Slab Installation

Expert Concrete Slab Installation in Bellingham, WA

Concrete slabs form the foundation of countless residential and commercial projects throughout Whatcom County, from ADU foundations that help address Bellingham's housing shortage to heavy-duty RV pads built to withstand our region's glacial till soil conditions. With over 15 years of slab installation experience in Bellingham and surrounding areas, we understand the unique challenges posed by our marine climate, high water table conditions, and the specific building codes enforced by the City of Bellingham and Whatcom County.

RV Pads & Heavy Equipment Slabs for Bellingham's Outdoor Culture

Bellingham residents embrace the Pacific Northwest outdoor lifestyle, which means significant investment in RVs, boats, and recreational equipment. Our community's proximity to the North Cascades, Canadian border, and countless camping destinations makes RV ownership particularly popular in neighborhoods like Cordata, Meridian, and Birchwood. However, standard concrete slabs aren't sufficient for vehicles weighing 15,000-30,000 pounds.

We engineer RV pads specifically for Bellingham's soil conditions, which include glacial till deposits and clay layers that can shift with our high annual rainfall. A proper RV pad installation in Whatcom County requires:

6-8 inch reinforced concrete thickness with fiber mesh or rebar grid for load distribution
Compacted crushed rock base minimum 6 inches to prevent settling in our wet soils
Proper drainage slope (minimum 1/8 inch per foot) to handle Bellingham's 40+ inches of annual precipitation
Perimeter drainage integration to redirect water away from the pad and foundation
Utility hookups positioned for water, electrical, and sewer connections

Recent RV pad project in Cordata: We installed a 14'x45' reinforced concrete pad for a client with a 35-foot Class A motorhome. The site had challenging drainage due to the neighborhood's relatively flat topography. We excavated 16 inches deep, installed a French drain system along the upslope side, placed 8 inches of compacted crushed rock, and poured a 6-inch fiber-reinforced slab with wire mesh. The finished pad includes a dedicated 30-amp electrical hookup and water connection, with a gentle slope directing runoff toward the street.

ADU Foundations: Meeting Bellingham's New Housing Standards

Bellingham's 2023 ADU (Accessory Dwelling Unit) code updates have made it easier for homeowners to add rental units, in-law quarters, or home offices on their properties. Neighborhoods like South Hill, Lettered Streets, and Fairhaven have seen significant ADU development as property owners respond to our community's housing shortage. Most ADU designs require slab-on-grade foundations, which are cost-effective and appropriate for Bellingham's mild climate.

Our ADU foundation slabs meet all City of Bellingham building code requirements, including:

Minimum 4-inch slab thickness with #3 rebar grid on 18-inch centers
Perimeter frost footing extending 18 inches below grade (Bellingham's frost depth requirement)
Vapor barrier installation (6-mil polyethylene minimum) to prevent moisture intrusion
Proper sub-slab insulation (R-10 minimum) as required by Washington State energy code
Embedded utility conduits for plumbing, electrical, and HVAC rough-ins
Anchor bolts properly spaced for wall plate attachment

South Hill ADU project example: We completed a 640-square-foot slab foundation for a detached ADU on a sloping lot near Sehome High School. The site required significant excavation and retaining wall installation to create a level building pad. We coordinated with the homeowner's architect to ensure proper placement of plumbing stub-outs for the bathroom and kitchen, installed rigid foam insulation per energy code requirements, and poured the slab with integrated radiant floor heating tubing. The project received full approval from City of Bellingham inspectors on first review.

Garage Slabs: Handling Whatcom County's Challenging Soils

Garage floor slabs in Bellingham face unique stresses. They must support vehicle loads, resist impacts from dropped tools and equipment, and withstand the constant moisture tracked in during our eight-month rainy season. Many older Bellingham homes in neighborhoods like York, Alabama Hill, and Samish have detached garages with deteriorating concrete floors that need replacement.

Our garage slab installations address common Whatcom County soil challenges:

Glacial till stabilization: We remove unsuitable organic topsoil and establish a proper crushed rock base
High water table management: Perimeter drainage and vapor barrier systems prevent groundwater intrusion
Clay layer mitigation: Proper base preparation prevents differential settling that causes cracks
Rocky subgrade preparation: In foothills neighborhoods near Lake Whatcom, we carefully grade and compact rocky soils

A well-designed garage slab for Bellingham conditions includes 5-6 inches of concrete over a compacted aggregate base, reinforced with fiber mesh or wire mesh, with control joints strategically placed to control cracking. We typically slope the slab toward the door opening at 1/8 inch per foot to facilitate drainage and make cleanup easier.

