Can I Pressure Wash Inside a Garage?
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Using a pressure washer can be a very effective way to clean dirty garage floors.
Let’s start with the difference between a power washer and a pressure washer. The main difference is that a pressure washer is a cold water unit, while a power washer is a hot water unit. Power washers are heavier because of the heating coils and more expensive to rent.
A pressure washer is usually enough for just a cleaning job. Power washers are for removing surfaces or whole repaint/epoxy jobs or seriously oily garages.
Don’t use a hot water line for the pressure washer. The gaskets and seals are not designed to use with hot water temperatures.
If you are renting a pressure washer to wash a bare concrete garage floor, get a gas engine washer with a minimum rating of 3.000 PSI and a water flow rate of 3 GMP or more.
- Rental is around $40-$70 per day, depending on where you live.
Check out the most popular pressure washers at Amazon.
Electric pressure washers rarely produce more than 2,000 psi, and the job will take much more time because you’ll be pushing around a pile of dirt and debris.
Go over the washer and start it in the rental place to know how to operate it in your home. Ask for different nozzles, yellow 15° spray nozzle and green 25° nozzle at least.
How to Pressure Wash a Garage Floor
Wet down the garage floor before cleaning with the pressure washer. That can eliminate streaking that usually occurs when the concrete dries. If you have a big garage, it is best to work in sections.
- Pretreat all the grease and oil stains with a concrete degreaser(paid link). Scrub it on with a deck brush and let the stains soak for about 15 minutes.
- For best end results, you want to soak the entire floor with a degreaser as well. Many pressure washers have a separate reservoir to add a degreasing product.
- Add the degreaser to the washer reservoir and select the low-pressure settings in the machine and tip of the wand. Apply the solution to the entire floor. It should look like foamy liquid. Turn off the degreaser valve when you are done.
- If the machine doesn’t have a degreaser reservoir. Just mix up the solution in a bucket and scrub it all over the floor with a deck brush.
- Wait about 15-20 minutes for the degreaser to soak. If it’s a hot day, make sure the degreaser does not dry out. Spray some water if necessary to keep the floor wet.
- Put the yellow 15° spray nozzle on. This works well for heavy cleaning. If the floor is not very dirty, you can use the green 25° nozzle to cover a larger area but with less force.
- Start cleaning. The key is to keep the wand from 6″ -12″ from the surface while pressure washing. Keep the wand constantly moving, and don’t linger as you can accidentally etch the concrete. Use methodical patterns and make sure you don’t miss any areas. Some oily spots may need a second application of degreaser.
How Often Should I Pressure Wash My Garage?
Annually
You should, at minimum, do power cleaning of the garage and driveway once a year. This way, you keep the areas at least maintained somewhat. Depending on where you live, the site may get very grimy looking in one year. So cleaning is recommended upkeep.
Season Changes
Some countries have all four seasons. After and before winter is usually the time to perform cleaning and upkeep of the property. To prepare for winter and clean after winter.
Springtime also brings in pollen. Fall brings in dust and leaves. Winter brings in the garage snow, salt and slush. Four times a year is maybe needed in some areas to really clean the garage and driveway. Usually, two times a year is enough. Assess the situation and remove the dirt, grime, and debris as needed.
When Needed
If you just moved to a new home build area, there will be lots of construction and remodeling dust and debris in the air. Do power cleaning as often as needed depending on the construction timeline occurring in the area.
Power Washer Safety
Power washers can seriously harm you or other people. Never point the nozzle to anyone or your feet or hand. Wear rubber boots or different suitable working boots. Wear safety glasses too.
Tape off the electric outlets at least or the lower 3-4 feet of your walls with cheap plastic to protect them. Hose down your driveway before and after the job. To prevent the garage’s contaminants from drying in the pavement.
Purge the hoses and the pressure washing unit of air before starting the machine. Make also sure the unit is sitting straight. When finishing. Shut the unit and waterline and let the rest of the pressure come out of the nozzle before disassembling the waterline.
Best Way to Clean Garage Floor Without Pressure Washer
- Rent power floor scrubber/buffer. Get a concrete degreaser(paid link) cleaning liquid too.
- Shop vacuum or wet/dry vac and plain old bucket, deck brush, and a garden hose with a high-pressure nozzle.
- Mix gallon of water and a cup of baking soda for a chemical-free cleaning agent that removes stains. If you don’t like using chemicals.
- Mix TSP (Trisodium phosphate)(paid link) and water. Wear gloves and safety glasses(paid link). Pour the solution to stains and scrub. Rinse with water.
Follow the recommended instructions for the TSP or degreaser.
If the floor is very dirty or greasy and oily, it’s easiest just to rent a pressure washer for the day.
How Do You Degrease a Garage Floor?
