Concrete Contractor in Mercer Island, WA - Level Slabs on Sloped Lots
Allied Redmond Concrete is a concrete contractor based in Redmond, WA, and we work on Mercer Island too, pouring driveways, patios, steps, footings and retaining walls that sit level and shed water on the island's sloped lots.
- Licensed and insured.
- Free in-person estimates.
- Expect a reply within 1 business day.
Mercer Island homes sit on slopes above the lake
Mercer Island sits in Lake Washington, just across I-90 from Bellevue, and outside its small downtown it's mostly homes. Most of the calls we get here are for driveways, patios, steps and walls around houses that someone has put real money into.
The houses run from older places on big wooded lots to newer custom homes, and a lot of them are built on hillsides that drop toward the water. That makes most jobs here slope jobs. Driveways climb steeply from the street, patios get cut into the hill, and every slab has to send rain away from the house. The ground can hold water and move, so the work here starts underneath. We dig out to firm soil and build the base up before any concrete goes in.
Concrete services we offer on Mercer Island
Concrete driveway building
Steep island driveways need a base that's dug out and packed, and a broom finish whose fine ridges help tires and shoes grip in the rain.
Concrete patio construction
A patio off the back of a hillside house has to fall away from the walls, so we set the slope before we pour and rain heads downhill.
Stamped concrete services
Stamped concrete gives a patio or front walk the look of stone, pressed into a slab poured on the same packed base we'd use for plain work.
Concrete sidewalk building
Walks that step down a hillside lot need even grades and drainage, so the path from the street to your door doesn't hold puddles or ice.
Garage floor concrete
Older garage floors often crack or sink where the fill underneath settled, so we break out the slab, rebuild the base and pour a flat new floor.
Decorative concrete
Colored and textured finishes suit the island's custom homes, and we match them to the house while keeping the slab underneath built for wet, shifting ground.
Concrete retaining walls
On sloped lots a concrete retaining wall holds the hill back from a yard or driveway, with drainage behind it so water doesn't push it over.
Concrete floor installation
Basements, shops and lower levels built into the hillside get interior slabs poured flat and level over a packed base, ready for flooring or left bare.
Concrete pool decks
Pool decks are wet all summer, so we pitch them toward the drains, give them a finish with grip and cut joints where cracks should land.
Concrete steps construction
Hillside homes here tend to have plenty of steps between the street, the door and the yard, and we form each run at even heights so nobody trips.
Slab foundation building
A slab foundation for an addition, garage or outbuilding starts with firm, packed ground under it, which matters more on slopes that can shift and hold water.
Foundation installation
New foundations on hillside lots are built to the engineer's plans and the site's ground, and we pour them so the house above sits square.
Concrete parking lot building
Small commercial and multifamily lots on the island see daily traffic, so we build the base for steady loads and slope the lot so water runs to the drains.
Concrete footings
Decks, walls and additions need footings set below where the ground freezes and on firm soil, which on a slope can mean digging deeper than you'd expect.
Foundation raising
When a slab or footing has sunk on shifting hillside ground, raising it back to level can save a tear-out, once we've found out why it dropped.
Concrete cutting
Cutting lets us open an old driveway or patio for drainage, a new walk or a repair without breaking up the whole slab, which keeps the mess down.
Get a free written quote for your Mercer Island job
We get back to you within one business day to set a time, and I come out to look at the site myself. The estimate is free, with no obligation, and you get a written quote line by line.
(425) 285-8289- Mon–Fri: 7 AM–10 PM, Sat–Sun: 8 AM–9 PM
- hello@concretecontractorredmond.com
- Redmond, WA 98052
Permits, licenses and price on Mercer Island jobs
On Mercer Island, construction projects go through the city's Building Team, which checks plans against the codes the city has adopted, and a separate city team handles zoning, shoreline permits and variances. Whether your job needs a permit is the city's call. If it does, I'll tell you at the estimate and we handle the application and inspection requests, and since the review has to clear before we can set a pour date, it's usually the first thing that moves the schedule. Before you hire anyone, check that they're registered as a contractor with the state Department of Labor & Industries, and that they've added Mercer Island as an endorsement to their Washington business license, which the city requires of any business working here. We're licensed and insured.
