The International Association of Plumbing and Mechanical Officials (IAPMO®) has released the 2024 editions of the Uniform Solar, Hydronics and Geothermal Code® (USHGC) and Uniform Swimming Pool, Spa and Hot Tub Code® (USPSHTC), available in hardcopy and electronic formats. These editions complete a three-year consensus development cycle accredited by the American National Standards Institute (ANSI) and can be purchased through the IAPMO web store.
The 2024 USHGC provides guidelines for the installation and inspection of solar, hydronic, and geothermal energy systems, focusing on public health, safety, and welfare. Key updates from the 2021 edition include:
- New requirements for PE-RT and PEX support
- Protective barriers for energy storage systems in garages
- Guidelines for hydronic system fluids
- Expansion tanks and fluid expansion systems updates
- Material and joining methods for system piping
- Oxygen diffusion corrosion in hydronic systems
- Minimum bend radii for polyethylene pipe
- Floor surface temperature for radiant cooling systems
- Insulation requirements for radiant panels and solar thermal piping
- Geothermal system design and installation updates
- Distributed energy systems requirements
- Updated solar photovoltaic (PV) provisions
- Solar PV installation guidelines for commercial buildings
- Appendices for solar ready construction, closed-loop hydronic systems, and net zero/positive energy buildings
The 2024 USPSHTC outlines the installation and inspection of swimming pools, spas, and hot tubs to ensure their safe operation. Key updates from the 2021 edition include:
- Flood-resistant design for hazard areas
- Construction site fencing requirements
- Material standards for supply and distribution systems
- Transportation conveyor systems
- Slip-resistant surfaces for wave pools and decks
- Lighting requirements for aquatic venues
- Updates to pool finishes and surfaces
- Deck slopes and material spacing
- Disinfection and water chemistry updates
- Surge tank storage capacity
- Turnover times for equipment rooms
- Solar heaters for pools, spas, and hot tubs
- Emergency detection alarms
- Barrier and entrapment prevention updates
- New provisions for interactive water play venues, artificial water courses, float tanks, surf pools, artificial lagoons, and lazy rivers
IAPMO first introduced the USPSHTC in 1967 and the USHGC in 1976. These codes apply to the installation, alteration, and maintenance of solar energy, hydronic heating/cooling systems, and swimming pool, spa, or hot tub systems.
