/ Start here
What kind of problem is on the table?
Pick the problem you actually have. Hubs are grouped the way a permit set is reviewed. The next page tells you what to send.
Map of every hub: Field knowledge · screens: Field tools.
Permits, comments, Miami-Dade
I have permit comments
Send the letter, the current set, permit number, and which comments you want Masterbuild to own.
I have a comment letter
Printable response skeleton. Cite the section. Name the sheet.
I am about to upload a set
Printable checklist mapped to the field tools.
“No permit — under $7,500”
HB 803 does not exempt mechanical work. Same-amp AC still needs a mechanical permit.
The contractor wants to start before the stamp
105: exemption is not a code holiday.
Miami-Dade or Broward letter?
One Florida Building Code. Two building departments. Name the city and county.
Written building-department decision to appeal
112: the board cannot waive the code. No universal 30-day clock.
Stop Work Order on site
115: a verbal lift is not a lift.
The contractor wants to energize tomorrow
109: the utility meter-set is not the building department’s yes.
Gas and HVAC on the same M-sheet
101: fuel gas is IFGC. Confirm IMC vs IRC before the first drawing.
Existing air-handling unit “grandfathered”
102: additions meet today’s code. Occupancy change is a building-department confirmation.
Kitchen, exhaust, makeup
Kitchen / hood / makeup air
Type I vs Type II is a menu and listing question. Then 508 makeup air and 506.3.13 termination.
Makeup air missing on the M-sheets
Replacement air is part of the hood. Not dining outdoor air. Not an undercut door.
Grease outlet / wall fan comment
40 in above the roof. Dimension intakes. Wall path is special.
Dishwasher hood / Type II
507.3: Type II is not general exhaust. Lock the appliance list.
Residential-looking hood / restaurant cooking
505 vs 507. 400 cfm makeup air. Occupancy decides.
Restaurant — hood vs interceptor
Type I on mechanical and no grease path on plumbing is two comments.
Dryer duct / lint / screen
No screens. No screws. No fire damper in a dryer duct.
Lab / flammable / toxic exhaust
509: not general exhaust. Direct to outdoors. No dampers.
Process / battery / spray room exhaust
502: Table 403 is not the checklist.
Energy-recovery unit on a hood / dryer / lab exhaust
513.2: name the airstream before you recover it.
Doors whistle / exhaust-only rooms
501.4: makeup path drawn. Undercuts are not a large-offset strategy.
Ventilation and outdoor air
Enclosed garage ventilation
IMC 404 Full-On / Standby rates. Not a CO-system design.
Combustion air
Chapter 7 method check. Listings beat a volume guess.
Clinic / healthcare rooms
ASHRAE 170 / IMC 407 — not Table 403 with nicer diffusers.
Clinic / ambulatory / hospital-nursing ventilation
407: occupancy first. The office outdoor-air table is not ASHRAE 170.
Outdoor air only runs with cooling
405.1: occupied means outdoor air is on — including when the variable-air-volume (VAV) box turns down.
Outdoor-air louver faces the street
401.4: measure from the nearest edge, not the centerline.
“We have windows” — no outdoor air
402: 4% openable, on the sheet. Locked windows are not ventilation.
Return in the corridor
601: a corridor is not a duct.
Attic or crawl “ventilated per code”
406.1: openings math or 0.02 cfm/ft² + RH.
Townhouse / 3-story apartment ventilation
403.3.2: Equation 4-9, not the office outdoor-air table.
Rooftop unit counting return as outdoor air
403.2.1: recirculated air does not count toward minimum outdoor air.
Combustion-air damper
701: if it can fire with the damper closed, the design is wrong.
Electrical
Electrical recertification notice
County electrical path — not Florida’s structural milestone inspection. Send the notice you received.
Will the existing service take it?
Connected load is not demand. Continuous is 3 hours or more.
VFD short-circuit rating vs service fault current
The breaker rating is not the package short-circuit current rating (SCCR).
Disconnect needs a ladder
NEC 100: we can get to it somehow is not a design criterion.
Rooftop-unit swap “already has a ground”
NEC 100: a ground is not a neutral.
Rooftop unit over 2,000 cfm — no detector
606: combined returns count. Supervisory, not alarm, where a fire-alarm system is required.
Existing building, tenant improvement, equipment
Tenant improvement / shell
Architectural tenant-improvement set, existing mechanical/electrical/plumbing if any, photos of ceilings and mechanical rooms.
Use is changing (office → restaurant / clinic)
Occupancy change rewrites outdoor air, exhaust, plumbing, and often the service.
Existing building / due diligence
Photos of mechanical rooms, roofs, and panels plus the proposed change.
No sewer at the street
Miami-Dade OSTDS screen. Folio, use, survey, decision date.
