How To Pressure Wash A Deck Before Staining [6 Steps To Get It Done]

By Power Tools

July 6, 2021

Cleaning the deck? Not so fun… Pressure washing the deck?  Oodles of fun:)

Pressure washing your deck before staining is a great way to prepare the wood for stain, in addition to the satisfying clean you get.

If you have a deck then, chances are you already know how hard it is to maintain, but it’s worth it.  I think we’ve all been on those ash grey decks that haven’t been taken care of.  

Some woods age better than others, but age takes it’s toll on all of us.  Just like a nice manicured lawn make our homes feel like home, a well maintained deck helps make our Sunday BBQ’s the best on the block!

Pressure washing deck
man cleaning deck with a pressure washer – high water power cleaner on wooden terrace surface

So here we go, how to pressure wash a deck before staining in 6 easy steps.

Pressure washers take the back breaking out the cleaning equation.  We love ’em.  And typically they do better work than a chemical based solution (better for mother nature too).  But if you fail to use your power washer properly then it just might damage your deck.

It has both the capacity to carve and to clean.  We want to leave the carving to those guys with the chain saws at the county fair. 

With high pressure and/or setting the nozzle too close to the wood, then it will etch the wood and do some permanent damage. Not structural, of course, but you’ll see it, and probably notice it every time you use your deck there after.

So use your pressure washer with care and don’t get in a hurry (the fan tip will probably be your safest choice).

It is not compulsory to pressure wash your deck before staining, but it will make for a better stain job in the long run.

What is Staining a Deck?

Stain is a coating that both protects the wood and brings out the woods dramatic natural colors and textures.

Your deck honestly faces a lot of stress, whether from the blazing sun to the beating rain to freezing drops in temperature.  Wood is beautiful, but only for as long as you take care of it and stain is a great way to do that.

Staining a deck will enhance the beauty of deck on your house and protect it from damage and thus extend the life of your deck.

Three primary ingredients: pigment, solvent, and binder are consisting of a commercial wood stain.

These components work for whether the stain is oil or water based, offer a variety of wood color, both darkening of wood and offering highlights of the grain and natural patterns.

Paint or stain is personal decision of course.  With paint your essentially hiding the wood (guess which my preference is;) and stain is more of compliment. 

While you can later paint over stain (but do your research first), you can’t stain over paint.  Not unless you trade in your pressure washer for a sandblaster and a lot elbow grease.

The Necessity of Cleaning Before Staining

It doesn’t matter whether your deck is brand-new or fully fresh or older and damaged, you really should clean your deck before staining on it.

Cleaning helps your stain to find a better finish and less stain encrusted crud you have to clean up later.  New or old, either way it’s best to clean your wood before staining.

Older decks, of course, should be cleaned even more thoroughly as they accumulate dirt and fungi and algae and dust and ect… If you use a finish before and the woods ready, you’re very likely to regret it later.

Advantages of Pressure Washers

  • It saves you valuable time. Manual washing and scrubbing is the pits.
  • Pressure washing improves curb appeal.
  • The operating procedure is easy and human-friendly.
  • Easily clean the tough grim, dirt, grease from any kinds of outwards or external appearance.
  • Requires less water and solvents than manual washing, so it is an environment-friendly process.
  • Takes very little space to store it after washing.
  • Protects your home from harmful fungi, algae, bacteria etc.

If your still in the market for Power Washer, check out: Great Pressure Washers To Own

how to winterize a pressure washer

The Cost to Pressure Wash Deck

Money.  We all need it.  We all want to spend it wisely..

Cost depends on its size, condition, type ect…  But on average, the cost to power wash your deck as estimated on each square feet varies from $0.25 – $0.45 USD. But cost depends on buying a pressure washer or hiring one temporarily on a daily or hourly basis.

You can clean a deck of about 500 sq.ft. with pressure washing, in about 1 to 1 1/2 hours. This will probably cost between $35 to $70 a day if you choose to rent a power washer

Required water for a regular pressure washer per minute will probably be less than 2 gallons a minute.  Less than a garden hose actually, check our our comparison here.