Meridian neighborhood project: We replaced a 50-year-old garage slab that had settled and cracked severely due to inadequate base preparation. After removing the old concrete, we discovered the original installation had been poured directly on native clay with no aggregate base. We excavated an additional 8 inches, installed perimeter drainage connected to the existing system, placed and compacted 6 inches of crushed rock, added a 6-mil vapor barrier, and poured a 5-inch fiber-reinforced slab. The homeowner now has a level, properly draining garage floor that will last decades.

Hot Tub & Spa Pads: Engineered for Pacific Northwest Conditions

Hot tub ownership is popular throughout Bellingham—there's nothing quite like soaking in 100-degree water while watching snow fall on Mount Baker. However, a filled hot tub can weigh 4,000-6,000 pounds, requiring a properly engineered concrete pad. Our rainy climate adds complexity, as poor drainage can cause settling and create standing water around the tub.

Our hot tub pad installations include:

Load calculations based on specific tub dimensions and water capacity
Minimum 4-inch thickness with reinforcement appropriate to the load
Slightly elevated design to prevent water pooling
Perimeter drainage to handle splash-out and rain runoff
Electrical conduit placement coordinated with GFCI requirements
Textured finish for slip resistance when wet

We also install pads for swim spas, exercise pools, and above-ground pools throughout Whatcom County. Each installation is customized to the equipment specifications and site conditions.

Shed & Outbuilding Foundations Throughout Whatcom County

From garden sheds in Fairhaven to large workshops in Sudden Valley, outbuildings need proper foundations to prevent settling, keep structures level, and protect contents from moisture. While some small sheds can be placed on gravel or pavers, any structure over 120 square feet or containing valuable equipment deserves a concrete slab foundation.

Our shed foundation services include both monolithic slabs (where the footing and slab are poured together) and slab-on-grade designs with separate perimeter footings. For Bellingham's climate and soils, we recommend:

4-inch minimum slab thickness for standard storage sheds
Perimeter thickening or frost footing for permanent structures
Proper site drainage to direct water away from the foundation
Anchor bolt installation for securing wall plates
Smooth trowel finish for easy cleaning and maintenance

Commercial & Industrial Slabs: Meeting Business Needs

We also install commercial concrete slabs for businesses throughout Bellingham and Whatcom County, from equipment pads at Guide Meridian industrial sites to warehouse expansions near the Bellingham International Airport. Commercial projects require coordination with engineers, compliance with commercial building codes, and often more complex reinforcement schedules.

Our commercial slab experience includes equipment pads for HVAC units, transformer pads for electrical service, loading dock approaches, warehouse floors, and retail storefront extensions. We work directly with commercial contractors, property managers, and business owners to meet project schedules and budget requirements.

Why Proper Slab Installation Matters in Bellingham

Concrete slab failure is common in Whatcom County when installations don't account for our specific conditions. We regularly see slabs that have settled due to inadequate base preparation, cracked from freeze-thaw cycles without proper reinforcement, or developed moisture problems from missing vapor barriers. A properly installed slab should last 30-50 years or more with minimal maintenance.

Our installation process includes:

Site evaluation and soil assessment before providing estimates
Proper excavation depth to remove unsuitable soils
Aggregate base installation and compaction using appropriate materials
Drainage system integration when needed for site conditions
Vapor barrier placement to prevent ground moisture intrusion
Appropriate reinforcement (fiber mesh, wire mesh, or rebar) based on load requirements
Quality concrete mix designed for Whatcom County weather exposure
Proper finishing and curing to maximize strength and durability

Serving All of Bellingham & Whatcom County

We install concrete slabs throughout Bellingham's neighborhoods—from Fairhaven's historic district to Cordata's newer developments, from lakefront properties on Lake Whatcom to rural acreages in Ferndale and Lynden. Our crews are familiar with the varying soil conditions, drainage challenges, and permit requirements throughout Whatcom County.

Every slab installation includes our standard warranty covering workmanship and materials. We're fully licensed and insured in Washington State, with L&I contractor registration and liability coverage. Our team coordinates permit applications with the City of Bellingham or Whatcom County when required, and we work with inspectors to ensure full code compliance.

Ready to discuss your concrete slab project? Whether you're planning an ADU foundation in the Lettered Streets, need an RV pad in Birchwood, or want to replace a failing garage floor in York, we'll provide a detailed estimate and realistic timeline. Contact us today to schedule a site evaluation and receive a written proposal for your Bellingham-area slab installation project.

Ready to get started? Contact us today for a free estimate — we serve all of Bellingham and Whatcom County.