NW Structural & Shoring — Since 1974
Residential Excavation & Basement Dig-Outs in Seattle
Structural excavation is our specialty — digging under lifted and occupied homes, basement dig-outs, and tight-access work on city lots, waterfront, and hillsides across the Seattle area.
When you need this
Crawl space to basement
Turn a dirt crawl into a full-height basement — we shore or lift the house, excavate, and pour the new foundation.
Basement dig-down
Gain 12–36 inches of headroom — or go full-height with a lift — and make the space downstairs truly livable.
Tight-access sites
City lots, waterfront, and hillside properties where full-size equipment cannot go — we dig them with compact machines.
Grading & site prep
Foundation excavation, drainage-aware finish grading, and site preparation for structural work.
Why Seattle homes need it
Old houses, wet ground
Excavating under an existing Seattle home is not ordinary dirt work. The house above must stay supported at every stage, and the region’s glacial soils behave very differently wet than dry, so benching and sequencing matter as much as the machine work. Add narrow city lots, missing alleys, and grades that fall away from the street, and most excavation outfits pass on the job. This is the work we built our reputation on: structural digging planned around underpinning, shoring, and the seasons.
Our approach
We are not a dirt-moving outfit — we are a structural contractor that excavates. Dig-outs are sequenced with underpinning and shoring so the house stays supported while soil comes out from beneath it: bench by bench, section by section, to the engineer’s plan.
We size the equipment to the site, from compact machines that fit through a gate to what an open lot allows, and we finish with grading that moves water away from the new foundation instead of toward it.
How it works
1
Site visit & estimate
Free and no pressure. We walk the site, listen, and give you a straight assessment with a written estimate.
2
Engineering & permits
We handle the structural engineering and the SDCI or county paperwork so your project starts on solid footing.
3
Lift / shore / build
Our crews do the structural work — homes stay habitable during most projects.
4
Final inspection & sign-off
Work is inspected, documented, and signed off before we call the job done.
Related services
Straight Answers
Can you add a basement under an existing house?
Yes — lift or shore the house, excavate, pour a new foundation; classic crawl-to-basement conversion.
How much headroom can a dig-out add?
Typically 12–36 inches, or full-height with a lift.
Can you work on tight-access sites?
We work city lots, waterfront, and hillside sites with compact equipment.
Do you handle grading and site prep?
Yes, including drainage-aware finish grading.
Get a straight answer about your house
Free site visit, honest assessment, written estimate — often the same day you call. Ask for Jeff.