What Architects Should Review in Plumbing Consultant Drawings by Phase
Plumbing systems often run beneath the surface, literally and figuratively. But when they’re not well coordinated, the impact is anything but hidden. Misaligned pipe routes, undersized sumps, or overlooked slab conflicts can lead to disruptive change orders, unexpected delays, and long-term performance issues.
This checklist is not about turning architects into plumbing experts. It’s about helping project teams spot issues early, ask the right questions, and ensure that plumbing designs align with architectural planning and project goals.
While every project has its own set of conditions, the following list is most applicable to commercial and institutional buildings where plumbing systems are larger in scale, more spatially complex, and more integrated with other disciplines. Use it as a flexible guide across Schematic Design, Design Development, and Construction Documents to keep systems coordinated, and construction on track. Check out our other post about: Working with MEP/FP Consultants
Schematic Design (SD) Notes
By the end of Schematic Design, plumbing layouts should be developed enough to illustrate system concepts, major equipment locations, and preliminary riser zones. Drawings should support early coordination with architecture and structure and identify major spatial or code-related constraints.
- Title Block
Confirm that plumbing drawings use the correct title block and match the architectural sheet numbering format. Ensure drawing scale and orientation are consistent with architectural backgrounds. - Code and General Notes
Review code references and confirm the applicable plumbing codes and standards are listed. Verify general notes include basic design criteria for sanitary, storm, and domestic water systems. - Floor Plans
Confirm that floor plan backgrounds align with the architectural drawings, including column grid references. Ensure plans are graphically clean, with unnecessary worksets, duplicate grids, or reference layers turned off to maintain clarity and consistency. - Risers
Confirm plumbing risers are labeled, located within appropriate shafts or chases, and align with preliminary architectural and structural plans. Identify potential structural conflicts and confirm vertical alignment with the riser diagram. - Pit Sizes
Confirm sump and ejector pump sizes are shown and coordinated with structural foundation drawings. Verify locations and depths align with architectural and structural constraints. - Plan Layouts
Ensure plumbing drawings include pipe types and preliminary sizing for major fixtures and equipment. Review for basic clarity, system continuity, and early coordination with architectural room layouts. - Incoming Services
Confirm the location and routing of incoming water, sanitary, and gas services are accurately shown. Coordinate with civil and structural drawings to avoid conflicts with foundations or underground utilities. - Pumps and Tanks
Confirm that preliminary locations and weights for plumbing pumps and tanks have been shared with the structural engineer. - Floor Drains
Verify the location and labeling of all floor drains throughout the building. Confirm each drain is tied to the riser diagram, and that the drain type is compatible with the room finish, slab condition, and intended use. - Roof Drains
Confirm roof drains are shown and appropriately spaced to handle the required drainage load. Drain types should be coordinated with the roofing system and slope, and should not be placed above electrical rooms or IDF/MDF spaces. - Riser Diagrams
Verify riser diagrams reflect the correct number of floors and include sanitary, storm, domestic water, and other piping systems. Diagrams should be clearly labeled and consistent with floor plans. - Storm Tanks
If stormwater detention or retention tanks are required, confirm preliminary location, size, and access are coordinated with the site and civil design. Review any structural or slab implications with the architectural team. - Schedules
Review that fixture and drain schedules are filled in with preliminary selections. Confirm these selections align with client standards, architectural finishes, and floor or roof systems. - Details
Confirm that key plumbing details, such as for floor drains, wall hydrants, or cleanouts, are provided and align with project requirements. Details should reflect expected construction conditions and architectural integration. - Noise and Vibration
Confirm general notes indicate that plumbing systems near noise-sensitive areas will require sound and vibration control. Typical mitigation includes acoustic pipe wrap, isolation hangers, or other methods to reduce transmitted noise from piping and equipment. - Review Outline Specs
Confirm that outline specifications or narrative descriptions are included for all major plumbing systems. The content should summarize system types, preliminary fixture selections, design criteria, and any known owner or code-driven requirements.
Design Development (DD) Notes
At the completion of Design Development, the full scope of plumbing systems must be clearly defined in the documents. While full coordination and construction-level detailing are not required at this stage, all major components, equipment, and routing that influence scope must be shown and coordinated. The drawings should reflect system intent, layout, and constraints necessary to support downstream development and pricing. All items from Schematic Design are expected to be further developed and advanced in alignment with Design Development scope.
