Concrete Core Drilling in Seattle, Tacoma & Western Washington
Clean, precise round holes through reinforced concrete, from 1-inch utility penetrations to 72-inch openings, for plumbing, electrical, HVAC and structural testing. Commercial and residential, available 24/7.
30 reviews, every one five stars
Family-owned since 1999
WA Lic. SILERCC804RT · USDOT 3663541
Licensed & insured · 24/7 availability
What Is Concrete Core Drilling?
Concrete core drilling (also called concrete coring or diamond drilling) is the process of cutting perfectly round holes in concrete floors, walls and ceilings. A hollow drill bit with industrial diamonds on its cutting edge spins at high speed while the operator feeds it into the concrete by hand, with steady pressure on the handle. Out comes a solid cylindrical core, leaving a smooth, precise hole with clean edges and almost no damage to the surrounding structure.
The rig is anchored securely to the surface before the bit ever turns, so every hole lands exactly where the plans call for it, at any angle, at any height. A water-cooled core barrel keeps the bit from overheating and carries away the slurry as it cuts, which means minimal dust even when we’re drilling inside a finished, occupied building.
That precision is why coring beats jackhammering or breaking out concrete whenever a round penetration is needed. There’s no cracking, no overcut and no patching a ragged hole afterwards. The trades behind us get an opening that’s ready to use the moment we pull the core.
The extracted core itself is often the point of the job: because it comes out as a solid, intact cylinder, engineers can examine it to determine the thickness and composition of the concrete, test its compressive strength, and check for cracking, defects or deterioration, without opening up a whole slab to find out what’s inside.
Core drilling is a core part of our concrete cutting services, and Siler’s has been drilling across Seattle, Tacoma and Western Washington since 1999. If you’ve been searching for “concrete coring near me,” our crews are already dispatching in your area every day.
Why Contractors & Homeowners Choose Siler’s
Family-owned and operated since 1999.
Every one of our 30 reviews is five stars.
WA SILERCC804RT · USDOT 3663541
Nights, weekends and tight pour schedules.
What Core Drilling Is Used For
Any time a pipe, cable or duct has to pass through existing concrete (a slab, a wall, a manhole or a sewer main) or an engineer needs to see what’s inside a slab, core drilling is the right tool. These are the coring calls we take most often across the Seattle-Tacoma area, from single-hole residential jobs to hundred-penetration commercial schedules:
Plumbing & Drain Penetrations
Precise holes through slabs, foundations and walls so plumbers can run supply lines, drains and cleanouts without breaking out concrete, sized to the pipe, patched clean after install.
Electrical & Data Conduit
Clean penetrations for electrical conduit, telecom and data runs through walls and floors, drilled to spec so wire pulls go smoothly and fire-stopping seals properly.
HVAC & Mechanical Runs
Round openings for ductwork, ventilation, refrigerant lines and mechanical piping, through structural concrete without compromising the surrounding slab or wall.
Core Samples & Strength Testing
Extracted cores that engineers crush to verify compressive strength, check composition and assess deterioration, critical data for load evaluations, repairs and permits.
Anchoring Systems
Drilled anchor points that securely fasten signs, handrails, racking and machinery to concrete walls, floors and ceilings, built to hold substantial weight and stress for the long haul.
Sewer Taps, Manholes & Vaults
Tapping into sewer mains and coring through manholes and electrical vaults for new connections, precise round penetrations in precast and poured structures, with our own water and power on the truck.
Any Diameter, Any Surface, Any Angle
Our crews run core drill rigs that anchor to floors, walls or ceilings; the operator feeds the bit by hand, with steady pressure on the handle, so the hole stays true through reinforced concrete. Diamond-tipped core barrels handle holes from 1 inch all the way to 72 inches in diameter. And for smaller penetrations in tight spots, hand-held coring puts holes for plumbing, wiring and fasteners exactly where they need to be.
Every hole is water-cooled and slurry is captured with vacuum extraction, so the work area stays clean and airborne dust stays minimal. Our operators are trained on GFCI-protected, properly grounded equipment and follow strict safety protocols on every site, the same discipline in an occupied office tower as in a residential basement.
