Interior and exterior drainage solutions in WA, Washington move stormwater and groundwater away from your foundation before it reaches your basement, crawl space, or slab. We design and install yard drainage solutions WA homeowners rely on through the wet months, from French drains and sump pumps to foundation waterproofing. If water is pooling against the house or seeping into the basement, we diagnose the source and fix it.
Interior and exterior drainage solutions in WA, Washington is a category of waterproofing work that captures surface water, groundwater, and roof runoff and routes it away from the structure. Exterior work covers grading, French drains, downspout extensions, and foundation crack waterproofing. Interior work covers a sump pump, interior perimeter drains, vapor barrier in the crawl space, and a floor drying system for slab moisture. The goal is simple: keep the water table and storm runoff from finding a path into your building.
Western Washington gets 38 to 45 inches of rain a year, most of it between October and April, and that volume finds every weak seam in a foundation. Homeowners call us when the yard turns to standing water, when a basement drainage solutions WA setup fails during a storm, or when a crawl space stays damp for weeks. We start with a moisture meter and thermal imaging camera to trace where the water is entering, then build a drainage system installation WA Washington property owners can maintain for decades.
Every drainage project starts with a full inspection and ends with a tested system. The scope below covers what we handle in-house. If we find something outside the drainage scope, like a failed roof or a broken sewer line, we tell you before we start and quote it separately.
We walk the property, check grading and downspouts, and inspect the basement or crawl space with a moisture meter and thermal imaging camera. You get a written report of every water entry point we find and the recommended fix for each.
French drains, footing drains, downspout extensions, and regrading. We trench, lay perforated pipe in washed gravel with filter fabric, and route the discharge to a safe outlet. Linear footage and slope are specified in the written scope.
Interior perimeter drains, a sump basin and pump sized to the space, and a discharge line that carries water away from the foundation. We install battery backup where the water table is high and test the pump before we leave.
A 6-mil to 20-mil vapor barrier over crawl space soil, seams sealed, and the perimeter taped to the foundation wall. This stops ground moisture from rising into the framing and is the interior half of most crawl space drainage plans.
We inject polyurethane or epoxy into foundation cracks and seal the exterior where it is accessible. We relieve water pressure behind the wall first, because waterproofing a crack without fixing the drainage rarely holds through a wet season.
We fill and test the system, confirm the pump cycles and the discharge line flows, and show you how to test the pump monthly and flush the cleanouts each fall. You leave with a maintenance schedule and a warranty on the installation.
You call and describe the problem: water in the basement, a soggy yard, a crawl space that smells musty. We ask a few questions about the age of the house and where the water shows up, then schedule a same-day or next-day inspection. Emergency calls for active flooding get priority dispatch.
A technician walks the property with a moisture meter and thermal imaging camera, checks the grading, downspouts, and foundation, and looks inside the basement or crawl space. We map the water path and identify every entry point. The inspection takes 45 to 90 minutes depending on the size of the property.
You get a written scope that lists the drainage system installation WA Washington work: linear feet of French drain, sump pump model and capacity, vapor barrier thickness, and any foundation crack waterproofing. The price is fixed before we start. No surprises when the crew arrives.
Most residential drainage jobs take one to three days. We trench and lay perforated pipe in washed gravel, set the sump basin and pump, run the discharge line to a safe outlet, and restore the grading. Interior work includes sealing the perimeter and installing the vapor barrier. We protect floors and landscaping as we go.
We fill the system and test the pump, check the discharge line for proper slope, and confirm the basement or crawl space is dry. You get a walkthrough of what was installed, how to test the pump monthly, and what the warranty covers. We leave the site clean and haul away all debris.
You call and describe the problem: water in the basement, a soggy yard, a crawl space that smells musty. We ask a few questions about the age of the house and where the water shows up, then schedule a same-day or next-day inspection. Emergency calls for active flooding get priority dispatch.
Reads moisture content in drywall, framing, and subfloor so we know how far water has traveled and when the structure is dry.
Shows temperature differences behind walls and under floors, revealing hidden water and the path it took without opening the wall.
