Power Washing at a property in Wilmette on Lake Avenue. 800 sq ft. Completed by our Northbrook team.
— Northbrook crew
Wilmette properties along the North Shore tend to accumulate a particular kind of grime — mildew working into the grain of wood decking, black streaks bonding to brick and stone where shade and moisture do their slow work. This job covered roughly 800 square feet of outdoor surface: a wood deck and the brick and stone walkways surrounding the property. By the time we arrived, both surfaces were heavily soiled, the kind of buildup that plain pressure alone won't lift.
The walkways got a full pre-treatment before the wand touched them — specialty chemicals worked in first to break the bond on the embedded dirt and biological growth, then pressure washing, then a post-treatment to finish the job clean. The deck followed its own protocol: power washed and then post-treated with oxalic acid, which draws out the oxidation and mildew staining that settles into wood fibers over time. Working through the treatment-and-rinse sequence across all 800 square feet took patience, but the chemistry did what scrubbing alone couldn't. Invoice sent once the crew wrapped and the surfaces had been walked.
Crew on this job
Davey
Davey joined My Window Washing in 2025, but he brings more than 5 years of hands-on experience in window washing, gutter cleaning, and power washing. He’s cheerful, polite, professional, and always ready to help customers with a smile, good advice, and a can-do attitude. When he’s not making homes look cleaner and brighter, Davey enjoys creating content and checking out the latest gadgets. But honestly, who doesn’t love a good gadget these days?
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This property is served by our Northbrook office. Same-day and next-day appointments often available.
Call (847) 297-4492Showing the home's condition before our team arrived, and the result after the power washing was complete.
Before
After
Our Northbrook crew filmed this power washing on site at a property in Wilmette, IL.
You'll see the workflow across all 800 sq ft — interior and exterior approach, screen and frame detail, the rhythm of how we work through a property like this without leaving a mess.
Watch on YouTube2970 Maria Ave Suite 229, Northbrook IL 60062
Our Northbrook crew also serves these areas.
Common questions from Wilmette homeowners researching Power Washing.
This 800 sq ft deck and walkway job in Wilmette ran $935, which reflects the heavy mildew, black streaks, and the need for specialty cleaning chemicals beyond a standard rinse. For typical residential power washing in the Wilmette area, homeowners generally see prices ranging from $250 to $950+ depending on surface area, surface type, and how much buildup has accumulated.
An 800 sq ft job covering both a deck and walkways typically takes a crew two to four hours when surfaces are heavily soiled. This project required extra time because of deep-set mildew and black streaking that needed soap and specialty chemicals to fully lift before rinsing.
We treat the full surface area — in this case roughly 800 sq ft of deck boards and concrete walkways — with a pre-soak, targeted cleaning agents for stubborn staining, and a thorough pressure rinse. When mildew or black algae streaks are present, as they were here, we apply specialty chemicals to break down the growth rather than just blasting the surface and leaving residue behind.
Pressure and technique matter more than the machine itself — we adjust PSI based on the surface, using lower pressure on wood decking to clean thoroughly without splintering or raising the grain. On this job, soap and chemical pre-treatment did the heavy lifting against the mildew and black streaks, which meant we didn't need to compensate with excessive pressure that could harm the boards. For a quote, call our Northbrook team at (847) 297-4492.
Served by our Northbrook office — same and next-day appointments often available
Professional window washing, gutter cleaning & power washing across Chicago and suburbs since 2003.
