If you want to know how to pressure wash a deck before staining, then this step by step guide will show you exactly how to do it without gouging massive holes or leaving deep marks etched into your deck…

First things first…

Pressure washing your wood deck is so easy…

Don’t worry about it!!

You see all the horror stories about a homeowner etching deep marks and gouging huge holes from not knowing how to pressure wash a wood deck, but this isn’t going to be you…

Look, it does happen and it’s easy to mess up, but you’ll be fine…

In fact, you’ll be more than fine now you’ve got this guide in your hands…

You can definitely do this…

Once you have the right pressure washer set up, and you know the “Secret Techniques” behind pressure washing a deck, it really is as easy as pointing and pulling the trigger…

You got this…

Let’s get into the good stuff shall we??

This is the Equipment You’ll Need to Pressure Wash Your Deck Before Staining…

1. Pressure washer
2. Pressure washer nozzles
3. Garden hose
4. Petrol or Electrical cable
5. Gumboots
6. Earmuffs 
7. Safety goggles
8. Deck scrub brush
9. Bucket for brightener
10. Rags

Some of the equipment you need is pretty self explanatory so I’m not going to get into all of that…

But I will help you to choose the right pressure washer and nozzles for the job…

Sound good?

Ok, but first we also need to list out the material you’ll need…

You’ll need these materials to pressure wash a wood deck properly…

1. Deck brightener…

That really is it…

You’ll need a good quality deck brightener to prepare your deck to be stained…

You can get a premixed deck brightener like this…

You still have to dilute it with water but most of the time, this is the best option for most decks…

But sometimes you might need a stronger mix of oxalic acid for those stubborn stains, so I recommend getting this product…

You can mix your own and control the strength by using a pure oxalic acid like this one…

Either way, you don’t want mould and contaminants messing up your finished deck stain, so make sure you get yourself a deck brightener…

But we also need to make sure we have the right pressure cleaner for the job…

Choosing the right Pressure Washer…

When it comes to pressure washing a deck, it doesn’t matter too much which pressure washer you use…

A cheap electric one or a high end petrol pressure washer are both perfect for cleaning a deck…

But there is a huge difference in the price and also the speed at which they remove mould and contaminants for your deck…

I’ll give a quick overview of both

Electric Pressure Washer

I’ve used a cheap electric pressure washer like this Karcher k2 and it does the job…

The Karcher k2 pressure washer isn’t as powerful as the petrol ones so it does take longer to pressure wash your deck, but less pressure makes it easier to wash without damaging your deck…

I found that if you want to simply pressure wash your deck before you stain just so it’s clean and ready to stain, the normal pressure wand that your electric pressure washer comes with is perfect for the job…

You won’t need a turbo head if you are simply washing your deck…

You’ll only need the turbo head if you want to strip your deck…

The deck brightener will actually do most of the work to clean your deck, not the pressure washer…

So it doesn’t really matter which brand you purchase but I would make sure that you have options to get other wand attachments like a turbo head…

Petrol Pressure Washer…

You only need a maximum of 1200 psi to pressure wash your deck before staining and most petrol pressure washers will give you this level of pressure…

So you won’t need to get the most powerful pressure washer on the market…

A petrol pressure washer like this would do just fine…

The Raptor RGPW3000 is around $500 dollars and a powerful 3000psi which is “heavy duty” enough to clean your deck and do it fast…

But it’s also not a commercial pressure washer so it won’t set you back a couple thousand dollars…

It’s perfect for pressure washing a wood deck…

The main concern is which pressure washer nozzle you use…

I’ve found that when cleaning a deck to remove stains, mould and greying, a 40 degree nozzle is perfect for the job…

The 40 degree nozzle is the white one…

You’d use a green 25 degree nozzle when you want a little more pressure to remove old deck stain…

Obviously it is much easier to damage your deck with a more powerful pressure washer so it is important that you use the right technique…

And that is exactly what I’m about to show you…

How to Pressure Wash a Deck Step by Step…

1. Remove furniture and sweep debris from the deck
2. Rinse deck and scrub with brightener
3. Pressure wash deck with 45 degree nozzle
4. Allow to dry for 24 to 48 hours
5. Light sand
6. Time for staining

These are the basic steps to pressure washing a deck before staining but I’ll go into more detail on each step for you now…

1. Remove furniture and sweep debris from the deck…

Obviously you want your deck to be completely clear so you can pressure wash without trying to work around furniture and pot plants…

So after we remove all of the furniture from your deck, make sure you give it a sweep off…

Of course when you pressure clean a deck, all of the debris will be blasted off but you never know where the debris will go…

You can easily get a pebble to the eye if you don’t sweep your deck before pressure washing, but the choice is yours…

2. Rinse deck and scrub with brightener…

The brightener is great for removing grease, grime and mould from your deck…

And of course you don’t want any of those contaminants on your deck before you stain it…

