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ANOKA COUNTY, MN
Concrete washing in Andover, MN
The one surface around your home where real pressure is the right tool.
Andover driveways, walks and patios take salt, sand, freeze-thaw and a summer of sprinkler water every year. Glass House cleans them at real pressure, through a surface cleaner rather than a wand, so the finish comes out even.
Rust and oil receive their own chemistry on request, and stripping, sanding and sealing are specialty projects Carson prices in person after testing what, if anything, is already on the slab.
HONEST EXPECTATIONS
Porous concrete may need a stronger treatment and may not return to a perfectly uniform finish. We tell you before we begin.
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Insured to $2M
Owner-operated
Based in Ham Lake
ANDOVER SPECIFICS
What concrete washing means in Andover
The local conditions that shape how Glass House approaches concrete washing in Andover, and the standards it holds to on every visit.
WATER
About 220 PPM, with summer iron
Andover's water averages about 220 PPM (parts per million) of hardness, above the 180 PPM level the USGS calls very hard. Its 2002 plant removes iron and manganese, but at peak summer demand untreated wells run and put both back into the system. When that water dries on a house, calcium stays behind as white spots on glass, and iron and manganese oxidize into orange and brown stains on siding, brick and concrete. Rust treatment on a slab lasts only after the sprinkler heads that caused it are re-aimed.
HOMES
A median home built in 1994
The median Andover home was built in 1994, and about half of all homes date from the 1990s and 2000s. After about three decades of sunlight, vinyl siding, painted trim and gutters break down at the surface into a chalky film called oxidation. Rain running over the chalk leaves streaks, and the roughened surface gives dirt and algae a better grip. Slabs that age have seen decades of freeze-thaw and salt, and we point out any scaling.
TREES
Oaks on the Anoka Sand Plain
Andover sits on the Anoka Sand Plain, where northern pin oak and bur oak are the most common oaks and the city calls oak wilt a serious problem. Emerald ash borer was first found here in 2016. Oak shade keeps roofs and siding damp, which algae and moss need, and oak leaves and catkins fill gutters each year. Ash killed by the borer turns brittle and drops limbs onto roofs and into gutters. Shaded slabs grow green film, which the pre-treatment kills before the surface cleaner lifts it.
WATER NEARBY
The Rum River and Crooked Lake
The Rum River forms Andover's western edge, Coon Creek runs through the city, and Crooked Lake lies on the Coon Rapids line. Kelsey Round Lake Park is also in Andover. Air near rivers, creeks and lakes holds more moisture, so roofs, siding and decks dry slowly after rain and dew. Algae, mildew and moss take hold on surfaces that stay damp, usually starting on the shaded north side. Slabs near water stay damp longer and green up sooner between washes.
Sources: City of Andover, Water Department; USGS, Hardness of Water; Point2Homes, Andover demographics (U.S. Census ACS 2019-2023); City of Andover, Oak Wilt; City of Andover, Emerald Ash Borer; City of Andover, Natural Resources and About Andover; Minnesota DNR, Crooked Lake.
HOW WE CLEAN CONCRETE
Even, stripe-free and safe for the slab
Concrete is not siding or shingles. It is the one surface where real pressure is correct, provided it is applied evenly and the slab is old enough to take it.
PRESSURE ON CONCRETE ONLY
When we say we never pressure wash, we mean your siding and your roof, which receive a soft wash at low pressure. Concrete is dense enough to take 2,000 to 3,500 psi, and on concrete that pressure is what cleans it properly.
01
Walk it and check its age
Every job starts with a walk-around. Carson looks for cracks, scaling, stains and existing sealer, and confirms the concrete is at least two years old. Sealed or stamped concrete receives a test corner first, so the method is proven on a spot nobody looks at.
02
Pre-treat the growth
A sodium hypochlorite pre-treatment goes on first, so organic growth is killed at the root rather than blasted around. Oil and rust are separate treatments with their own chemistry, handled on request in a fixed order: degreaser first, then the organic wash, then acid last and alone.
03
Surface cleaner, not a wand
A surface cleaner, a round housing with a spinning spray bar inside, lays down even passes at 2,000 to 3,500 psi. A bare wand leaves stripes, and any later sealer magnifies every overlap line, so the wand is kept for edges, steps and detail work.
04
Post-treat and detail the edges
A post-treatment evens out the tone across the whole slab. Curbs, steps, expansion joints and the edges along the house and lawn then receive a final rinse and detail, so the surface dries evenly from edge to edge.
05
Stay off for a few hours
Keep people and cars off cleaned areas for at least 3 hours. After sealing, the wait is up to 96 hours so the coating can cure as well as possible, and vehicles always wait longer than foot traffic, so plan around it.
FOR ANDOVER HOMES
What to know before your visit
SPRING
Wash off the winter
A spring wash takes off the salt, sand and grime winter leaves behind, and it reveals any new scaling, the flaking of the top surface, since a scaled slab should never be sealed.
