We degrease the concrete behind your kitchen

Grease builds up behind every busy kitchen

Behind a restaurant, grease comes from more than one place. The exhaust fan on the roof throws off grease the hood filters did not catch, and it runs down the wall onto the ground. Trash bags drip on the way to the dumpster. The grease bin gets topped off and some of it misses. After a few months that concrete goes dark and slick, and every pair of shoes carries some of it back through the kitchen door.

The job goes in a set order. First the loose material comes up: food scraps, flattened cardboard, and any caked grease thick enough to scrape. Then a degreaser goes down and sits long enough to break the grease loose from the concrete. Only after that does the pressure washer come out. It works in overlapping passes from the back wall toward the low side, so dirty water never crosses concrete that is already clean.

Done right, the concrete is one even color and your shoe does not stick when you step on it. When a step gets skipped, you can tell. Washing without a degreaser mostly moves grease around, and it leaves a gray film that goes black again in a few weeks. Blasting too close with a narrow tip cuts stripes into the surface, and those etched lines hold grease worse than the smooth concrete ever did.

• Caked grease and debris scraped up first
• Degreaser applied and given time to work
• Concrete pressure washed in overlapping passes
• Grease splatter washed off the back wall
• Final rinse until the water runs clear

Phoenix heat bakes grease into concrete

Summer in Phoenix does something to grease that milder places never see. The concrete behind a kitchen sits in full sun most of the afternoon and gets far hotter than the air around it. Grease on that surface thins out and soaks down into the pores. When it cools off at night it sets up again, a little deeper each time, which is why an old stain here fights back harder than a new one.

Then the monsoon arrives. Those summer storms drop a lot of water in a short time, and a greasy slab sheds its grease with the runoff. It spreads across the parking lot and into the storm drain at the curb, and storm drains are not the sewer line your kitchen sink feeds. Getting the concrete clean before storm season means less grease is sitting out back when that first heavy rain comes through.

Dust storms make it worse. When a wall of dust rolls across the valley it settles on everything, and it sticks hardest to anything greasy. What is left is a gritty crust that a quick hose-down will not touch. The grease underneath has to break down before water can lift the dust and the grease together. That is why the degreaser always goes on before the washer, never after it.

Most back door grease starts on the roof

A lot of the grease on that concrete never came out the back door. It came out of the kitchen exhaust. Air from the cook line pulls grease up through the hood and the duct to a fan on the roof. When that system is dirty, the fan throws grease across the roof, and from there it runs off the edge and down the wall to the ground below.

Most restaurants around Phoenix sit in strip centers and stand-alone pad buildings with flat roofs and block walls finished in stucco. A flat roof drains through openings in the short wall along its edge, and grease that lands on the roof follows the same path the rain does. You can often pick out a greasy kitchen from the parking lot by the dark streak running down the stucco under one of those openings.

That is why we look at the exhaust side too. Cleaning Resource Center cleans commercial kitchen exhaust hoods and systems, and we offer a free inspection. Washing the concrete while the roof fan keeps shedding grease only buys a short break before it looks the same again. One customer, Mark Moreno, wrote on Google: "Good communication left my hood spotless." Cleaning the source and the ground together is how the back of the building stays clean.

Each surface out back needs different handling

Concrete takes a pressure washer well when the tip and the distance are right. Asphalt behaves differently. It is made with oil, so a strong solvent degreaser can soften it, and a narrow tip held close can strip the top layer and loosen the stones underneath. Where a grease trail runs off the concrete onto the parking lot, that stretch gets a gentler cleaner and a wider spray pattern so the blacktop stays in one piece.

Stucco walls around the back door catch splatter from trash bags and the grease bin. Stucco is porous and textured, so high pressure up close can chip the finish coat or push water in behind it. The right way is a degreaser left to do its work first, then low pressure working from the top down. That way the dirty water never streaks across the lower part of the wall that was already cleaned.

The dumpster enclosure is usually the worst spot on the property. Block walls on three sides hold in the heat and the smell, and the gate drags through whatever is on the ground. A greasy enclosure draws flies, and it is also where your staff walk while carrying heavy bags. Spill cleanup is one of the services on our listing, so a grease bin that tipped over can be handled as its own job.