If you’re staining bare timber, the brightener will bring the natural colour back into your deck and open the surface ready for the stain…

Here’s what you need to do…

Mix the brightener in a buck with water and follow the instructions on the container…

You always apply the brightener to a wet deck, so you need to rinse the deck down until it’s all completely wet and scrub it with the deck brightener using your deck brush…

Allow the brightener to sit on the deck for 20 minutes, making sure you spray a light mist on it so it doesn’t dry into the surface of the deck…

3. Pressure wash deck with 40 degree nozzle…

After the brighter one has been sitting for 20 minutes, now it’s time to pressure wash your deck…

Remember that we’ll be pressure washing our deck with the 40 degree nozzle which is usually the white nozzle…

If you have an electric pressure washer, just use the wand that it comes with…

Before you start up your pressure washer, make sure you have water connected to it and then pull the trigger…

You’ll hear a lot of air coming out through the end of the pressure wand…

Hold the trigger until all of the air has come out…

Now you can turn the pressure washer on…

Make sure you always have water running to your washer while it’s turned on or you will blow your engine…

And don’t leave the engine running for more than 3 minutes without pulling the trigger…

This is another way that you’ll burn out your power washer…

Ok, now for the technique of pressure washing a deck…

Just so you get comfortable that you aren’t going to damage your deck, it’s a good idea to start pressure washing on a step before you wash your deck…

A step is much easier to replace if you damage it…

Now what you want to do is, hold the tip of the pressure washer about 30 cm away from the surface of your deck and then pull the trigger…

But don’t keep the pressure washer in one spot…

Move it along the length of the deck boards and raise it further from the surface as you reach the end of each stroke and then move it back down the board repeating the process…

See this is roughly 30 cm from the deck surface…

And this is how I raise the tip higher as I reach the end of a stroke…

Then I bring the tip back down to roughly 30 cm on the next stroke…

A stroke is how far you can reach before having to move so you can reach the next section…

If you just stop at the end of each stroke, you will get lap marks…

Now just keep going like this until you have pressure washed you entire deck

4. Allow the deck to dry for 24 to 48 hours…

It’s very important that after you pressure wash a wood deck, you leave it to dry for at least 24 to 48 hours before staining…

It’s a bad idea to stain a deck that is wet or damp…

The stain won’t absorb into the surface of the deck properly and it will look blotchy…

The moisture will also get trapped under the surface of your deck stain and cause it to peel and fade much quicker that it should…

So make sure you allow your deck to dry properly before staining…

If you need to stain straight away, there are some ways you can speed up the drying process but it’s usually best to wait 24 hours if you can…

5. Light sand…

If you are pressure washing a deck that has been completely stripped back, then you’ll need to give it a light sand after you pressure wash it but before you stain it…

You see, when you pressure wash a wood deck, you can damage the surface of the deck and you’ll get raised fibres that will look fuzzy on the surface…

You’ll need to sand those raised fibres off with an orbital sander and 80 grit sandpaper…

For a full breakdown of how to sand your deck to get it ready to stain, you should read my guide The Homeowners Guide to “How to Sand a Deck”…

Now, if you’ve pressure washed a deck that is already stained, then you won’t need to sand your deck…

Lucky you…

You can move onto the next step…

6. Time for staining…

You did it…

You successfully pressure washed your deck and now it’s ready for staining…

Of course, this brings a whole other set of techniques to learn and decisions to make…

Like, what stain should I use?

Is water based better than oil based stain??

How do you stain a deck???

Hang on a moment!!

You asked me how to pressure wash a deck before staining and that’s exactly what I showed you!!

Didn’t I??

You only get one main question per article…

Capish??

Don’t look at me like that!!

Ok… I guess I could show you how to stain our deck too…

Ahhh, you twisted my arm…

Ok, ok… click on the blue text if you want to know how to stain a deck…

I’ve put together a complete, “Do it Yourself” guide to staining your decking…

What are you still doing here?

You should be clicking that link above…

Now you know How to Pressure Wash your deck before staining, What’s next??

Well, if you follow that link above, you should have gone to a guide that shows you how to coat your decking…

That’s the next step…

And then I would save this guide and come back here  1 year from now when it’s time to wash and recoat your deck with a maintenance coat…

You’ll follow the same pressure washing process of scrubbing with a brightener and pressure washing with the same nozzle…

Then obviously follow up with 1 coat of deck stain…

That’s pretty much the process of keeping your deck looking great for the next few years…

So I think I’ll leave it right here…

I hope you feel confident enough to get yourself a pressure washer and give your deck a clean…

Remember that if you mess it up, you can always fix it…

It’s not the end of the world…

Or even the end of your deck…

So follow along and you’ll do great…

If you have any questions, feel free to leave a comment below and I’ll do my best to give you an answer…

Well, that’s my time…

Peace,

Jason – The Deck Pressure Washing Expert…

FAQ’s