MEP Engineering and Permit Plans

What MEP covers

• Mechanical — equipment selection and sizing, load calculations, duct design and layout, ventilation and make-up air, exhaust, kitchen hoods, and equipment schedules.
• Electrical — service sizing and load calculation, panel schedules, power and lighting plans, feeders, grounding, emergency and egress lighting, and low voltage coordination.
• Plumbing — fixture counts and schedules, supply and waste layouts, riser diagrams, water heater sizing, grease waste and backflow where required.
• Energy compliance — the documentation the jurisdiction requires, prepared as part of the set rather than sourced separately at the last minute.

Coordinated, not just co-located

The most common MEP problem in a permit set is not a bad calculation. It is three sets of drawings that were produced independently and never checked against each other — a duct running through a beam, a panel located on a wall that was deleted, a fixture count that does not match the architectural.

Because the architectural, structural and MEP sheets are drawn by the same firm, that reconciliation happens before submittal rather than in a correction letter, or worse, in the field when a contractor discovers it.

Where MEP gets scrutinised

Commercial build-outs, restaurants and medical suites draw the closest MEP review. Ventilation rates, exhaust and make-up air balance, grease waste, medical gas, and electrical service capacity in an older building are the recurring flashpoints. On residential work the usual issues are simpler: service capacity for an addition, and whether the existing panel can take what is being added.