We work with general contractors and custom builders across Bonner and Kootenai counties on new construction. The clean rough-ins are easy. The ones that delay closing are the ones where one of these items got missed in framing. Here's our short list — bookmark and share with your subs.
Gas line sizing
Tank water heaters typically draw 36,000–40,000 BTU/hr. Tankless can draw 150,000–199,000 BTU/hr — almost 5× more. Your gas main and branch lines need to be sized for total simultaneous load (water heater + furnace + range + fireplace). On most tankless installs we see, ½" gas to the unit is too small — needs ¾" minimum, often 1" depending on run length.
Venting clearances (tankless)
- Sidewall vent termination: minimum 12" above grade, 36" from any window/door, 48" from outside corner
- Concentric vent kit on tankless: most are 4" OD — frame the rough-out at 5" minimum
- Don't share venting with the furnace unless you're running a common-vent code-compliant configuration
Drain pan and floor drain
Required by code for water heaters installed in attics or above living space. Many builders forget this when the heater is in a closet over a finished basement. We'll catch it on rough inspection — but cheaper to plumb the floor drain to the sanitary line during framing than retrofit.
Recirculation loop
If your buyers want hot water at the master bath in 5 seconds (and luxury home buyers want this), a recirculation loop needs to be plumbed during rough-in. Adding it later means opening drywall — much more expensive than doing it during framing, and a frustrated homeowner either way.
Expansion tank location
Code requires a thermal expansion tank on closed systems (most municipal supplies with a backflow preventer or PRV). Spec it on the cold-water inlet to the heater. Common mistake: placing it where it can freeze in unconditioned spaces — burst tank floods the basement.
Power and circuits (electric or hybrid)
- Electric tank: dedicated 30A 240V circuit
- Hybrid heat pump: dedicated 30A 240V plus 6" clearance for airflow + drain for condensate
- Tankless gas: still needs a 120V outlet for the controller
What we'll bring to the job
Builder pricing for spec-home packages, factory-authorized installs on Navien and Rinnai, written warranty registered to the homeowner at closing, and a clean rough-in inspection ahead of the city inspector. We work to your construction schedule. See our new construction service.



