Contractors active in Maryland county permit records, grouped from public filings. Counts reflect permits attributed to each firm. Not every filing names a contractor, so counts here are a floor. A firm's actual permit activity is usually higher.
| Contractor | Trade | Counties | Permits | Last active |
|---|---|---|---|---|
| CONSTELLATION HOME | HVAC | Frederick County, Howard County | 363 | Jul 2026 |
| ERIC SMOCK HEATING & A/C INC | HVAC | Frederick County | 56 | Jul 2026 |
| MICHAEL AND SON SERVICES, INC. | HVAC | Frederick County, Howard County | 23 | Jul 2026 |
| UNITED AIR TEMP | HVAC | Frederick County, Howard County | 23 | Jul 2026 |
| TRI-STATE HOME SERVICES | HVAC | Frederick County | 21 | Jul 2026 |
| PUTMAN PLUMBING INC | HVAC | Frederick County | 19 | Jul 2026 |
| LARRY & SONS INC | HVAC | Frederick County | 15 | Jul 2026 |
| Tuckers Air Conditioning, Heating and Plumbing | HVAC | Frederick County | 15 | Jul 2026 |
| F.H. FURR PLMB, HTG, & A/C | HVAC | Frederick County | 14 | Jul 2026 |
| WESLEY BARR | HVAC | Frederick County | 13 | Jul 2026 |
| BRICK STREET CONSTRUCTION, LLC | HVAC | Frederick County | 12 | Jun 2026 |
| MCCREA EQUIPMENT COMPANY | HVAC | Frederick County | 7 | Jul 2026 |
| N.E. BOB WALTZ PLUMB/HTG-JEFF | HVAC | Frederick County | 7 | Jul 2026 |
| AMERICAN RESIDENTIAL SERVICES | HVAC | Frederick County | 6 | Jul 2026 |
| ANTHONY W PETROLLE | HVAC | Frederick County | 5 | Jul 2026 |
| Bradley L Gracey | HVAC | Frederick County | 3 | Jun 2026 |
Source: county permit records. Updated monthly.