Updated: May 30, 2026
Location and Projects
Address
Ellicott City, MD, 21043
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Gerard David Oneill HVAC/Mechanical Contractor
Gerard David Oneill, Ellicott City, MD holds a Heating, Ventilation, Air Conditioning And Refrigeration license according to the Maryland license board.
Their BuildZoom score of 90 indicates that they are licensed or registered but we do not have additional information about them.
Their license was verified as active when we last checked. If you are thinking of hiring Gerard David Oneill, we recommend double-checking their license status with the license board and using our project planner to get competitive quotes.
Gerard David Oneill Contact Information
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This is a sample of this contractor's permits. Click here to access their complete permit history.
Project number: b00127469 single family dwelling sfd- install hvacr extend 90 days thru 2-12-05 install hvacr system
Valuation:
N/A
Permit #:
M00006610
Status:
complete
Fee:
$88
Permit Type:
N/A
Building Type:
N/A
Project number: b00152293 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00010966
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Project number: b00156105 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00010927
Status:
complete
Fee:
$182
Permit Type:
N/A
Building Type:
N/A
Project number: b00156922 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00010830
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Project number: b00156202 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00010656
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Residential hvac addition alteration permit
2005-11-22
Project number: b00155203 single family dwelling sfd- install hvacr installl hvacr system
Valuation:
N/A
Permit #:
M00010299
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Project number: b00155736 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00010300
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Residential hvac addition alteration permit
2005-11-21
Project number: b00154643 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00010287
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Project number: b00153354 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00009778
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Project number: b00151487 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00009751
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Project number: b00154332 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00009752
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Residential hvac addition alteration permit
2005-07-13
Project number: b00151180 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00009570
Status:
complete
Fee:
$138
Permit Type:
N/A
Building Type:
N/A
Project number: b00151474 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00009262
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Project number: b00151970 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00009263
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Project number: b00152595 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00009240
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Residential hvac addition alteration permit
2005-05-16
Project number: b00151462 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00009241
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Residential hvac addition alteration permit
2005-02-16
Project number: b00141650 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00008868
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Project number: b00151868 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00008869
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Project number: b00151415 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00008870
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
Project number: b00147552 single family dwelling sfd- install hvacr install hvacr system
Valuation:
N/A
Permit #:
M00008745
Status:
complete
Fee:
$94
Permit Type:
N/A
Building Type:
N/A
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Verified License
BuildZoom confirmed this contractor's license
Gerard David Oneill License info
Verified License
| License # | 6420 |
| Status | Active |
| State | Maryland |
| Type | Heating, Ventilation, Air Conditioning And Refrigeration |
- BuildZoom verified this license was active as of May 2026.
Verify this license's status for Gerard David Oneill at the Maryland Department of Labor, Licensing & Regulation.
This is a sample of licensing data; click here to access a complete history.
90
BuildZoom Score
36
Permits
- Building permit records show that Gerard David Oneill has worked on 36 permitted projects.
Gerard David Oneill Employees
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Gerard David Oneill
Owner