For Commercial HVAC Contractors
Structural Engineering for Commercial Rooftop HVAC Projects
Roof evaluations before equipment installation or replacement, multiple-unit projects, existing versus proposed operating weights, support arrangements, curbs and adapters, anchorage, reinforcement, and structural permit corrections — built for repeat contractor submissions.
Contractor document checklist
- Project address
- Existing and proposed equipment specifications
- Operating weights, if available
- Roof and equipment photographs
- Existing structural drawings, if available
- Proposed unit location and support details
- Curb or adapter information
- Permit correction notice, if applicable
Keep the form usable when some information is unavailable — "Unknown" is acceptable.
What we address
- Roof evaluations before equipment installation or replacement
- Multiple-unit replacement projects
- Existing versus proposed operating weights
- Equipment locations and support arrangements
- Roof curbs and curb adapters
- Equipment supports and anchorage
- Reinforcement when evaluation identifies a need
- Structural permit corrections
- Repeat contractor submissions
Relevant service pages
Rooftop HVAC Replacement Evaluation
A structural review for replacing rooftop air-conditioning and heating equipment, considering operating weight, location, support points, curb arrangements, and anchorage.
Multiple Rooftop Unit Replacements
Projects involving several rooftop units at one property or across multiple buildings, coordinated through equipment schedules, unit identification, and phased replacement.
Roof Load-Capacity Evaluation
A roof load evaluation assesses the existing roof framing and supports against proposed equipment or other specified roof loads to determine whether the structure can support the work.
Roof Curb and Adapter Review
Evaluation of existing curbs, replacement curbs, and curb adapters — the relationship between equipment dimensions, support locations, connections, and the underlying roof structure.
Equipment Anchorage Evaluation
Structural evaluation and design of equipment attachments, considering applicable wind and seismic forces in plain language without presenting project-specific calculations or conclusions.
Rooftop Equipment Supports
Structural support for rooftop equipment, including rails, frames, platforms, and curbs — how equipment loads transfer into the building and why support details depend on existing conditions.
Roof Reinforcement Design
Strengthening or modifying roof framing when required by engineering findings. Potential approaches depend on the building and project, and no solution is prescribed before evaluation.
Structural Engineering Letters
Project-specific engineering letters for roof and equipment evaluations. A letter documents the engineer's evaluation, findings, conditions, and limitations, and may or may not satisfy the permitting authority's requirements.
Stamped Structural Calculations
Structural calculations supporting the agreed project scope and permit submission, signed and sealed by the appropriately licensed professional. Calculations differ from a letter and from construction drawings.
Structural Permit Corrections
Reviewing and responding to structural plan-check comments from the permitting authority, preparing an appropriate engineering response within the agreed scope.
Questions before you submit? Call 714-514-4125 or email ian@blackstructural.com.