SPRINKLERS
Keep rust off
Aim sprinkler heads at the lawn. Water that hits concrete leaves orange fans that trace the throw of the head, and they return after treatment until the head is moved.
PAVERS
Joint sand goes in last
On pavers, polymeric joint sand goes in only once everything is fully dry, and every grain is swept off the faces first, or it activates into a haze.
SEALING
Mind the weather
Cold nights and heavy morning dew are how a fresh seal turns milky. If a fall weather window is marginal, a sealing job is better booked for spring.
HOW PRICING WORKS
Quoted after we see the surface
YOUR CONCRETE JOB AT A GLANCE
QUOTE FIRST
Concrete washing
Quoted
Driveways, walks, patios, steps and pavers, surface cleaned
Rust or oil stain removal
Quoted
Stain-specific chemistry, on request
Stripping, sanding and sealing
In person
A 2 to 3 day project, priced by Carson in person
Concrete under 2 years old
Not yet
Pressure washing waits until the slab has cured
Builders and commercial sites
In person
Quoted in person by Carson
Every slab is different
Quote first
Concrete washing is quoted after Carson sees the surface, its age and what is on it. Stripping, sanding and sealing are priced by Carson in person, never over the phone, because the preparation and the weather window determine the job.
THE OWNER
The person who quotes your home does the work
Glass House is owned and run by Carson Brenny, with no crews, subcontractors or handoffs. He grew up in Ham Lake, went to Blaine High School and has worked full-time in exterior cleaning for six years. The person who quotes your home is the person who arrives, does the work and walks it with you at the end.
Every job receives the gentlest method that will do the work, because too much force or too strong a mix can cause damage that no cleaning undoes. Every homeowner receives a clear explanation of what is on the house, why the method was chosen and what cleaning can and cannot fix, before any money is spent.
IN CARSON'S WORDS
“It's my neighbors' homes: their biggest investment, one of the places they spend the most time, and where the people they care about most live. It's something everyone should enjoy, and I believe that.”
Carson Brenny, owner
WHAT IS INCLUDED
What concrete washing includes, and what it does not
Concrete is the one surface that receives real pressure, and even then it is controlled. A concrete wash covers the following.
INCLUDED
In every concrete wash
• Driveways, walks, patios, steps and pavers
• A pre-treatment that kills organic growth
• Even surface cleaner passes, with no wand stripes
• A post-treatment that evens out the tone
• Edges, curbs and expansion joints rinsed and detailed
NOT INCLUDED
Quoted separately, or not something we do
• Concrete under two years old, which pressure would permanently etch
• Oil, rust, iron, efflorescence, paint and graffiti stains
• Stripping, sanding and sealing, priced by Carson in person
• Repairing cracks, spalling and pitting
• A perfectly uniform finish on older, porous surfaces
EQUIPMENT AND METHODS
A surface cleaner, not a bare wand
Sodium hypochlorite and a spinning surface cleaner at 2,000 to 3,500 psi, high flow. Together they clean the surface, kill organic growth and leave an even finish without etching the concrete. Sealed or stamped concrete receives a test corner first. A heated machine is available on special request for oil, because heat thins oil and draws it out of the pores; it does not come to most jobs.
ANDOVER QUESTIONS
Concrete Washing in Andover: FAQ
Can you clean a new driveway in Andover?
Not until it is two years old. Concrete that young has not finished curing, and pressure would permanently etch the surface. Once it passes two years, it can be cleaned like any other slab. Sealing is a separate question: new concrete waits at least 28 days, and Carson prices any sealing in person.
Do you serve all of Andover?
Yes, every neighborhood in Andover. Glass House is based in Ham Lake, and Andover is part of its regular north metro service area, so there is no trip fee. Carson quotes, cleans and walks every job himself, wherever in Andover your home is.
Can you get oil stains out of my driveway?
Often, and the age of the stain decides how far. Concrete is full of tiny capillaries that draw oil down and outward, so a wash cleans the surface while oil below can rise back up as a shadow. Fresh spills usually come out completely and recent stains nearly so. Old, soaked-in stains improve substantially but may leave a shadow, and more than one application is normal.
Can you remove rust from my driveway?
Yes, with iron-specific chemistry, starting with a spot test. Bleach sets rust rather than removing it, which is why reaching for bleach usually makes the stain worse. Before treating, we make sure the sprinkler that caused it has been re-aimed, or the rust comes back. Iron left long enough bonds to the surface permanently, so the sooner it is treated, the better.
Should I seal my driveway?
Often, yes, and usually with a penetrating sealer. It soaks into the concrete instead of forming a film, so it breathes, cannot peel and holds up to freeze-thaw far better, typically lasting 7 to 10 years. Carson looks at the slab, its age and any previous sealer before recommending anything, and he prices sealing in person.
What should I do with a fresh oil spill?
Act within the first hour, because the clock matters more than the product. Cover the spill with non-clumping clay cat litter or oil-dry, grind it into the surface underfoot so it reaches the oil in the pores, leave it an hour or overnight, then sweep it up and follow with a degreaser.
