Building rating systems such as Green Star, LEED, and Passive House are here to stay, but many builders and home owners have grown frustrated at their cost and complexity.
Would it be possible to improve the performance, quality, and sustainability of more homes with a simpler, more streamlined, and cheaper building standard?
As Allison Bailes, accredited energy consultant and writer, asked in his blog, ‚ÄúWouldn't it be great if we could list just a handful of measures that a home builder has to achieve to build a Pretty Good House?‚ÄĚ
It turns out that quite a few building professionals have been working on that very question. The ‚ÄúPretty Good House‚ÄĚ concept has evolved from some discussions among building professionals in Maine, such as Dan Kolbert, with a few blog posts by Michael Maines at Green Building Advisor helping to flesh out the ideas. Steve Konstantino owns Maine Green Building Supply, where the monthly discussions take place, and wrote a short but useful summary of the ideas.
‚ÄúI think the idea of the Pretty Good House, or PGH is to have a general list to use as a guide while making the design and build choices that every project has to make. It is a higher bar to set for the everyday builder that does not require certification,‚ÄĚ he wrote.
A Pretty Good House is a better house than the code-minimum house. Builders and home owners are given guidelines for all the home‚Äôs systems, such as foundation, insulation, HVAC and so on, with the flexibility to adopt any or all of the guidelines. It‚Äôs regionally optimized, too, so homes in different climate zones will differ.
Importantly, there‚Äôs no certification, so there‚Äôs no extra cost for compliance with the standard, and no Pretty Good House organization that requires funding.
Konstantino‚Äôs guidelines are organized as General, Site Considerations, Design, Foundations, Building Envelope, Windows, Mechanicals, and Interior Finishes. They represent a thoughtful list of best practices without being completely prescriptive.
According to Konstantino, some aspects of a Pretty Good House are general guidelines, such as:
‚óŹ ‚ÄúUse locally sourced materials and labor.
‚óŹ Keep the structure less complex.
‚óŹ Make things durable.‚ÄĚ
And some ideas are more specific. For the building envelope:
‚óŹ Build walls to R-40 with thermal break for cold climates.
‚óŹ Build ceilings to R-60 with thermal break for cold climates.
‚óŹ Aim for airtightness at 1.5 ACH 50 or better.
Some guidelines address sustainability:
‚óŹ ‚ÄúUse materials that have low embodied energy.
‚óŹ Keep the conditioned living space relatively small per occupant (maybe 600 s.f. for the first and 300-400 s.f. per additional occupant).
‚óŹ Avoid using fossil fuels.‚ÄĚ
Architects Chris Briley and Phil Kaplan also addressed the Pretty Good House concept in a recent Green Architect‚Äôs Lounge podcast, and emphasized that it‚Äôs about guidelines, not requirements.
‚ÄúInstead of saying, 'A pretty good house does these things: Check! Check! Check!', it‚Äôs really, 'A pretty good house considers these things,'‚ÄĚ Briley said. ‚ÄúThermal bridging would be a great example, like, 'A pretty good house takes thermal bridging into consideration and does something about it.'‚ÄĚ
Briley and Kaplan also emphasized the need to involve all the trade partners early in the process to optimize the design.
‚ÄúYou can‚Äôt just plop things in at the last minute and expect it to go smoothly, because someone‚Äôs going to have to move a beam to make room for something else,‚ÄĚ Briley said.
He noted, however, that energy modelling is strongly recommended.
Bailes floated a few of his own ideas in a blog post, as well. His approach outlines several specific benchmarks that would be appropriate for a house that‚Äôs better than code, but not up to Passive House or Green Star levels.
His is the most detailed approach so far, but as he points out, ‚ÄúI'm a fan of performance goals because they allow the project team to figure out how best to meet the goals, but some of the items are best left as prescriptive (e.g., no atmospheric combustion inside).‚ÄĚ
Bailes‚Äô elements include:
‚óŹ Pretty Good Design
‚óŹ Pretty Good Building Envelope and Weather Shell
‚óŹ Pretty Good Mechanical Systems
‚óŹ Pretty Good Water Conservation
‚óŹ Pretty Good Verification
‚óŹ Pretty Good Homeowner Package
‚óŹ Pretty Good Performance.
Many builders and home owners grasp the Pretty Good House idea immediately, even if they differ about the details.
‚ÄúPeople have different versions of what "pretty good" is,‚ÄĚ Konstantino said. ‚ÄúI do think some of the basic building science principles should always be adhered to, including some way to verify that it is done properly (i.e.: a blower door test).‚ÄĚ