Private well / water-service question
Record readiness, not a well design. Send the actual decision in front of you.
I need sealed MEP drawings
Address, occupancy, stage, disciplines, architectural drawings, deadline.
HVAC on an existing / odd envelope
Loads follow how the building is built. Not tons per square foot.
Loads / ESP / HRC spreadsheet
The spreadsheet is not the PE stamp. Send the coincident loads.
Plumbing was just “value-engineered”
Interceptor, isometric, existing stack, or sewer assumption.
Condensate / overflow comment
If the primary drain stops, where does the water go?
Cannot reach the unit
30×30 and the roof hatch/walkway have to be drawn.
Occupied room with no heat on the set
309: 68°F at 3 feet on the design heating day. Portable heaters do not count.
Called in — not approved
111: an inspection request is not an approval. Underground does not approve rough-in.
Equipment schedule with no load file
312: a recognized calculation procedure, not tons per square foot.
Water heater next to a garage
18 in elevation or FVIR. Vestibule where 304.3.1 triggers.
Unit closer than the listing
308: listing first. A note is not an assembly.
Fire/smoke damper comment
Name the assembly. Then pick the damper.
Flex through a rated wall
607.7: flex does not cross the rated line.
Factory-built chimney / fireplace
Listed system from appliance to termination — not a diameter.
“Existing chimney to remain”
801.18: size, passageway, cleanout, and clearance. Passing only size does not reuse it.
Old furnace out — opening still there
801.8: abandoned inlets closed by an approved method. Cap by contractor is not a detail.
Power venter on the roof
804.3: listed, gas-tight where positive, and the burner cannot fire if the exhauster is off.
Cap next to a parapet
802.5–802.6: 2 ft / 10 ft on the roof, and 5 ft from the flue collar. Passing one is not passing both.
PVC vent / oil-fired, no blocked-vent switch
801.20–801.21: plastic vent is not plumbing pipe. Oil needs a manual-reset blocked-vent switch.
Connector through the wall / ceiling
803.10.4: not through a floor or ceiling. Combustible wall needs a listed pass-through or a named table system.
Vent through the attic, no shield
802.8: No. 26 gage shield, 2 inches above the insulation. The appliance collar does not hold the vent.
Door almost hits the wall vent
802.9: 12 inches to the full leaf swing. A doorstop is not the clearance.
Decorative box around the chimney cap
805.7: listed for that specific factory-built chimney. A look-alike is not the listing.
Chimney has to miss a beam
805.4–805.5: 30 degrees from vertical, four elbows in the whole assembly. A strap is not a structural design.
Forced-draft / condensing, ordinary vent pipe
801.9: if the vent is positive, a leak pushes combustion products out. The listing has to match the pressure.
Hotter than a typical heater
805.6: flue gas above 1,000°F at the chimney entrance needs UL 959. Diameter is not the class.
Connector tight to wood
803.10.6: table starting minimums 9 / 18 / 36 inches. Labeling governs. Reductions only under 308.
Chimney through the attic, insulation coming
805.8: 26-gage or listed chimney shield, 2 inches above the insulation. Distinct from 802.8 vents.
Liner “about the same size” as the collar
801.6: check by cross-sectional area, not matching pipe sizes on the drawing.
Fireplace / wood stove on an existing chimney
801.11: solid-fuel needs a dedicated passageway. Looks unused is not dedicated.
Two floors sharing a vent shaft
801.19: appliances on different floors generally cannot share a vent. An exterior door is not the exception by itself.
“Connect to existing chimney” — no elevations
801.12–801.13: connector 12 in above the flue bottom; masonry cleanout 6 in high and 6 in below the lowest inlet.
Damper in the connector / two pipes into one chimney
803.5–803.7: no manual damper except solid-fuel. Oil automatic dampers: UL 17. Smaller connector enters higher.
Water heater / insert into a fireplace flue
801.10: listed for that flue type, noncombustible seal, still cleanable after the surround is in.
Power venter on the wall
804.3.3–804.3.4: 10 ft from lot lines and adjacent buildings; overlay openings, intakes, meters, and grade.
Condensing appliance on old masonry
801.15–801.16: liner has to match the appliance. ASTM C315, UL 1777, or approved to 1,800°F. Existing chimney to remain is not a liner.
Connector sags, runs long, or pokes into the flue
803.10: independent support, 75% horizontal length, inner-face entry, 1/4 in per foot uphill.
Second appliance into leftover chimney space
801.17: the space around a liner cannot vent another appliance. Shade approved liners. Unshaded is not a vent.
Fireplace / wood stove with a draft fan
804.3.8: UL 378, visible and audible warning, battery backup, smoke detector in the room. A fan-running light is not the sequence.
