Building Codes
Building Codes | Tankless Water Heater Install | Plumbing | Blaine
When you’re ready to swap bulky, outdated equipment for hot water on-demand, HEP’s licensed plumbers in Blaine make the transition seamless. We coordinate with local inspectors, pull the correct permits, and follow every nuance of city and state building codes, so your tankless water heater install meets the highest safety and efficiency standards. From calculating gas line sizes to setting vent clearances in tight utility closets, we sweat the technical details while you look forward to endless hot showers and lower utility bills.
Homeowners appreciate how quickly our team works—often completing installations in a single visit—and how neatly we leave each workspace behind. Because tankless units last up to twice as long as traditional tanks, you’ll enjoy peace of mind along with reclaimed square footage. Let HEP handle the paperwork, precision piping, and post-install inspection; all you have to do is turn on the tap and enjoy the comfort of limitless, energy-smart hot water.
FAQs
1. Do I need a plumbing permit to replace a conventional water heater with a tankless unit in Blaine?
Yes. The City of Blaine treats the replacement or first-time installation of any water heater—including tankless models—as an "alteration" to the plumbing system under Section 301 of the 2021 Uniform Plumbing Code (UPC). A plumbing permit must be obtained before any work begins, even if the job is performed by a licensed contractor. If fuel gas piping, venting, or electrical work is added or modified, separate mechanical and electrical permits may also be required. Permit applications can be filed online through Blaine’s ePermitting portal or in person at Community Development, 435 Martin Street, Suite 3000.
2. Which plumbing and mechanical codes does Blaine enforce for tankless water heater installations?
Blaine adopts the Washington State Building Code, which currently consists of the 2021 editions (effective July 1, 2023) of the following: • Uniform Plumbing Code (UPC) with Washington amendments • International Residential Code (IRC) Chapters 12–24 for mechanical systems • International Mechanical Code (IMC) for non-residential work • International Fuel Gas Code (IFGC) for fuel-gas provisions not covered in the UPC. Manufacturers’ installation instructions also carry code weight per UPC §314.1, so the unit must be installed exactly as listed and labeled.
3. What venting and combustion-air rules apply to gas tankless water heaters in Blaine?
Gas tankless units must be Category III or IV appliances listed for sealed combustion and direct venting. Under UPC §509 and IFGC §503: • Vent materials must be those specified by the manufacturer (usually stainless steel or special PVC/CPVC). • Horizontal terminations must clear finished grade by at least 12 in. and be 3 ft from property lines, windows, doors, or mechanical air intakes unless the listing allows closer spacing. • Intake and exhaust terminations cannot be located under decks or porches unless the listing specifically allows it. • The required combustion-air volume is generally built into the concentric direct-vent design, but if a unit uses room air, the mechanical room must meet the IRC’s 1 ft³ per 1,000 Btu/hr rule or be provided with engineered make-up air.
4. How should I size and run the gas piping for a high-BTU tankless water heater under Blaine codes?
Many tankless models draw 160,000–199,000 Btu/hr, far more than a tank-type heater. UPC Chapter 12 and IFGC Chapter 4 require you to size piping for the full BTU load at the appliance AND any downstream loads. In Blaine: • Natural gas piping is sized for a minimum 0.3 in. w.c. pressure drop (Table 1215.2(1) in the UPC). • In most houses this means a ¾-in. CSST or black iron main and a dedicated ¾-in. branch to the tankless unit. • If the run exceeds about 30 ft (straight-pipe equivalent), you may need to upsize to 1 in. • An accessible drip leg and shutoff valve within 6 ft of the unit are mandatory. • All CSST must be bonded with a #6 AWG copper wire per UPC §1211.
5. Are electrical modifications or dedicated circuits required for electric or gas tankless units?
Gas units need a 120-V, 15- or 20-amp grounded receptacle within 3 ft for the ignition and control board; this outlet cannot be on the same circuit as a sump, GFCI, or AFCI-protected bathroom receptacle. Electric tankless heaters draw 40–150 amps each leg and usually require two to four 40- to 60-amp, 240-V breakers and conductors sized #6–#2 AWG copper. Blaine follows the 2020 National Electrical Code (NEC) with WA amendments, so: • Conductors must be copper THHN/THWN rated 75 °C minimum. • A lockable disconnect within sight of the heater is required if the breaker is not visible. • If installed in a bathroom or laundry area, the receptacle or branch circuit must have GFCI protection (NEC 210.8). Any new circuits must be shown on the electrical permit application and panel load calculations.
6. What inspections are required and how do I schedule them with the City of Blaine?
A typical tankless installation calls for two inspections: 1) Rough-in (before covering piping/wiring) and 2) Final. For same-day service, requests must be made before 4 PM the previous business day through the MyBuildingPermit.com portal or by calling the Inspection Hotline at 360-332-8311, option 3. Ensure the following are ready: • Permit card and approved plans on site. • Gas pressure test (10 psi for 15 min with a 0.1 psi gauge) on rough-in. • Vent and combustion-air terminations completed. • Unit energized and operable for final; hot-water delivery must reach at least 110 °F at the nearest fixture. The inspector will also verify seismic bracing, clearances, and discharge piping for the relief valve (if applicable). Once the final passes, the permit is closed and you may insulate or conceal any remaining piping.