12 unit apartment building needs a AE firm.12 unit apartment building is commercial building, not residential.Especially when you are wanting to go vertical construction.You need architect, mechanical PE, structural PE, electrical PE, civil PE, and geotech.
Budget $20k minimum for an AE firm.You need to first verify site condition.Are there wetlands, protected areas?Add 6 months plus and more funding to do an EIS.
Someone mentioned a 4000 sq ft footprint.Get the architect to do a real quick basic design.The architect can then do an estimate on live and dead load.Then do a boring on site with the geotech to make sure the soil condition can support the building.If you are lucky, no special site prep is required.If soil condition isn’t ideal, then prepare to spend money on driving piles or other types of site prep to support the building.
Once you have these basic information, then you know you have a technically feasible 12 apartment building.A couple days of feasibility study won’t cut it.
The geotech information will be given to civil engineer and structural engineer.They will design the proper foundation.Structural engineer will design the load bearing structures.I personally like steel beam construction and concrete but they are more expensive.Civil and structural will work to design to seismic codes.
Mechanical engineer will do the plumbing and HVAC.Buildings need to breathe or they’ll rot from within.Electrical engineer will design the power distribution with appropriate protection circuits.Mechanical engineer will need to spend time to research and work on sewer connection to city or county sewer lines.If design requires digging up a public road for a tie in, it’s on your dime.There is a basic connection charge to tie in your sewer line.
Check with city of Bellevue on which IBC they are using.