- Clash Detection and Model Coordination
Verify all plumbing risers, mains, and under-slab infrastructure are coordinated in the BIM/Revit model. Use clash detection tools or visual checks to ensure piping avoids conflicts with beams, columns, trusses, and that shafts and chases, where shared with mechanical systems, are adequately sized with room for access. - Plan Readability and Graphic Clarity
Confirm all plumbing plans are legible, properly scaled, and clearly annotated. Plans should use a typical grey tone background to enhance readability. Piping should be accurately drawn and dimensioned, and views should be free of duplicate grids, unnecessary worksets, or visual clutter. - Floor Plans and Routing Coordination
Confirm plumbing systems, including sanitary, storm, vent, domestic cold, hot, and hot water return, are clearly shown with both horizontal piping layouts and vertical risers. All plumbing fixtures must be shown and tagged. Pipe types and sizes must be indicated, and routing must be coordinated with shafts, ceiling zones, floor penetrations, and architectural and structural drawings. Piping should be dimensioned. - Incoming/Outgoing Services
Confirm all utility connections, domestic water, gas, fire service, stormwater, and sanitary, are clearly shown and coordinated with the civil engineer. Verify connection points, routing, and service sizes are reflected consistently between plumbing and civil drawings. Verify sleeve locations and types are shown, and confirm if link seals are required at foundation penetrations. - Noise and Vibration
Confirm general notes or plan annotations identify requirements for acoustic isolation and vibration control, such as inertia bases, pipe hangers, or resilient supports where applicable. - Pit Sizes
Verify sump and ejector pump pit sizes are appropriate for their intended use and coordinated with structural requirements. Confirm pit locations, depths, slab recesses, and covers are shown and aligned with both structural and architectural drawings. - Floor Drains
Verify all required floor drains are shown, labeled, and tied to riser diagrams. Confirm compatibility with floor finishes and that trap primers and cleanout access are addressed. Ensure drain specifics are provided within the drain schedule. - Roof Drains and Overflow Coordination
Confirm roof drain layout is shown and that drain size and quantity meet code and expected rainfall. Coordinate primary and overflow drains or scuppers with roof slope, structural layout, and roofing system types. Avoid placing drains above electrical or IT spaces. Roof leaders must be dimensioned and fully documented. - Hose Bibs
Confirm type and location of all hose bibs and coordinate placement with exterior wall design. Quantities should support maintenance needs at grade and other key areas. If façade maintenance is provided, coordinate hose bibs accordingly. For freestanding hose bibs, verify placement with roofing and structural systems, and avoid creating obstructions. - Irrigation
Confirm irrigation requirements with the landscape architect. Verify that locations for irrigation mains, valves, and controller closets are shown and coordinated with the plumbing, electrical and architectural plans. - Risers
Confirm riser locations are tagged and vertically aligned through all floors. Coordinate space allocation with architectural drawings. Verify structural alignment to avoid beam conflicts at floor penetrations, and confirm shaft availability with mechanical. - Riser Diagrams
Verify riser diagrams are complete and consistent with floor plans. Diagrams should show all systems, sanitary, storm, vent, domestic water, roof leaders, and include pipe sizes, pump and tank connections, and any required pad details. Piping should be dimensioned. - Pumps and Tanks
Confirm that preliminary locations and weights for pumps and tanks have been shared with the structural engineer. Coordinate pad requirements and ensure adequate maintenance clearances are provided. - Stormwater Tanks
If stormwater detention or retention tanks are required, confirm sizing and location are coordinated with the civil engineer. Verify tank construction and support details with the structural engineer. - Schedules
Ensure schedules for plumbing fixtures, floor & roof drains, materials, pits and pads, etc. are mostly complete with specifics and correctly tagged on the floor plan and risers diagrams. Toilet fixture selections should align with client standards when applicable; otherwise, they are typically selected by the architect or interior designer. - Details
Review that typical plumbing details align with the project’s requirements. Key items include sleeves through foundations and rated walls, elevator sump pit sections, ejector pit details with cover plates, floor and roof drain installations, and pipe hangers. Additional detail types should be included as needed based on project scope and building systems. - Stormwater Pollution Prevention (SWPPP)
Coordinate with the civil or site consultant to determine if a SWPPP is required. Ensure plumbing documents reflect related stormwater infrastructure and comply with EPA/NPDES requirements and local Department of Environmental Protection (DEP) regulations where applicable. - Under Slab Plumbing
If under-slab plumbing is required, confirm routing is coordinated with structural foundations and with the civil engineer where it exits the building footprint. For buildings with interstitial structural slabs, confirm whether perforated drainage piping is required and coordinate layout and detailing with the structural engineer. Layouts should be clearly documented and cross-referenced where applicable. - Enlarged Toilet Room Plans
Confirm enlarged toilet room plans include complete fixture layouts and piping. Verify fixture placement is coordinated with partitions, accessibility clearances, and floor drainage. Ensure wall chases can accommodate fixture carriers and are coordinated to avoid conflicts with structural elements. - Foodservice and Café Areas
Confirm plumbing drawings reflect coordination with the foodservice consultant and architectural plans. All plumbing connections must be shown and tagged. If grease traps are required, verify type and location, and coordinate with architectural and structural drawings if recessed into the floor. - Outline Specifications
Confirm the outline specifications reflect all major system types, fixture selections, insulation, and installation requirements. Address any special conditions or client standards.