You may decide to use a sealant after removing any mold or mildew. This will cost about $17-$50 per 5 gallons for 300 sq.ft.

How to Pressure Wash a Deck Before Staining

So if you just buy a pressure washer and go to town cleaning with it, you might start to notice that your nice flat wooden board will turn into a shape that looks like a seashell.  This,unfortunately is a permanent condition.

A pressure washer is the source of a great deal of power.  That’s why we love ’em – right?  But it’s easy get injured or do damage if your not paying attention to what your doing or you get in a hurry. 

Taking your time could very well save you time in the long run, not to mention money, and health.

1. Safety Measures. The first step is always to avoid serious injuries. Wear a goggles or some form of eye protection. Closed-toe shoes for your piggies. Always keep all body parts out the direct spray. Do not point the nozzle at any person or pet.

Short pants, loose clothing, and jewelry should probably be avoided.

When using a gas power washer, don’t forget the engine gets hot after a time, so be careful when you move it.

2. The Site Should be Prepared, remove all loose debris that is adjacent to the deck. To prevent tripping and tangling hoses you have to remove all related obstacles.  Prepare your work area so you can focus on the cleaning job and not be distracted irritating obstacles that slow your work flow .  Wind is another distraction at times, so pay attention to the weather.

3. A Cleaner Has to be Applied Wisely. Firstly, follow the manufacturer’s instructions to set up. Check out the washer’s manual option to fix a proper spray pattern for your wooden deck. Now use low-pressure soap-dispensing nozzle and add the solution in the required manner. Then power up the machine and spray solution from top to bottom of the deck.

Read Also: Pressure washer detergent for cleaning deck

4. Use a Utility Brush and Rotating Scrub Brush, for typical places and tight corner, use a utility brush to bleach the solution. Utility brush should be synthetic in form and a long-handled. Long handle will help to reach all stubborn dirty place. And a rotating scrub brush is used to remove heavy spots and dirt.

5. Start Rinsing With the Conventional Widest Nozzle, move with the perfect angle with the trigger. A 40 degree to 60-degree tip size is the standard degree of angle from where the water emerges. You have to concern about the pressure you supplied. If you wash with high pressure it will etch the wood surface. The damage is permanent and you cannot overcome it. Use 500-600 psi(pounds per square inch) for softwood, and 1200 psi or less than that for harder wood.  Maintain the nozzle 6 feet away from the deck surface.

Read Also: The pressure washer nozzle mystery

6. After Successfully Cleaning the Deck power off the Machine and chose an appropriate and your desired wood stain for further beautify it.


Your deck is probably your favorite place to pass leisure time and to recreation purpose. It’s a neat and clean environment may refresh your mind. To maintain it, regular washing is necessary.

When you clean it and unconditionally you get injured, then it will useless. So be careful using the pressure washer.

  • After buying one read through the indicators supplied by the manufacturer because each machine is different.
  • Always wear safety goggles to protect your eyes from the chemical. Enclosed running shoes, musk, long pants have to wear for protection.
  • Don’t use a gas pressure washer in confined areas it has the possibility to take carbon monoxide by breath excreted from combustion engines.
  • Kids not allowed when cleaning operation is running.
  • If you want to hire a professional cleaner, make sure whether they are well trained or not.

What PSI do I need to wash my deck?

PSI stands for pressure per square inch and is essentially a measure of the strength of the water jets emitted by the pressure washer.

Different material types will be able to withstand varying pressures, so you should check with the manufacturer of your deck for their recommended PSI setting.

If you cannot find the manufacturer’s information, we recommend starting with a lower PSI setting and gradually increasing the pressure. 

Softer woods such as pine and cedar will need a lower pressure than harder ones. For soft woods, you are looking at an ideal PSI of about 500 to 600. If your deck is a harder wood such as oak, it can withstand up to about 1,200 PSI.

You should never exceed 1,500 PSI otherwise you can cause serious damage to the deck. This should easily and safely remove all embedded dirt and grime from your deck.

How do you properly power wash a deck?