The easiest way is with a power washer, as previously discussed in this article. Check that section.
- You can also use commercial degreasers(paid link) if the spills are not all around the floor.
- Sawdust, cornmeal, and cat litter work too with dishwasher detergent.
- If the spill is fresh, use sawdust, cornmeal, or cat litter to absorb the liquid. Leave them to suck up the liquid for about 24h hours and sweep it up.
- After sweeping, you can try dish soap or laundry detergent into the stain. Let it sit for about an hour. Pour little water and scrub the area with a nylon-bristle brush. Rinse and repeat. Finish it off with just water.
Mix TSP (Trisodium phosphate)(paid link) and water. Wear gloves and other safety equipment(paid link). Pour the solution to stains and scrub. Rinse with water.
WD-40 also removes oil stains from concrete. Get most of the oil off the first, saturate the stain with WD-40 and let it soak for about 10 minutes. Wipe off with a rag and use dish soap and water to finish it off.
Best Way to Clean Garage Floor in Winter
It is good practice to spend a little time cleaning the garage floor during the winter at least a couple of times, preferably more. It will keep your garage floors in better condition and makes future cleaning easier.
- Clean the floors with hot water and degreaser or washing solutions.
- Pick a solution that contains 70% of alcohol. It will not evaporate so fast, and you’ll have more time to work, and it does not freeze.
- Scrub the floors using a deck brush or similar tool. Remove water with a squeegee.
The salt and chemicals quickly erode bare concrete.
If your garage is not insulated or heated, you might want to wait someday when the temperature is above 32F or 0C, so the water doesn’t freeze on your floor. Consider renting or buying a portable heater, so the floor dries faster.
Sealed concrete is much easier to keep clean than bare. Consider also using plastic mats for the floor or going all in and getting an epoxy floor. Epoxy floors are straightforward to keep clean, and they will deal with anything you or winter can throw at it easily and will last years.
Best Way to Clean Garage Floor Before Epoxy
Preparing old concrete floors for epoxy can take days. Its recommended to rent a power floor scrubber/buffer or even shot blaster. Depending on the floor condition, etching may be enough. Check the epoxy floors article for more info.
Best Way to Clean an Epoxy Garage Floor
- Wiping up all stains immediately or scrubbing them off with non-caustic cleaners.
- The important thing about car spills is not allowing them to sit on the floor surface for too long.
- Don’t use any cleaning compounds with citrus or acid in them.
- Epoxy floors do not need soap! warm water, and a good mop or deck-scrubbing brush should be just fine.
- Epoxy coating can lose/change color under UV rays, so keep your garage door closed whenever possible.
Best Way to Clean Garage Floor Before Painting
Preparing old concrete floors for paint can be a lot of work if you want the paint to last. It’s recommended to rent a power floor scrubber/buffer(Special grinding heads are available for the purpose of removing mastic, paint, and sealers). or even a shot blaster. Depending on the floor condition, etching may be enough.
A power washer is an excellent option to remove paint.
- Painting the garage floors with regular floor paints is not recommended. The garage floor has to take a lot of beating, and the paint will scratch and peel off fast, and you have to repaint in a couple of years.
- If you really want to paint the floor, use very high-quality epoxy paint. Consider also an actual epoxy floor. The floor preparation process is almost the same in both cases.
- Tiles or plastic mats are a good option too for a garage.
Best Way to Clean a Painted Garage Floor
- Use low-pressure washing with a pressure washer. To avoid the paint from peeling off.
- Rent power floor scrubber/buffer. Get a degreaser cleaning liquid too.
- Shop vacuum or wet/dry vac and plain old bucket and mop or deck brush.
How to Remove Rust Stains From Concrete
Moisture and tools made of metal rust if they sit too long on the floor. Garden tools, buckets, steel rims, etc., leave rust stains. To remove rust:
- Use white vinegar or lemon juice directly to the stain and let it sit for about 15 minutes.
- Scrub with nylon-bristle brush and rinse with water.
- Rinse and repeat the process for stubborn stains.
You can also try to make a paste using laundry detergent and baking soda, and water together. Let the paste sit an hour on the stain. Scrub with brush and rinse away with water.
If the rust is sitting in and won’t budge, get and oxalic acid. You can buy it from a hardware or home improvement center. Some concrete cleaners for rust stains(paid link) have it as an ingredient. It’s also available in powder form with mixes with water. This stuff is strong, so about 5 minutes should be enough. Rinse with water.
Don’t use metal scrub brushes or steel wool to clean concrete.
How to Remove Paint Stains From Concrete
Paint drops and stains can be hard to remove if the paint is dried. Try first with a putty knife or similar to scrape off the paint and sweep the area.
