spray on concrete
  • Post category:Surface Cleaner
  • Post last modified:August 4, 2022
  • Reading time:4 mins read


What do you spray on concrete before pressure washing? It’s a good question, and one that I’m glad you asked. It turns out that the best thing to spray on concrete before pressure washing is not one thing but several things, in combination. Here’s what I recommend:

TSP Trisodium Phosphate.

TSP Trisodium Phosphate. This is a strong alkaline cleaner that works well on concrete and brick. It’s also good for cleaning other surfaces, like aluminum siding and vinyl siding.

Sodium Carbonate or Soda Ash

The answer to “what do you spray on concrete before pressure washing” is the cleaning agent sodium carbonate or soda ash. This chemical compound can be used to clean concrete, removing stains and other marks on the surface. It’s also used as an alkalizing agent in swimming pools, alongside chlorine.

But how does it work? The sodium ions in this compound react with free iron ions in your concrete to form insoluble iron salts that need to be scrubbed off with a brush or power washer.

Sodium carbonate is also often referred to as “washing soda” since it’s commonly added to laundry detergent, but you shouldn’t use it directly on your clothes because it can corrode fabrics like cotton shirts and denim pants – so don’t go spraying this stuff all over everything!

Oxalic acid

Oxalic acid is a weak organic acid that dissolves in water to form a clear, colorless solution.

Oxalic acid is used to clean and remove calcium and iron deposits from concrete, brick, tile and other surfaces. It can also be used in diluted solutions as a general cleaning solution for toilets and sinks. The main benefit of using oxalic acid is that it does not cause any adverse effects on your skin or eyes if you come into contact with it while cleaning the surface being treated.

Sodium Hydroxide or Caustic Soda

You can use sodium hydroxide or caustic soda to remove paint and rust from concrete, but it is not safe to use in a pressure washer. This is because it is corrosive and can cause burns. If you spray it on your driveway, the stain will remain for some time after you have washed the driveway off with water.

Sodium Metasilicate

You can use sodium metasilicate to clean concrete, brick and stone. You can also use it to clean glass, tile and wood. If you like the scent of lemons or oranges, this is your go-to cleaning agent.

Sodium metasilicate is effective at removing mold and mildew stains from hard surfaces such as concrete, brick and stone without causing harm to the surface itself (in fact it will help keep them looking good). You can also use it on leather furniture if you want a nice shine without using leather conditioner or any other product that has chemicals in them!

It’s a good idea to clean concrete before pressure washing.

It’s a good idea to clean concrete before pressure washing.

The main reason is that it will save you time and money in the long run because you won’t have to do it twice. It can also help you avoid damaging the concrete, which would make your job harder!


There are a variety of options when it comes to cleaning concrete before pressure washing. Our advice is to experiment with several different combinations until you find one that works best for your situation. Keep in mind that any cleaner that leaves a residue behind may cause problems when using pressure washers – so choose wisely!