairs, fascia and skirt all included in the same visit.
- A condition report on fasteners, soft spots and anything structural we notice while we are on it.
- Sealing offered straight afterwards while the surface is clean and dry, which is the right moment for it.
Reasons To Clean A Deck
It is worth booking when any of these are true:
Black or green patches are spreading
Mildew and algae hold moisture against the boards continuously, which accelerates rot underneath and breaks down the finish above. They also make a surface slippery, which matters most on stairs and around a pool.
The deck is due for a re-coat
Every refinish starts with a clean. Applying stain over dirt, salt film or mildew is the most reliable way to make a good product fail within a year.
It is slippery underfoot
A slick surface when wet is almost always biological film rather than the material itself. Washing it off restores the grip the boards were supposed to have.
You live within a mile of the water
Salt film is invisible and it is constant in Venice, Marina del Rey and the beach side of Santa Monica. It holds moisture, corrodes fasteners and quietly shortens everything.
The composite looks dull or blotchy
Composite does not rot, but it collects the same grime and algae as anything else, and left alone it looks tired. Manufacturers specify how to clean it, and following that keeps the warranty valid.
You are about to list the house
A clean deck presents better than almost any other single item outdoors for the money, and it takes a day. Photographers notice, and so do buyers walking the yard.
Most decks are washed in a day, and it is the cheapest thing on this site that measurably extends the life of the structure. Call: (310) 564-8939
How A Wash Runs
A day on most decks, and the pressure gauge stays low throughout.
1. Assessment and protection
We look at the material, the finish and the condition, then cover planting, furniture and any adjacent surfaces. Composite gets the manufacturer method; wood gets the chemistry matched to what is growing on it.
2. Apply and dwell
A wood-safe cleaner goes on and is given time to work. This is the part that actually removes mildew, algae and grime, and skipping it is what pushes people into using damaging pressure instead.
3. Low-pressure rinse
Wide tip, low pressure, wand always moving, working with the grain. Railings, spindles, stairs, fascia and skirt all get the same treatment as the surface boards.
4. Neutralise, dry and report
A neutralising rinse where the cleaner needs it, then the deck dries. We tell you what we found on the way round, including anything soft, any popped fasteners and anything that needs attention before the next coat.
Materials, Growth And Timing
What changes between one deck and the next:
Softwood: redwood, cedar and pressure treated
These are the boards that pressure damages fastest, because the early wood between the grain lines is soft. Low pressure and chemistry are the only safe approach, and the tell-tale of a bad job is a striped, furry surface.
Hardwood: ipe and cumaru
Dense enough to take more pressure without eroding, but prone to raising a fine fuzz if overworked. Hardwood usually cleans up beautifully and is the material most improved by a wash followed by an oil.
Composite and PVC
Never rot, but do collect surface film. Every manufacturer publishes a cleaning method and a maximum pressure, and going outside it can void the warranty. We follow the specification for the brand on your deck.
Mildew and algae
Black spotting is mildew, green film is algae, and both live where moisture sits and sun does not reach. They come back faster in shaded, north-facing and tree-covered sections, which is where the interval should be shortest.
Salt film
Invisible, constant within a mile of the ocean, and the main reason beach-adjacent decks need washing more often than inland ones. It attracts and holds moisture and it accelerates corrosion at every fastener.
Tannin and rust staining
Dark streaks bleeding from knots and around fasteners are tannin reacting with metal or with moisture. There are specific treatments for it, and general cleaner will not touch it.
Washing before sealing
A wash is the first step of every refinish, and the surface has to dry to the right moisture content before any coating goes on. Booking the two together saves a mobilisation and gets the timing right.
Frequency
Once a year suits most Westside decks. Beach addresses, shaded gardens and anything under a heavy tree canopy are better on twice. Composite owners often leave it far longer than they should, because it does not look dirty until it suddenly does.
What Deck Cleaning Costs
Washing is priced by area and by how much is growing on the surface. The variables:
- Square footage, counting railings, spindles and stairs, which take longer per square foot than open decking.
- How much biological growth there is. Heavy mildew and algae need a longer dwell and sometimes a second application.
- Material. Composite follows a manufacturer method; hardwood and softwood each need different chemistry and technique.
- Whether stripping is needed. Removing a failed coating is a different job from cleaning, and it is priced as one.
- Access. Elevated decks, tight side yards and anything needing water carried a distance take longer.
- Whether sealing follows. Combining a wash and a re-coat in one visit is cheaper than booking them separately.
- Tannin and rust staining. Specific treatments cost more than a general clean and are quoted when we see them.
Cleaning is the least expensive item on this site and the one with the best return, because it is what makes the finish last and the finish is what makes the structure last. Booked together with Deck Staining it saves a visit. If the wash reveals soft framing, that becomes a Hillside Decks or rebuild conversation instead, and everything we do is listed under custom deck construction across the Westside.
Frequently Asked Questions
Will pressure washing damage my deck?
It can, and badly, if it is done at the pressure most people use. On redwood, cedar and pressure treated pine a narrow tip at high pressure erodes the soft wood between the grain lines and leaves a furred, striped surface that soaks up water afterwards. Once that has happened the only fix is sanding the whole deck. Done correctly the pressure stays low, the tip is wide, the wand keeps moving, and a wood-safe cleaner does the actual work.
How often should I clean my deck?
Once a year for most Westside decks. Twice a year if you are close to the water in Venice or Marina del Rey where salt film builds constantly, if the deck sits in shade, or if it is under a tree canopy dropping sap and pollen. Composite owners often leave it much longer because it does not look dirty, but the same film builds up and the same algae grows on it.
Can you clean a composite deck?
Yes, and it needs it. Composite and PVC do not rot, but grime, pollen and algae film accumulate on the surface exactly as they do on wood. Every manufacturer publishes an approved cleaning method and a maximum pressure, and exceeding it can void the warranty on the boards. We follow the specification for the brand you have.
Do I need to seal after cleaning?
On wood, if the existing finish has failed, yes. A clean deck with no seal is bare timber facing the sun, and it will start greying within weeks. The best moment to coat is right after a wash, once the boards have dried to the correct moisture content, which is why we usually book the two together. On composite and PVC nothing is applied afterwards.
Will cleaning remove the grey?
Partly. A good clean lifts the dirt, mildew and algae and brings back a lot of the colour, and on a mildly weathered deck that can be most of what you wanted. Deeper UV greying is damage to the wood fibres themselves and only sanding removes it. We will tell you which one you have once the surface is clean, rather than promising a result the wash cannot deliver.
How long does it take?
Most decks are done in a day, including the railings and stairs. The surface then needs to dry, typically 24 to 48 hours, before anything is applied or heavy furniture goes back. Very large or heavily soiled decks, or ones that need a second application on stubborn growth, can run into a second day.
Planning a deck in Santa Monica?
Tell us what you want to build and where it sits, and we will come out this week with a free estimate and a fixed price.
Or call us now: (310) 564-8939