Smaller stove on a large old flue
801.7: flue area cannot exceed three times the appliance outlet. Oversizing is the failure mode.
Schedule says “galvanized” with no gage
803.8–803.9: a correct diameter with the wrong gage is still noncompliant. Medium-heat is a heavier table.
Power venter added to an existing chimney
801.14: connect on the inlet side. Discharge piping listed for positive pressure. A fan symbol is not the pressure boundary.
Power vent at the roof, near a parapet
804.3.5: review plan and section together. Height above this roof is not the whole check.
Power venter picked by CFM
804.3.6–804.3.7: no natural-draft appliance on the discharge. Size by manufacturer method, not stock CFM.
Cannot say what creates the draft
801.4–801.5: a vent that terminates outdoors but does not draft is not compliant. Chapter 8 path or an engineered basis with calculations.
Oil-fired, note only says IMC 801
801.2.1: coordinate with NFPA 31. A Type I hood is 507, not 801 venting.
Roof plan shows a vent, no cap
802.3–802.4: both manufacturer instructions. Type L needs a listed cap matched to that vent.
Note says IMC 801, schedule says gas
801.1: gas-fired appliances vent under the IFGC, not directly through Chapter 8. Confirm fuel first.
Masonry chimney only on the mechanical sheet
801.3: masonry chimneys are built per the IBC. Coordinate architecture and structure.
Chimney was swept; liner never mapped
801.18.2: cleaning is not continuity. A sweeping invoice is not a reuse decision.
Relined — clearance to framing never checked
801.18.4: a liner does not automatically fix clearance. UL 1777 reduced-clearance listing; fireblocking is separate.
One appliance off a common chimney
801.18.1: reuse is not the same size. Evaluate draft and condensation. Bigger is not automatically safer.
New equipment in front of the old cleanout
801.18.3: a chimney that passes on size can still fail reuse if the 801.13 cleanout is hidden.
Floor grille in a public restroom
603.18: air devices are not finish. Accessible balancing. No floor devices in IBC wet rooms (dwelling exception).
“Fabric duct” above a ceiling
603.17: exposed only, positive pressure only, no rated penetrations, UL 2518.
Cooling wrap meets R-value; seams open on the roof
604.11–604.12: 0.05 perm or 2-mil foil, seams sealed. Weather barrier is a second product.
Portable ladder to a rooftop unit
306.5: more than 16 ft above grade needs fixed access. No portable ladders. Receptacle per NFPA 70.
Stair fan on the toilet-exhaust riser
601.3: exit-enclosure ventilation is independent. Name which of the three arrangements is used.
No damper because “it’s sprinklered”
607.5.3: fire partitions generally need listed fire dampers. Name the exception, or show the damper.
Typical only says “F/S at rated walls”
607.5.4: smoke damper at the wall, corridor damper at the ceiling, CRD at the rated membrane. Not interchangeable.
Fire damper in the grease shaft “to be safe”
607.5.5: kitchen and dryer exhaust are prohibited-damper systems. Label the shaft type first.
Static CRD, fan stays on in a fire
607.6: a static CRD is not listed for a system that operates during a fire. Dynamic vs static is a listing question.
Fire-barrier exception used on a fire wall
607.5.1–607.5.2: fire walls and fire barriers are different. A horizontal exit also needs a listed smoke damper.
“Type I” on the schedule, listing missing
507.2: cfm per linear foot, 18 ga or 20 MSG, 18 in clearance. Field wrap cannot enclose a hood that punches the ceiling.
Right damper, nobody can reach it
607.4: 12×12 access or a removable duct section. Permanent 1/2-inch FIRE/SMOKE DAMPER label. Access cannot cut the rating.
Charbroiler under a 6-inch filter
507.2.8: UL 1046, 3.5 ft to charcoal. 45° with drip tray. NET cfm, not just total exhaust. Suppression per IBC 904.13.
Typical only says “install per manufacturer”
607.2: match the listing. Static dampers only if the fan shuts down. No MEP controls through the damper.
Wrapped before the light test
506.3: 16 ga or UL 1978. Liquid-tight welds. 500 fpm. Test (light and water) before concealment.
Schedule only says FSD
607.3: UL 555 / 555S / 555C, leakage class, 250°F, actuation. A generic tag is not a schedule.
Grease duct drawn flat
506.3.7: 2% slope (8.3% over 75 ft). Cleanouts 20 ft / 10 ft of 45° turns. 12×12, 1500°F gaskets.
Wrap only at the tight joists
506.3.11: enclose from the ceiling punch to the outlet. 1 hour min. No dampers. Rated access at each cleanout.
Hood drawn tight to the fryer
507.1.6: canopy 6 in overhang, 4 ft max lip. Noncanopy 3 ft / 1 ft setback. Cfm will not fix geometry.