Construction Documents (CD) Notes
At the Construction Documents (CD) phase, plumbing drawings and specifications must reflect finalized system design, routing, and coordination. Drawings should incorporate accepted value engineering and owner input, and be fully coordinated with architectural, structural, civil, MEP, kitchen, landscape, sustainability, and acoustical consultants.
- Title Block and Formatting
Verify plumbing sheets use the correct title block, sheet numbering, and formatting consistent with the architectural set. Revision list should indicate the submission and date. - Contractual Requirements
Confirm that all plumbing system requirements outlined in Owner/Architect and Architect/Consultant agreements are incorporated into the documents. Coordinate scope language, deliverables, and performance expectations with project contracts. - Documentation Completeness
Verify that plumbing drawings and specifications are complete, legible, and fully coordinated. Confirm no missing layouts, schedules, legends, or system details. - Clash Detection and Model Coordination
Perform final clash detection in the BIM model and resolve all conflicts that cannot reasonably be deferred to contractor coordination. Address any layout shifts or system adjustments required by late-phase consultant coordination. - Review Comment Incorporation
Confirm that all plumbing-related comments from prior reviews, whether from the client, construction manager, peer reviewers, or internal QA/QC, have been addressed and incorporated into the final documentation. - Incoming/Outgoing Services
Confirm final routing and sleeve details for incoming domestic water, sanitary, storm, and gas lines. Coordinate with the civil engineer and structural team. Include sleeve types and link seal requirements if applicable. Ensure final room coordination is completed for plumbing systems such as domestic water and gas service. - Pit Sizes
Reconfirm sump and ejector pit sizes, depths, slab recesses, and covers. Confirm they align with architectural, vertical transportation, and structural drawings. - Floor Drains
Confirm floor drains are shown, labeled, and dimensioned. Ensure each is tied to a riser and coordinated with the floor finish and room planning. - Roof Drains and Overflow Coordination
Confirm all roof drains and overflow drains are shown, including size and spacing. Coordinate with roof slope, structural layout, and roofing assemblies. Confirm no drains above electrical and IT rooms. - Hose Bibs/Wall Hydrants
Confirm type and location of all hose bibs. Coordinate with façade design, roofing, and structural layout. Confirm coverage meets maintenance needs. - Riser Diagrams
Confirm final riser diagrams are consistent with floor plans and fully labeled. Include all systems, pipe sizes, roof leaders, pump and tank connections, and equipment pads. - Pumps and Tanks
Confirm pump and tank locations, pad details, and access clearances. Confirm final coordination with structural drawings and that all loads have been accounted for. - Schedules
Review final plumbing fixture and drain schedules as well as schedules for grease traps and food service (if applicable). All fixtures must be tagged and keyed to the plans. - Details
Confirm all relevant plumbing details are included. These may include sleeves, wall hydrants, roof drain assemblies, sump pits, trap primers, and rated wall penetrations. Details must reflect actual project conditions. - SWPPP Compliance
If required, reconfirm stormwater systems comply with SWPPP, EPA/NPDES, and local DEP requirements. Coordinate all requirements with the civil engineer. - Under Slab Plumbing
Confirm routing and coordination with structural and civil for all under slab piping. Identify and document perforated drainage piping or foundation penetrations. - Enlarged Toilet Room Plans
Confirm final fixture layouts, pipe routing, and carrier locations. Confirm accessibility clearances, wall chase sizing, and floor drain placement. - Foodservice and Café Areas
Confirm coordination with foodservice consultant. Verify final plumbing connections, fixture tags, and grease trap location and sizing. - Final Specifications
Confirm specifications include full project scope and system descriptions. Ensure coordination with acoustical and structural consultants is reflected. Specific sections to review include Hangers & Supports, Vibration and Seismic Control, Drinking Fountains and Water Coolers, Irrigation, Storm Drains, and both Commercial and Emergency Plumbing Fixtures.
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