Measures relative humidity in the air and in materials, which tells us whether a dehumidifier is keeping up during drying.
Lets us see inside drain lines and under slabs to find blockages, collapses, and root intrusion before we dig.
The core of an interior drainage system. We size the pump to the water volume and install a basin deep enough to handle a storm surge.
Low-grain refrigerant and desiccant units that pull moisture out of framing and air after a water event, used with air movers for structural drying.
A 1950s Puyallup home flooded every November. The wall-floor joint seeped water, and the homeowner had been shop-vacuuming the floor for three seasons. Moisture readings in the baseboard were above 20 percent.
After: We installed a 70-foot interior perimeter drain and a half-horsepower sump pump with battery backup, plus downspout extensions and regrading on the wet side. The basement stayed dry through the next wet season, and moisture readings returned to normal.
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A Federal Way crawl space had bare soil, sagging insulation, and a musty smell that reached the living room. A hygrometer read 78 percent relative humidity, and the joists showed moisture above 18 percent.
After: We removed the wet insulation, installed a sealed 20-mil vapor barrier, and added a dehumidifier sized to the space. Within five days the joists read under 12 percent and the humidity dropped to 50 percent. The smell cleared.
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A South Hill yard had a 30-foot low spot that held water for a week after every storm. The grass was dead, and water was creeping toward the foundation. The homeowner had tried regrading by hand without success.
After: We installed a 55-foot French drain with a gravel trench and a pop-up emitter at a safe outlet, then regraded the low spot. The yard drained within 48 hours of the next storm, and the foundation stayed dry.
Book this service →Most drainage calls come down to a handful of patterns. Here is what we see most often and how we fix it, including interior and exterior drainage solutions for basement flooding WA homeowners call about after the first big storm.
Ask a pro →We regrade the soil to slope away from the house at a minimum 6-inch drop over 10 feet, extend downspouts, and install a French drain where grading alone will not solve it. The water gets a path away from the wall.
We install an interior perimeter drain that intercepts water at the joint and routes it to a sump pump. The pump discharges it outside, away from the foundation. This is the standard fix for basement drainage solutions WA homes need.
We lay a sealed vapor barrier over the soil, seal vents where appropriate, and add a dehumidifier sized to the cubic footage. We check the exterior drainage too, because a wet crawl space is often a yard drainage problem in disguise.
We size the pump to the water table and square footage, add a battery backup, and check the discharge line for freezing or blockage. If the basin is too small, we enlarge it. A tested pump is the last line of defense.
Most residential drainage projects in Washington run $1,800 to $8,500 in 2026, with a typical French drain and sump pump combination landing near $4,200. A single downspout extension or regrade is closer to $600. Cost depends on linear feet, soil conditions, pump capacity, and whether interior work is included. We give you a fixed price after the on-site inspection.
Licensed drainage and waterproofing contractors install them, and in Washington that means a state-licensed contractor with current L&I Registration. We handle both the exterior excavation and the interior sump and vapor barrier work, so you are not coordinating two trades. Ask any contractor for their registration number before work starts.
A typical residential installation takes one to three days. A French drain along one side of a house is usually a one-day job. A full perimeter system with a sump pump, interior drain, and vapor barrier runs two to three days. We tell you the schedule in the written scope and we stick to it.
Homeowners insurance usually covers sudden water damage from a burst pipe or supply line leak but not long-term seepage or poor grading, which is considered maintenance. If a storm or sewage backup caused the flooding, coverage may apply. We document the loss with moisture readings and photos and provide an Xactimate scope your adjuster can review.
If water is pooling against your foundation or seeping into your basement, call us today. We offer same-day inspections, fixed pricing, and 24/7 emergency response for active flooding. Our crews are licensed, insured, and bonded in Washington.
Schedule an Inspection 1234567890 →Call us any hour, any day. A live person answers and dispatches a crew, and most Fife, Puyallup, and Tacoma addresses see us within 60 minutes. If you prefer email, send the details and we will call you back fast. We inspect first and give you a written estimate before work starts.