Getting a crew and a concrete truck onto the island means planning around I-90 traffic and tight, winding streets, which is routine for a crew that pours in Redmond and up in Maltby the same month. After the permit, weather moves the schedule most, because we don't pour into a downpour. Price here turns on a few things: how much digging and base work the ground needs, how steep the site is, how far the truck has to reach, the size of the slab, how much old concrete comes out and the finish you pick. The base is where I won't cut. A fancy finish on a base that was only raked flat settles and cracks along with the dirt under it, and nobody can fix that once the truck has left, so if the budget's tight, go plain on top. The written quote puts each part on its own line, so you can see which is which.
Mercer Island slopes and rain are hard on concrete
A lot of the island's homes are built on ground that's prone to sliding, and even where the hill stays put, water runs down it and soaks the soil under driveways and patios. When the base under a slab was only raked level instead of dug out and packed, that soft fill settles, and you get sinking, cracks and water pooling against the house. We dig down to the subgrade, the firm soil a slab rests on, and pack a gravel base over it. We add rebar, the steel that holds a slab together if it cracks, where the job calls for it, and we check where the water will run before we set the forms.
Concrete shrinks as it dries, so every slab cracks somewhere. We cut control joints, shallow grooves that give that crack a straight place to happen, on pour day, and we pour early so the top doesn't dry too fast and turn dusty later. That's the straight answer to whether the new slab will crack like the old one.
What to expect when you hire us on Mercer Island
From your first call to the last sweep of the driveway, here's how a Mercer Island job runs and what you get at each step.
Call or send the form
Tell us what you want poured or replaced and roughly where on the lot, and send photos if you have them. We call back to set a time for me to come out.
I walk and measure the site
I come out myself, look at the slope and the drainage, measure and ask how you'll use the space, and it helps if you're home for it. You then get a written quote with each part on its own line, so you can see what the base costs and what the finish costs.
We set the date and permits
Once you say go, we set a date and take care of the permit side if the job needs one, and the pour waits until any review is done. Work that blocks a sidewalk or the street for the truck needs the city's Right of Way Use permit, and street work generally runs 9 am to 3:30 pm on school days.
We pour, cure and clean up
Our crew digs out, packs the base, forms, pours and finishes, and I'm on site running it from the prep to the cleanup. Then the slab cures, the wait while it gains strength before it can carry weight, and you'll be walking on it well before you can drive on it.
Questions about concrete work on Mercer Island
(425) 285-8289How much does a concrete driveway cost on Mercer Island?
A Mercer Island driveway is priced mostly by the site, not the size, because steep lots need more digging, more forming and more base work than flat ones. Breaking out and hauling the old slab, adding a retaining wall or drainage, and any permit work all add to it. I'll give you a written quote with each part on its own line after I've seen the lot.
How long does the no-grading season last on Mercer Island steep lots?
On lots the city treats as Erosion, Potential Slide or Steep Slope Hazard areas, clearing, grading, filling and foundation work aren't allowed from October 1 to April 1. The city may grant a waiver with compelling justification backed by a geotechnical evaluation of the site and the planned work. If your job falls under it, call early enough to get through any review before fall, because that's when the dig has to happen.
How do I know if my Mercer Island project needs a geotechnical report?
The city requires a geotechnical report when a proposed structure will sit in a sensitive or critical area, which includes landslide, steep slope, seismic, erosion, flood, wetland and stream hazard areas. A Washington State licensed geotechnical, geological or structural engineer signs and stamps it, and every report includes a statement of risk. Ask the city whether your lot falls in one of those areas, and tell me what you find, because I'd rather know before I write the quote.
How deep do concrete footings need to go on Mercer Island?
The city's residential code design table puts the frost line at 12 inches, so footings are usually set at least that deep to stay below where the ground freezes. The same table rates weathering here as Moderate. On a slope or soft ground the plans can call for deeper footings, and we build to whatever the approved plans say.
Do I need a permit to remove a tree for a new driveway on Mercer Island?
Most likely yes, because the city's own guidance says the answer to whether a tree permit is needed "is almost always yes." Check with the city before anyone cuts. A tree in the way of a driveway or patio is something to sort out before the quote is final, so mention it when you call.
What paperwork does a Washington contractor have to give me for a concrete job?
For any residential job of $1,000 or more, a registered Washington contractor has to give you a Model Disclosure Statement Notice to Customer. The state also requires contractors to be bonded and insured to protect the public. Get that paperwork and a written quote before anyone starts digging.
Redmond, WA
Call about your Mercer Island concrete job
We pick up until 10 PM on weekdays and 9 PM on weekends, so you can call after work and talk the job through with your photos in hand.