Concrete Services in Mercer Island
Mercer Island is its own city in Lake Washington, between Seattle and Bellevue. The island is almost entirely residential, with high-value housing stock that includes both mid-century mid-island homes and contemporary lakefront construction. Concrete work here leans toward decorative patios and pool decks, foundation upgrades on older homes, and retaining walls on the many slope-affected lots.
Concrete topics for Mercer Island homeowners
Popular Concrete Services in Mercer Island
Decorative finishes on premium lots
Mercer Island patio and pool-deck work frequently calls for premium decorative finishes — high-end stamped patterns, multi-color stained concrete, and exposed aggregate with specialty stone. Material and finish selection matters more here than on a typical suburban patio. See the stamped patterns guide, stained colors guide, and exposed aggregate guide for finish detail.
Slope, foundations, and shoreline
Mercer Island's terrain falls from the central plateau toward the lake on both sides. Many lots are sloped, and lakefront properties carry shoreline-buffer rules. Retaining walls, foundation repairs, and engineered drainage are recurring scopes. Mercer Island’s own geologic-hazard and shoreline rules apply to substantial work on those lots; see the permits section below.
Permits in Mercer Island
Community Planning & Development issues Mercer Island permits. Driveways and sidewalks no more than 30 inches above grade and not over a basement need no building permit. Retaining walls and rockeries up to four feet tall, measured from the bottom of the footing, are exempt only with flat ground above and below, no surcharge from a driveway, building, or fence, and on private property. Excavating or placing structures in the right-of-way requires a Right of Way Use permit.
Those exemptions do not apply in critical areas, so most work touching the ground or vegetation on a landslide, steep slope, or erosion hazard lot needs a permit, and placing a structure there requires a geotechnical report with a statement of risk. Grading and foundation work there is restricted between October 1 and April 1. Land within 200 feet of Lake Washington is shoreline jurisdiction.
Mercer Island concrete FAQs
Do I need a permit for a retaining wall on Mercer Island?
A building permit is not required for a wall four feet high or less, measured from the bottom of the footing to the top of the wall, that has flat ground on both the upper and lower sides, supports no surcharge from a driveway, building, or fence, is built on private property, and is not in a critical area. A wall that does not meet all of those conditions needs a permit.
Who reviews retaining walls and other work on steep slopes on Mercer Island?
Community Planning & Development reviews the permit. When a structure will be placed in a landslide, steep slope, seismic, or erosion hazard area, the city requires a geotechnical report prepared by a Washington State licensed geotechnical, geological, or structural engineer, and the report must include a statement of risk.
Can grading or foundation work happen in winter on a Mercer Island slope lot?
On lots with erosion, potential slide, or steep slope hazards, land clearing, grading, filling, and foundation work are restricted between October 1 and April 1. The limitation also covers land extending 10 feet past the top and toe of the slope, and a waiver requires compelling justification supported by a geotechnical evaluation.
Nearby service areas
We also pour, repair, and replace concrete in the communities around Mercer Island:
Call (206) 552-9998 for a free on-site estimate on Mercer Island.