Mix TSP (Trisodium phosphate) and water. Wear gloves and safety glasses. Pour the solution to stains and scrub. Rinse with water. Scrape the paint and rinse and repeat until the paint is gone. For hard to remove paint stains, you may need a paint stripper. Read the instructions and use safety glasses and gloves, and ventilate the garage well.
Best Way to Clean Oil off the Garage Floor
Oil and grease stains are inevitable in a garage. Vehicles, lawnmowers, and other equipment leak fluids. Oil stains should be cleaned right away. Especially if the garage floor is an unsealed concrete floor. Unsealed concrete has a nasty habit of sucking up any fluid quick.
- If the spill is fresh, use sawdust, cornmeal, or cat litter to absorb the liquid. Leave them to suck up the liquid for about 24h hours and sweep it up.
- After sweeping, you can try dish soap or laundry detergent into the stain. Let them sit for about an hour. Pour little water and scrub the area with a nylon-bristle brush. Rinse and repeat. Finish it off with just water.
- Mix TSP (Trisodium phosphate) and water. Wear gloves and safety glasses. Pour the solution to stains and scrub. Rinse with water.
- WD-40 also removes oil stains from concrete. Get most of the oil off the first, saturate the stain with WD-40 and let it soak for about 10 minutes. Wipe off with a rag and use dish soap and water to finish it off.
Don’t use metal scrub brushes or steel wool to clean concrete.
Best Way to Clean Old Garage Floor
This depends on which condition the concrete floor is. Are there lots of old oil stains? Use etching or power washer with degreaser. If the concrete is chipped away, you need a shot blaster or sand off a layer and resurface it.
If the floor is in bad condition. Get an expert to take a look.
- Repair minor cracks and chips with any concrete patching product.
- It is recommended to rent a power floor scrubber/buffer. (Special grinding heads are available for the purpose of removing mastic, paint, and sealers). Depending on the floor condition, etching may be enough.
Garage Cleaning Products
Soap
- Olive-oil based soap or lye-based soaps are most effective at cleaning concrete floors specifically.
- Do not use soap on epoxy floors! Soap-based floor cleaners leave overcasts on the floor that buildup on epoxy finish that causes the floor to become dangerously slippery when wet.
Deep Cleaners
- Heavy-duty products(paid link) to remove stubborn stains
Degreases
- These work well with concrete floors with oil stains. Degreasers(paid link) are non-corrosive and non-abrasive
Baking Soda
- A gallon of water and a cup of baking soda(paid link) is a natural cleaning agent for any kind of floor.
Scrubbing Towels and Wipes
- Best for cleaning spills fast and for cleaning tools(paid link) etc.
Washing Solutions
- They are another excellent cleaning agent for garage floors. Pick a solution that contains 70% of alcohol. It will not evaporate so fast, and you’ll have more time to work. Most wash solutions don’t even need rinsing with water.
Deck Broom
- Sweep broom, deck broom(paid link) with nylon heads. Brittle brush with nylon heads
TSP
Mix TSP (Trisodium phosphate)(paid link) and water. Read the instructions carefully and use protective gear.
For Oil Spills
- Sawdust, cornmeal, and cat litter work well. Sweep up and rinse with dishwasher detergent and water. WD-40 removes oil too. Oil absorbent rolls and pads(paid link) work great, absorbing any kind of liquids.
For Rust
- Oxalic acid(paid link). White vinegar or lemon juice. You can also try to make a paste using laundry detergent, baking soda, and water together.
Cleaning Products to Avoid
Ammonia
- Don’t use ammonia on concrete floors. It might break sealant if the floor has one. Ammonia also produces poisonous gas.
Bleach
- Same as ammonia. It can disintegrate garage floors and produces fumes.
High Acidic Substances
- If you use substances like citrus or vinegar. Make sure to not let them sit too long and clean them very well off after usage. It’s recommended to not use these at all at any floor type.
Cleaning Products You Should Never Mix
Bleach+Vinegar
- They produce highly toxic chlorine gas.
Baking soda+Vinegar
- You’ll just create a foamy mess.
Bleach+Ammonia.
- They produce highly toxic chloramine. Many glass and windows cleaner contains ammonia, so avoid mixing them with bleach.
Drain Cleaners
- Don’t mix two different types of drain cleaners or even use one right after another. You can create an unstable liquid that can explode.
Hydrogen Peroxide+Vinegar
- Combining these in the same container creates peracetic acid, which is toxic.
Bleach+Rubbing Alcohol
- These create toxic chloroform.
Can You Store Cleaning Products in a Garage?
A garage is a good place for cleaning products. Just put them high enough or, better yet, in cabins(paid link), so they are away from kids. It’s best to keep all the cleaning products in one place and not scattered around the house.
Suppose your garage is not heated or insulated, and the temperature goes below 32F or 0C. In that case, the garage is obviously not a good place for liquids that can freeze.
