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Local business · Mendon, MALocal business · PO Box 430, Mendon, MA
Verified record
J.J. Mechanical Services is a Mendon heating and sheet-metal contractor. Its Massachusetts HVAC licence, 9650-SM-M1, held by John J Knox, is active on the state registry. BBB lists John Knox as owner and a business start date of 1994, and BuildZoom shows 30 permitted HVAC and sheet-metal projects concentrated in Newton, Brookline and nearby towns.
Specializes in
Typical Greater Boston range for this kind of work, from regional averages — not a quote from J.J. Mechanical Services. Use it to sanity-check bids, then get the real number in writing.
Estimated range
$5,000 – $11,400
Typical HVAC project around $8,200
Service area
Languages
No changes recorded yet — last scanned Aug 3, 2026.
Handles complex retrofits5.0
Diagnoses before replacing5.0
Licensed plumber4.6
Named technicians4.7