Upblast with no hinge or grease drain
506.5: motor out of the airstream. Hinged fan, cable, restraint, 18 in above the roof, drain to a grease reservoir.
“No hood required” with no listing
507.1: if any appliance needs Type I, the whole hood is Type I. Exceptions only with UL 710B / 197 / 921 / 2162 or NFPA 96 on the drawings.
Type I fan with no auto-start path
507.1.1: auto-start or interlock. Sensor within 15 minutes. Capture test with smoke/steam before final. Residential used commercially is 507, not 505.
Duct in the slab, no leak test
603.8: approved for underground, or 2 in of concrete. 1/8 in per ft slope. Test before burial. Not within 4 in of earth.
Exterior duct, flood elevation only on civil
603.13: above IBC 1612 utility elevation or designed against flood. Weather-protect exterior ducts. Vehicle barriers.
One header for everything
509.4: incompatible materials cannot share a system. No common shafts with toilet/relief. No perchloric manifolding. Redundant fans.
Detector that only samples one return
606.3: NFPA 72, entire airflow (return, exhaust, relief), access for inspection. A symbol is not an installation.
Foam and PVC in the return plenum
602.3: flame spread 25 / smoke 50. UL 2043 devices. Flood-zone plenums above IBC 1612 or designed against water.
Explosion vent “by others”
510.1.5: IFC explosion control. DHA per IFC 2203.2. Relief-vent screens must release under pressure — not a bird screen.
Hydrogen in the garage, one mid-wall louver
304.5: two openings, 12 in from ceiling and floor, ≤ 850 sf. Mechanical per 502.16. Ignition below the stratification layer. Fire-marshal first.
Battery room with a transfer grille
502.3–502.5: exhaust charging areas and stationary battery rooms. Process-based, not a closet. Safety logic on the drawings.
Process stack over 600°F, kitchen-fan typical
510.2: Table 510.2 chimney. No. 10 MSG. High/medium/low lining, height, and clearance. Not a grease upblast.
Supply air in the stud bay
602.2: gypsum ≤125°F, above dew point. Stud/joist cavities cannot be supply plenums. Exterior-wall cavities cannot be plenums.
“Exhaust per code” with no MAQ check
502.8: over MAQ, ≥ 1 cfm/ft², emergency shutoff outside, no recirc. HPM shafts: no fire dampers.
CM cable and dry-pipe CPVC in the plenum
602.3: plenum-rated wiring or metal raceway. Plastic sprinkler in plenums is wet-pipe only. Discrete products: UL 2043.
Schedule filled from “1 cfm/ft²”
Sea-level check: Btuh ≈ 1.08 × CFM × ΔT, 500 × GPM × ΔT, 1 ton = 12,000 Btu/h. A thumb is not a load.
A2L swap, room note still A1
ASHRAE 34 class belongs on the schedule. 2L changes charge, ventilation, leak detection, listing. EPA 608 still applies.
Atrium exhaust labeled “smoke control”
IMC 512 is IBC 909, not Section 910. One-page narrative. Special inspection. Not TBD by contractor.
Salon with a restroom fan
502.20: inlets within 12 in of the chemicals, on whenever occupied. Do not dump into the return plenum.
Stair door will not open at design ΔP
512.6: ≥ 0.05 in. w.g. if sprinklered, limited by door force. Airflow ≤ 200 fpm toward the fire. Layer ≥ 6 ft. Duration 20 min or 1.5× egress.
High louver over the dispensers
502.1.2: bottom of openings ≤ 18 in above the floor. Gasoline sits on the slab. Hydrogen is the opposite — 304.5.
Baghouse dumps into the plant
510.1.3: recirc only with 99.9% at 10 µm, <25% LFL, and a continuous vapor monitor. Else outdoors. No cyclone to a firebox.
Smoke-control fan on a normal circuit
512.10–512.12: leak test 1.5× / ≤5%. Standby power in a 1-hour room. UPS 15 min. UL 864 as smoke-control equipment.
Vent running through the return plenum
601.4: fitting above the ceiling is not an approved plenum path.
Wall-vent copied from another job
804: name the category before you copy the clearance.
Schedule is listed, detail is blank
301: listed is not installed. Springs without snubbers.
I am not sure yet
The checklist by job type. A share link plus the actual question is enough to start.
Spanish start: empezar aquí · Spanish intake: enviar antecedentes · qué enviar · herramientas de campo.
If none of those fit
Location, stage, and the actual question. That is enough for a first reply.
Send Project Background+1 (786) 398-6940 · osmany.portal@masterbuildconsulting.com
Masterbuild provides engineering services under a written scope. Nothing on this page is project-specific engineering advice, a code interpretation for your project, or a representation about permit approval.