Every truck carries its own water and power, so we can drill on sites that have neither. There’s no waiting on hookups for the drilling to start.
Safety is embedded into our standard operating procedures. Crews work in hearing protection, safety goggles and respirators where dust control calls for it; work areas are barricaded with hard hats required and no one standing under an active drill hole; and every power tool runs grounded with GFCI protection, so each project is completed without incident.
Need a square or rectangular opening instead of a round one? That’s wall sawing in vertical surfaces or flat sawing in slabs. And when there’s any question about what’s buried in the concrete, GPR scanning maps rebar, conduit and post-tension cables before we drill.
Core Drilling at a Glance
Holes from 1 inch to 72 inches in diameter
Floors, walls and ceilings, any angle
Water-cooled diamond bits keep dust down indoors
Vacuum slurry recovery, clean, contained work areas
Water and power on every truck, no site utilities needed
Licensed & insured, WA Lic. SILERCC804RT
The Coring Contractor Washington GCs Call Back
Most of our core drilling is commercial: tenant improvements, new construction and infrastructure work across Western Washington. General contractors, plumbers and electricians bring us in because the holes land exactly where the drawings say, the site stays clean, and the schedule holds, including post-tension slabs that get scanned before a bit ever touches concrete.
We sequence our coring around the other trades and work occupied buildings, tight-access floors and after-hours windows. And when the job pairs coring with trenching, removal or pour-back, one call covers all of it. Recent projects where our coring and cutting crews delivered:
TI Space in Downtown Seattle
Core drilling a scanned post-tension slab for new plumbing in a downtown Seattle tenant space, no anchors and no mess, with the right tools for the job.
Ice Cream Shop TI Project
Interior trench cutting and concrete extraction to accommodate new plumbing installations. The same crews handle the coring and the cutting around it.
Fitness Quest TI Project
Cutting new trenches for plumbing with removal and pour-back for a new fitness facility in Tacoma, cut, cored, removed and restored on schedule.
Have a Job Like These?
Send us the plans or talk to the crew directly. Free estimates, 24/7 availability, one crew from first cut to haul-off.
5.0 on Google From 30 Reviews
Real reviews from Western Washington homeowners and general contractors.
“Jose big dawg was amazing. Very clean, quick. Great work cutting around a drain line”
Drew T.
Five-Star Google Review
“Their work was high quality and they were professional and communicative throughout the process. They consistently provided me with options, explained their approach, and followed through on what they said they were going to do. I would recommend them to anyone.”
Peter G.
Five-Star Google Review
“Great communication, prompt and professional work. Thank you for getting us on the schedule on short notice!”
David W.
Five-Star Google Review
How Core Drilling Works with Siler’s
A cut-only contractor leaves the break-out and the haul-off to somebody else. Siler’s cuts to your marked lines, breaks out the sections and hauls them off with one crew, so nothing falls between subs.
Free Estimate
Call (206) 901-9383 or send us the specs: hole sizes, locations and concrete thickness. We quote coring fast, and with 24/7 availability we work around your schedule.
Plan Before We Drill
When rebar, conduit or post-tension cables might be in the drill path and you want them mapped, GPR concrete scanning can be arranged before the bit touches concrete.
Drill to Spec
The rig is anchored, the bit is matched to your diameter, and the operator feeds it by hand with steady pressure on the handle, smooth, water-cooled holes with the slurry vacuumed as we go.
Cores Out, Site Clean
We extract the cores, clean the holes and haul off debris through our concrete breaking & disposal service. And if concrete needs restoring, our trench pour-back crew handles the pour-back.
Sound Familiar?
✕ An opening that’s out of square, so the frame or the duct doesn’t fit.
✕ A second sub to schedule for haul-off, and a third for the pour-back.
We built our process to take every one of these off your plate. One call. One crew. One line on your schedule.
Concrete Core Drilling Questions, Answered
Concrete Coring Across Seattle, Tacoma & Western Washington
Our core drilling crews dispatch across the Puget Sound region every day, from downtown Seattle post-tension slabs to Tacoma tenant improvements and residential basements in between, with the same equipment and the same standards on every job.
Need Precision Core Drilling?
Get a free estimate today. Tell us about the job or talk to the crew directly.