Snohomish · King · Skagit · Pierce
Retaining Walls Built to Last
Block and rock retaining walls that hold back sloped yards and driveways, built on a compacted base with drainage behind them.
What Makes a Retaining Wall Last
A retaining wall holds back soil so a slope can become a usable yard, a driveway can be widened, or a building pad can sit level. Done right, it disappears into the landscape for decades. Done wrong, it leans, bulges and fails, usually after a wet winter.
Most wall failures come down to two things: what is under the wall and what is behind it. A wall needs a compacted base that will not settle, and drainage behind it so water cannot build up pressure. In the wet Pacific Northwest, water behind a wall is the number one cause of failure.
DirtRaptor builds block and rock retaining walls and handles the whole job: excavation, base prep, drainage, the wall itself, backfill and compaction, and hauling the extra soil away on our own trucks. Taller walls, and walls holding up a driveway or slope, typically need engineering and a permit, and we build to the approved plan.
Worth Knowing
In many jurisdictions, retaining walls taller than about four feet, or walls supporting a driveway, building or slope, need an engineered design and a permit. Shorter landscape walls usually do not. The rule depends on your city or county, so confirm before building.
The Process
How a Retaining Wall Job Runs
The parts you cannot see once the wall is finished are the parts that matter most.
Plan & Permit
We measure the slope, confirm the wall height and what it supports, and flag whether engineering or a permit is needed.
Excavate & Build the Base
We dig out for the wall and build a compacted base so the first course sits level and will not settle.
Build With Drainage
The wall goes up with drain rock and a drain pipe behind it so water cannot build pressure against the wall.
Backfill & Finish Grade
Backfill is placed and compacted in lifts, and the ground above and below is graded to shed water.
Scope
What Retaining Wall Work Covers
From a short garden wall to a wall that turns a slope into usable yard.
Block Retaining Walls
Segmental block walls for clean lines around yards, patios and driveways.
Rock & Boulder Walls
Natural rock walls that fit wooded and rural properties.
Wall Drainage
Drain rock and pipe behind the wall so water never builds up pressure.
Excavation & Base Prep
Digging, leveling and compacting the base the wall sits on.
Backfill & Compaction
Backfill placed in compacted lifts so the soil behind the wall stays put.
Old Wall Removal
Failing timber, block or rock walls removed and hauled before the new one goes in.
Why Us
Why DirtRaptor for Retaining Wall Contractor
Owner On The Machine
You talk to the person doing the work, not a salesperson who has never seen your site.
Arborist-Led Tree Work
Trees and dirt work handled by one company on one mobilisation — rare in this trade.
Our Own Trucks
Haul-off is not a marked-up subcontractor line. It is a truck we own and a schedule we control.
Since 2019
Years of Pacific Northwest ground, wet seasons, and county permit desks.
Honest Exclusions
Rock, groundwater and buried debris are excluded in writing, not discovered as a surprise invoice.
Free On-Site Quotes
A real number from a real site walk, not a range guessed over the phone.
Pricing
What Drives Retaining Wall Cost
Wall cost is driven by height, length, material and what the wall has to hold back.
Height & Length
Taller walls need more material, more excavation and often engineering. Length multiplies everything.
Material
Block, rock and boulder walls differ in material cost, weight and the time it takes to set each course.
Access & Soil
Tight access, rocky ground or poor soil that has to be replaced add time and material.
The fastest route to an accurate number is a site walk. Quotes are free and there is no obligation.
Get My Free QuoteQuestions
Frequently Asked Questions
Do I need a permit for a retaining wall?
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Walls over about four feet, or walls supporting a driveway, building or slope, usually need engineering and a permit. Shorter landscape walls usually do not. We confirm with your city or county before building.
Why do retaining walls fail?
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Most fail because of water pressure behind the wall or a base that settles. Proper drainage and a compacted base prevent both.
What kind of retaining walls do you build?
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Block and rock retaining walls, including the excavation, base, drainage, backfill and haul-off.
Can you replace an old leaning wall?
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Yes. We remove and haul the old wall, fix the base and drainage that caused the problem, and build the new wall in its place.
How long does a retaining wall take to build?
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A typical residential wall takes a few days to a couple of weeks depending on length, height, access and whether engineering is involved. We give a realistic window with the quote.
Do you build retaining walls in King County?
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Yes, across north King County including Bothell, Kenmore, Kirkland, Woodinville, Redmond and Bellevue.
Can you build a wall on a steep slope?
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Often, with the right engineering. Steep and landslide-prone slopes usually need a geotechnical review, and we build to the approved design.
Question not answered here? Send us the details and we will come back to you.
Often Booked Together
Related Services
Combining scopes on one mobilisation is almost always cheaper than booking them separately.
Grading & Drainage
Retaining walls, RV and equipment pads, and drainage correction that actually moves water away from the structure.
French Drain Installation
French drains and curtain drains that collect water before it reaches the house and carry it to an approved outlet.
Excavation Contractor
Foundation pits, footings, trenching, utilities, construction roads and building pads — dug to spec, inspected, and signed off.
Across the Region
Retaining Walls Across the Region
Sloped lots are everywhere in this region, from the bluffs of Edmonds, Mukilteo and Woodway to the hillsides of Kirkland, Kenmore, Bothell and Bellevue. Retaining walls turn those slopes into usable yard, parking and patio space.
Wet winters are hard on walls, so drainage behind the wall is non-negotiable. On mapped steep slopes and landslide hazard areas, walls often need a geotechnical review in addition to engineering, and we build to the approved plan.
Where we do retaining wall contractor
In Snohomish County: Everett, Lynnwood, Bothell, Mill Creek, Mountlake Terrace, Edmonds, Mukilteo, Marysville, Snohomish, Lake Stevens, Monroe, Arlington, Brier, plus Stanwood, Granite Falls, Sultan, Gold Bar, Woodway.
In King County: Woodinville, Kenmore, Kirkland, Redmond, Bellevue, Shoreline, Lake Forest Park, Sammamish, Duvall, Seattle, plus Issaquah, Snoqualmie, North Bend, Carnation, Renton, Newcastle, Mercer Island.
In Skagit County: Mount Vernon, Burlington, Sedro-Woolley, Anacortes.
In Pierce County: Tacoma, Puyallup, Bonney Lake, Gig Harbor.
Retaining Wall Contractor Across Four Counties
Serving Snohomish, King, Skagit and Pierce County, Washington. Send photos and a rough scope and we will come back with a real number.
