Excavation Contractor in Markham, ON
OCM Excavation & Construction is the excavation contractor Markham homeowners and builders call when the job has to be right. We dig foundations, prep lots, grade properties, trench utilities, and drill post holes across Markham — Unionville, Cornell, Cathedraltown, Berczy, Box Grove, Markham Village. 35 years of experience, fully licensed, WSIB-certified, $5M insured. Call 416-317-3090 for a free site walk this week.
What We Excavate in Markham
- Basement & foundation excavation — new builds, underpins, walkout conversions.
- Site preparation for custom home builders along 16th, Major Mac, and Elgin Mills East.
- Land grading and drainage correction — common fix in 1990s Markham subdivisions.
- Trenching for water-service upgrades, sewer replacements, gas, hydro, and weeping tile.
- Post hole drilling for decks, fences, and pergolas — sonotubes to 4 feet for frost.
- Mini excavator work — for Unionville Heritage District homes where wide machines are restricted.
How Much Does Excavation Cost in Markham?
A standard basement excavation in Markham typically runs $5,000 to $13,000. Trenching for a 1-inch water service upgrade averages $4,500 to $9,000. Backyard grading is usually $2,500 to $6,500. Pool digs run $8,000 to $17,000. We quote everything in writing after a site visit — no “starting at” guesses.
Why Markham Customers Pick OCM
We’re local to the area and respect Markham’s heritage districts and tree bylaws. We pull our own utility locates, carry full liability and WSIB, and we’ve never missed a final grading inspection in Markham. Most of our work comes from referrals.
Frequently Asked Questions
Do I need a permit for excavation in Markham?
Yes for foundations, pools, additions, and most retaining walls. Heritage district properties in Unionville may also need heritage approval.
How long does site preparation take in Markham?
2 to 5 days for a standard residential lot. Add 1 to 2 days if soil testing or excess soil characterization is required for infill builds.
Can you handle Markham’s tree protection bylaw?
Yes. We install protection fencing, avoid root zones, and coordinate with the city arborist when required.
Do you remove old underground oil tanks in Markham?
Yes. We coordinate with TSSA-registered partners for tank removal and handle contaminated-soil excavation and disposal.
How quickly can you start a Markham project?
Most Markham jobs start within 1 to 3 weeks of signed quote. Call 416-317-3090 to check current scheduling.
Free Markham Excavation Quote
Call 416-317-3090 or request a written estimate. Real number, real timeline, real contractor.
Our Excavation Services
Excavation Services · Site Preparation · Land Grading · Trenching & Post Drilling · Mini Excavator · Pool Excavation
Wondering what your project will cost? Read our 2026 excavation cost guide for the GTA — real numbers, no fluff.