If your deck is covered in a layer of grime, you can use a stiff-bristled brush and water or a mild detergent first. This will help to break up the layer a little, making pressure washing much easier. 

Once you have filled, activated, and tested your pressure washer you are ready to begin cleaning your deck. Hold the wand about 12 inches from the surface of the deck and squeeze the trigger.

Use a side to side sweeping motion to cover the deck and try to cover all areas evenly. 

You should move the water jets in line with the grain of the wood, parallel to the direction the boards are laid in. If your deck is particularly dirty, you can use a chemical cleaner containing sodium hydroxide to help make the task easier.

Make up a solution according to the manufacturer’s instructions and apply before rinsing off. 

Can you power wash a pressure-treated deck?

Many people choose to use pressure-treated wood for their deck as it is more resistant to insects and rotting. It is also more suitable for use in environments where it will be exposed to moisture. This is due to the inclusion of chemicals in the wood, which have the potential to seep out. 

This is a debated issue. Some people do not recommend using a power washer as it can cause damage to your deck and cause the harmful chemicals to seep out into your garden.

Other people advocate for the use of a pressure washer but simply recommend taking caution with the PSI and distance between the nozzle and your deck.

Again, if you are unsure we would recommend checking with the manufacturer for more detailed care instructions. In some cases, using a power washer on your deck can void the warranty, another important factor to check prior to using a power washer. 

Is it better to sand or pressure wash the deck?

Many people will recommend both sanding and washing your deck for the best quality clean. If you have a pressure-treated deck, you may wish to just sand it. This prevents escaped chemicals, such as arsenic, from splashing about your garden. 

The decision of whether to sand or power wash your deck really depends on your desired outcome. If you wish to re-stain the deck then you should do both processes ideally. You should wait for the wood to dry completely before attempting to sand it.

It is generally advised to perform cleaning of the deck with a pressure washer first. You can add some cleaning solution, stripper, or brightener to the water tank for some extra power.

Sanding can then be done afterward to remove any tough spots. Sanding takes much longer and it is rarely recommended that you sand the entire deck.

Do I need to sand my deck after pressure washing?

As mentioned above, yes you should generally sand your deck after you have pressure washed it. The water causes small splinters of wood fibers to stick up from the decking.

If these are left they could cause splinters and other injuries, or just ruin the aesthetics of your deck. If you are planning on painting or staining your deck, this will help the finish to apply more smoothly.

You should use sandpaper that has a grit of no more than 60 to 80. This is the optimal level of sanding for stain penetration. Higher grits will create a very smooth finish on the wood. While this may sound good, it will not allow the stain to penetrate into the wood. 

When sanding, you should always wear protective goggles and a dust mask. This is particularly important for pressure-treated decks as not only would you be inhaling sawdust, but potentially harmful chemicals too. 

How do you restore a weathered deck?

The first thing that you need to do is to look at the entire deck for any signs of wear or damage. Pay particular attention to areas that come in contact with the ground, as this is where moisture is likely to gather.

A good method for checking for damp is to stick a screwdriver into the wood – if it sinks then the wood must be replaced. Take this time to check for rusting screws and bolts too.

You should clean your deck at least once per year. You do not need to use a pressure washer for this if there isn’t too much grime buildup. A stiff-bristled brush, deck cleaner, and elbow grease should be sufficient. 

If you are going to apply a stain to the wood, you should fill up a sprayer with a brush attachment. Spray stain evenly across the deck surface and use a paint roller to fill in any uneven areas. 

If more repairs are needed, such as the railings, these can be done while the stain is drying. 

Before I Let You Go!

Restaining a deck is great. Washing the deck is not exactly so easy with manual scrubbing, but using pressure washer is definitely worth the time, money and effort.

In this article, I have tried my best with my personal experience to give you basic information on how to pressure wash a deck before staining. I hope if you follow my instructions, there will be no need to waste your valuable time and money.

And if you wash the deck yourself rather than a professional deck cleaner, then you have to be careful using it. This was just a brief guide, and I hope you guys enjoyed reading it.