All phases
4
MEP Rough-ins
Plumbing, HVAC, electrical and low voltage race inside the walls — sequence them or pay twice.
Typical duration: 2–4 weeks
4 steps
0/22 complete
14–7 days
Plumbing Rough-in
DWV, vents, water distribution, and tub / shower sets, pressure-tested.
Plumbing
Prerequisites & handoff
- House dried in
- Framing complete
- Fixture and cabinet specs final
Critical measurements & tolerances
- Water closet rough 12" from finished wall, 15" min clear to side obstruction, 21" clear in front
- Lavatory drain at ~18"–20" AFF, supplies 20"–22" AFF unless vanity dictates otherwise
- Shower valve 42"–48" AFF, shower head 78"–80" AFF, tub spout 4"–6" above rim
- Vent within developed length limits per code table; vent stacks min 6" above roof and 10' from any openable window
- Trap arm slope 1/4" per foot; no S-traps
- Pressure test: 100 psi air or water held per local code during inspection
- Protect pipe within 1-1/4" of stud face with 16-gauge nail plates
Permits & inspection milestones
- Plumbing rough-in inspection with test held
- Gas piping pressure test
Field tips & tricks
- Set the tub and shower pan during rough — then protect it with plywood, not cardboard, for the rest of the job.
- Nail-plate everything. A drywall screw through PEX found at trim-out means opening finished walls.
- Dry-fit the vanity and toilet locations against the actual cabinet shop drawing before you glue anything.
Reference documents
View in library →- International Plumbing Code (IPC) · Code reference
- MEP Rough-in Pre-Drywall Inspection Form· Inspection form
- Uponor PEX Plumbing Design & Installation Manual · Install guide
- Schluter KERDI Shower System Installation · Install guide
- Moen Faucet & Valve Installation Instructions · Install guide
Field checklist
0 / 5 complete- DWV and vents complete
- Water lines run and manifolded
- Tub / shower pans set and protected
- Nail plates installed
- Test held, inspection passed
24–7 days
HVAC Ductwork & Equipment Rough
Load-calculated duct system, equipment platforms, flues, and refrigerant lines.
HVAC
Prerequisites & handoff
- Plumbing rough in (plumbing generally wins wall space)
- Manual J / D / S complete
Critical measurements & tolerances
- System sized from Manual J load, not rule of thumb; duct sized by Manual D
- Supply / return sizing to keep static pressure at or under equipment spec (typically 0.5" w.c. total external)
- Flexible duct pulled tight, supported every 4', no radius tighter than one duct diameter
- Return path for every closed room — door undercut, transfer grille, or jump duct
- Dryer vent max length per manufacturer (commonly 35' less 5' per 90° elbow), rigid metal only
- Combustion appliance clearances and vent terminations per listing
Permits & inspection milestones
- Mechanical rough-in inspection
- Duct leakage test (often Qn ≤ 4% of floor area)
Field tips & tricks
- Kinked flex duct is invisible after drywall and shows up as a hot bedroom forever. Walk every run with a flashlight.
- Mastic, not tape, on every joint and boot. Foil tape alone loses the duct-leakage test.
- Coordinate the return chase with the framer before drywall — a stolen chase means soffits in the finished house.
Reference documents
View in library →- International Energy Conservation Code (IECC) · Code reference
- MEP Rough-in Pre-Drywall Inspection Form· Inspection form
- ACCA Manuals J, S & D · Industry standard
Field checklist
0 / 6 complete- Manual J / D / S on file
- Trunks and branches installed and supported
- Boots sealed with mastic
- Return paths for all rooms
- Line sets and flues installed
- Rough inspection passed
34–7 days
Electrical Rough-in & Home Runs
Panel, circuits, boxes, and device locations set to code and to the lighting plan.
Electrical
Prerequisites & handoff
- Plumbing and HVAC rough (electrical routes around them)
- Lighting and appliance schedule final
Critical measurements & tolerances
- Receptacle height typically 12"–16" to box bottom; switches 42"–48" to center
- Kitchen counters: receptacle within 24" of any point along the wall line, no point more than 24" from an outlet; min two 20A small-appliance circuits
- General rooms: no point along a wall more than 6' from a receptacle; walls 2' or wider get one
- Box fill calculated; cables stapled within 8" of box and every 4-1/2'
- Bored holes centered in stud, min 1-1/4" from face or nail-plated
- AFCI protection on most living-area circuits; GFCI at kitchen, bath, laundry, garage, exterior, and within 6' of any sink
- Panel: 30" wide x 36" deep clear working space, 6'-7" headroom, breaker handles max 6'-7" AFF
- Smoke alarms in each bedroom, outside each sleeping area, each level; min 3' from supply registers and bath doors
Permits & inspection milestones
- Electrical rough-in inspection
- Service / meter release from utility
Field tips & tricks
- Walk the lighting plan with the homeowner at rough, in the actual rooms, with switch boxes nailed. Changes cost $20 now, $2,000 later.
- Set box depth for the finished wall thickness. Boxes recessed behind drywall are a code violation and a tedious fix.
- Leave a labeled 12"-tail and a plan mark-up photo of every home run. Trim-out gets twice as fast.
Reference documents
View in library →- NFPA 70 National Electrical Code — free access · Code reference
- MEP Rough-in Pre-Drywall Inspection Form· Inspection form
- Eaton Load Center & Breaker Instructions · Install guide
Field checklist
0 / 6 complete- Panel set and grounded
- Boxes set to depth and height
- Home runs pulled and labeled
- AFCI / GFCI circuits mapped
- Smoke / CO locations verified
- Rough inspection passed
42–3 days
Low Voltage, Security & Pre-wire
Data, TV, audio, cameras, doorbell, and network head-end pre-wire.
Low Voltage
Prerequisites & handoff
- Electrical rough substantially complete
- AV / network plan
Critical measurements & tolerances
- Keep low voltage min 12" parallel separation from line voltage; cross at 90° only
- Cat6 max run 295' (100 m) including patch cords
- TV outlets: box + conduit sleeve behind each display; 60"–66" AFF for wall-mounts
- Network head-end: dedicated receptacle, ventilation, and a labeled panel
Permits & inspection milestones
- Low-voltage permit where required; usually inspected with electrical rough
Field tips & tricks
- Pull a spare conduit from head-end to attic and to the media wall. Future you will pay real money for it.
- Label both ends of every cable with a printed tag before drywall. Toning 40 unlabeled drops is a lost day.
Reference documents
View in library →- MEP Rough-in Pre-Drywall Inspection Form· Inspection form
- Structured Cabling Best Practices (TIA-570) · Industry standard
Field checklist
0 / 5 complete- Data / coax pulled and labeled
- Camera and doorbell runs in
- Speaker wire and backboxes set
- Head-end location powered
- Spare conduits installed