CD Coordination

CD coordination represents the final and most critical coordination effort where all spatial conflicts, clearance violations, and discipline interfaces must be resolved before issuing bid documents. This intensive coordination process prevents costly field conflicts, reduces RFIs during construction, and ensures constructability of the designed systems.

Final Coordination Meetings

Final coordination meetings bring together all design disciplines to systematically review coordination status, resolve outstanding conflicts, and verify completion of coordination requirements. These meetings typically occur weekly during the final 90-100% CD phase when all systems are fully modeled or drawn and conflicts become apparent through overlay reviews or BIM clash detection.

Meeting agendas address specific building zones progressing systematically through the facility. Each meeting reviews clash detection reports, discusses resolution strategies, assigns responsibility for coordination changes, and establishes deadlines for implementation. Documentation includes meeting minutes, action item logs, and updated coordination models reflecting agreed-upon resolutions.

Clash Detection BIM

BIM-based clash detection provides automated identification of physical conflicts between building elements. Navisworks, Solibri, or similar coordination software combines federated models from all disciplines to detect hard clashes where elements physically occupy the same space, soft clashes where clearance requirements are violated, and workflow clashes where construction sequencing creates conflicts.

Clash detection runs generate reports categorizing conflicts by severity, location, and responsible disciplines. Critical clashes affecting major equipment, primary distribution mains, or structural elements receive priority resolution. Minor clashes involving small pipe branches or conduit routing may be delegated to field coordination with clear documentation of allowable tolerance. The goal is zero unresolved critical clashes before CD issuance.

Architectural Coordination Final

Final architectural coordination verifies all mechanical equipment locations, sizes, and access requirements against architectural space planning, door locations, ceiling layouts, and finish treatments. Equipment rooms must provide adequate clearances per manufacturer requirements and code-mandated service access. Roof equipment must coordinate with roofing systems, architectural screens, parapet heights, and access paths.

Ceiling coordination represents a major coordination interface where HVAC ductwork, piping, diffusers, and access panels must integrate with lighting layouts, sprinkler heads, architectural coffers, and structural depth. Reflected ceiling plans must be overlaid with mechanical plans to verify all conflicts are resolved. Access panel locations must provide maintenance access to valves, dampers, and control devices above ceilings.

Structural Coordination Final

Structural coordination addresses beam penetrations, floor penetrations, roof loading, equipment support requirements, and seismic bracing attachments. All penetrations through structural members require structural engineer review and approval. Penetration locations must avoid high-stress zones near beam connections and must comply with maximum allowable penetration sizes per structural analysis.

Large mechanical equipment including chillers, boilers, cooling towers, and air handling units create significant point loads or distributed loads requiring structural verification. Rooftop equipment weight, wind loading, and seismic forces must be coordinated with structural capacity. Hung equipment and piping require verification of ceiling or roof structure capacity to support suspended loads plus seismic forces.

Electrical Coordination Final

Electrical coordination establishes final disconnect locations, verifies panel schedule capacities, confirms conduit routing, and resolves conflicts between mechanical and electrical distribution systems. Each piece of rotating mechanical equipment requires coordinated electrical service with properly sized disconnects, motor starters, and circuit protection located per code requirements and operational needs.

Control power coordination ensures adequate power supplies for all control panels, thermostats, actuators, and sensor devices. Low voltage control wiring paths must be coordinated to avoid electromagnetic interference from power wiring. Fire alarm integration points for duct smoke detectors, fan shutdown controls, and smoke control system activation require careful coordination between mechanical and fire alarm designs.

Plumbing Coordination Final

Plumbing coordination resolves pipe crossing conflicts, verifies connection points for heating/cooling coil drains, confirms makeup water connections, and coordinates equipment drains. Hydronic piping crossings must establish clear vertical hierarchy - typically domestic water over heating/cooling distribution over sanitary/storm drainage. Slope requirements for drainage piping may conflict with mechanical piping and require careful 3D coordination.

Equipment requiring drainage including cooling coils, humidifiers, steam-to-water heat exchangers, and safety relief valves must coordinate drain routing to plumbing systems. Trap primer connections for floor drains in mechanical rooms require coordination with plumbing. Domestic water connections for humidifiers, evaporative coolers, and cooling tower makeup require pressure, capacity, and backflow prevention coordination.

Fire Protection Sprinkler Coordination

Fire protection sprinkler coordination ensures adequate sprinkler coverage, resolves conflicts between sprinkler piping and mechanical systems, and verifies clearances around sprinkler heads. NFPA 13 requires minimum clearances between sprinkler heads and obstructions. Large duct mains, cable trays, or piping may obstruct spray patterns requiring additional sprinkler heads or relocation of mechanical elements.

Mechanical equipment rooms, electrical rooms, elevator machine rooms, and other critical spaces require sprinkler coverage analysis considering unique obstruction conditions. Mechanical penthouses with rooftop equipment may require dry pipe or preaction systems. Coordination includes sprinkler head locations, pipe routing conflicts, and drain point locations for dry systems.

Fire Alarm Coordination

Fire alarm coordination addresses duct smoke detector locations, fan shutdown interfaces, smoke control system activation, and electromagnetic door hold-open releases. Duct smoke detectors must be located per NFPA 90A requirements in supply and return air systems serving multiple floors or large areas. Detector locations coordinate with duct layout, access for maintenance, and control power availability.

HVAC shutdown or activation sequences for fire alarm events require detailed coordination. Some systems shut down on alarm to prevent smoke circulation. Smoke control systems activate with specific fan operations, damper positions, and pressure relationships. Stairwell pressurization fans, elevator shaft pressurization, and vestibule pressurization systems require specialized fire alarm coordination for activation sequences and monitoring points.

Building Envelope Coordination

Building envelope coordination verifies all mechanical penetrations through exterior walls, roofs, and below-grade construction maintain weather-tightness, thermal performance, and air barrier continuity. Each penetration requires proper flashing, sealing, and firestopping per envelope design requirements. Penetration locations must avoid thermal bridges and maintain vapor barrier integrity.

Louvers for outdoor air intakes and exhaust discharge require coordination for size, location, and performance requirements. Louver locations must prevent recirculation, avoid exhaust contamination of intakes, and maintain required separation distances per code. Architectural treatment of rooftop equipment, screening requirements, and sight line analysis require coordination between mechanical and architectural teams.

Millwork Casework Coordination

Millwork and casework coordination addresses mechanical integration with laboratory casework, kitchen equipment, nurse stations, and other built-in furniture systems. Laboratory casework requires utility drops for compressed air, vacuum, natural gas, and exhaust connections. Fume hood connections represent major coordination points for exhaust ductwork, makeup air, and alarm system integration.

Kitchen equipment coordination involves extensive mechanical interfaces for grease exhaust hoods, appliance exhaust, refrigeration equipment, dishwasher drains and steam connections, and HVAC system interaction with high heat loads. Medical casework in procedure rooms, exam rooms, and patient rooms may require medical gas, vacuum, oxygen, and nitrogen coordination with mechanical designs.