Phius Chief Building Scientist Graham Wright details some of the changes that were made to the Phius REVIVE 2024 document following the public comment period.
The Phius REVIVE 2024 standard was developed and brought to fruition by the Phius technical staff, but not without guidance from our passionate community.
We received 548 comments on the public review draft of REVIVE 2024, from 13 different commenters. All of these have been responded to individually, with each commenter receiving individualized responses to their own questions. In this blog, I will highlight some of the more significant changes to the standard document, and note some of the ways Phius will practice the role of Authority in our project certification program.
Throughout the Phius REVIVE 2024 standard document, an effort was made to more clearly differentiate general versus residential versus nonresidential requirements, and to put these in a consistent order.
There has been some renumbering as the result of (for example) promoting Design from being part of the Investigation to being a whole phase of the commissioning (Cx) process in its own right, and adding a General Resilience section in addition to Winter and Summer Resilience.
Section 2.3
The size of additions within the scope is reduced from 100% of the existing floor area to 20%.
Section 6.2.1
A post-retrofit air-tightness requirement is imposed, aligned with IECC 2021.
Section 6.3.1, 6.4.1
Batteries are not strictly required - a tier “B” was added on which the electrical operation during the outage does not have to be decarbonized. Winter thermal resilience still does though. And there is a requirement for battery-readiness and photovoltaic-readiness.
Section 6.5
The “connected criteria” are dropped for heat pumps and heat pump water heaters, due to few products being available.
Section 6.5.2
Electrification (in normal operation) is required by the final retrofit phase, but not in the first phase. (Early electrification is possible but that increases the risk that people never get around to the envelope). The “B” tier does not have to do off-site renewables to get to net zero.
Section 7
No monitoring is required for residential projects.
The minimum requirement for nonresidential is to monitor energy use via utility meter readings (no additional equipment) via Energy Star Portfolio Manager. Single-family buildings are technically within the scope of Portfolio Manager, but there was reluctance to put this requirement on retrofit projects when it isn’t required for new construction. Monitoring multifamily projects brings up privacy/permission issues and if we only got monitoring on central systems and not the dwelling units, that did not seem very useful to us for say, policy work.
The standard could still function as a building energy performance standard (BEPS) if the Authority adds monitoring requirements to Section 7 – those would then need to be addressed in the Ongoing Commissioning (OCx) Plan per section 8.10.2.11 (in the Hand-off Phase). The OCx Plan and reports are subject to review by the Authority if so required, per section 8.10.10 and 8.11.11.
We will make a database of weather files. As in our new construction program, custom weather data is required in case there are no nearby stations, or project elevation differs from that of the station location.
The review of Cx reports having to do with electives is mostly on the Owner rather than Phius. As before, the commissioning provider (CxP) is to document that all the requirements are being met – the owner-elected as well as the minimums of the standard.
Phius review of the Assessment Phase report is mainly concerned with the initial performance modeling. The review of the full investigation report on indoor air quality and site hazard issues happens later in the process.
The required monitoring period for nonresidential projects is zero for now.
The life cycle analysis period was put to the discretion of the Authority in the standard; Phius practice is 70 years.
Like all of our standards, Phius REVIVE 2024 will evolve. We are grateful for the input we’ve received thus far and look forward to collaborating with our community to make Phius REVIVE 2024 the standard solution for retrofits.
