I wish you did a bit of history on the code process in California - which has its own energy code. Back in the 80's and 90's during the back to the land movement there was a lot of push back on the UBC by a group called United We Stand that called for simpler codes and more owner builder codes. This group discovered that industry was buying the expensive memberships to the code council. Getting that out in to the open led eventually to the democratizing of the process. Now we are going backwards. As a builder/Architect I have more objections to the insertions of ridiculus electrical requirements such as too many outlets which lead to bigger main panels. In the kitchen for instance the requirement for tons of outlets allowed appliance makers to reduce the length of cords -making lots of money a penny at a time. The newer energy codes help us all, but I do think a person should be able to build their own home without the need of professionals. That would save 10% on the cost of home building right off the bat. Interesting topic so Thanks!

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Anyone have a source for the federal home loan backing being tied to new building codes?

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I'd love to see an analysis of increasing energy efficiency vs. increasing cost of construction of residential units. When do we reach diminishing returns? I ask as a local gov't practitioner who is concerned about both climate and housing affordability. Here in Mass. with the latest codes coming into force we are seeing some troubling trends with dramatically increasing cost of construction driven partially by the hours of extra labor and materials needed to meet energy code. Additionally local building officials are doing things that are absolutely unreasonable. Such as upon any minor change in footprint or a renovation that would add a certain amount of value, requiring full energy code upgrade to an existing home. In some cases this completely shuts down construction because many old 19th and early 20th century homes simply cannot meet these modern codes in any scenario. In a state with such an old building stock this is a recipe for allowing our existing housing to decay. What's the sweet spot here? Are we allowing the perfect to be the enemy of the good with codes?

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Mar 25·edited Mar 25

My former residence, Marina Towers, hundreds of Chicago apartments in 2 - 60 story towers, was all electric when built in 1964 and remains so today.

It was well known 60 years ago that "Natural gas" was not much more healthful over the long term than the manufactured "coke gas" it had replaced, and with many of the same "naturally found in the ground" toxins.

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Things get pretty complicated with the latest code improvements. This podcast was great, but because you mostly focused on electrification in the code missed some things I would like to hear more about.

I live in MA, which is Climate Zone 5. I like to listen to building podcasts and websites as well as energy. My understanding from them (Fine Home Building and Green Building Advisor) is that once we go past the prescriptive R20 in a wall you have two choices: drastically change how you build or use closed cell spray foam.

Prescriptive code was (is? I'm still not totally sure on the timing here and if it was rolled back) either:

* a wood framed wall with R20 insulation between the studs. (This needs to be framed with 2x6 studs to get the depth required.)

* a wood framed wall with R13 in the cavity and R5 on the outside of the house. (This can use 2x4 studs still but needs insulation boards.)

To meet the R20 cavity insulation builders moved to 2x6 studs for framing. Very few changes were otherwise needed to do this. Air sealing had to improve too, yes, and that's one of the multiple reasons you now see green Huber Zip everywhere. This increased cost, but you made up for it in energy savings.

To use the R5 continuous insulation method on the outside requires very different practices to make windows water tight, fasten them, detail around doors, etc. etc. In addition, the foam board used is *expensive* AND until recently used blowing agents to make the foam that were 1,000sx worse than CO2 for global warming per ton. If you do value engineering I've heard contractors say that the expense of R5 foam board and the detailing never paid for itself. Other efficient energy building did, but not that one.

Then we want to get even more energy savings in the code and go to R30.

There is only one* way to get to R30 using cavity insulation and not changing other details and practices: Closed Cell Spray Foam. This stuff is expensive, requires a bunny suit and respirator to install, sometimes never finishes off gassing, and... Then we get to the blowing agents! There are low global warming potential blowing agents but they are new on the market. Even when you get the ones blown with the low GWP foaming agents you're still basically insulating your house using 5.5 inches of plastic foam with all the emissions that implies.

Ideally builders would learn new practices. Build with double stud walls, larsen trusses, some other available methods. However, if your business is speculative building on a new house learning means losing money. So either the building gets more expensive while they learn, or they get compensated some other way.

Anyway, GBA has a ton of articles on embodied carbon in housing construction, practices to avoid it. There's even a practice discussed a lot, "Pretty Good House," intended to make energy efficient houses that don't cost a ton and don't require more emissions to build than they will ever save in operating emissions.

I would love a Volts episode diving deeper into this problem. I recommend the folks over at Taunton Press as people to talk to.




* Ok, technically you could use aerogel to get here, but that's not an economical or practical solution at the moment. Outside of historical buildings and a couple, "oops we forgot insulation in the high rise plans," it's just not used.

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Thanks for touching this, it feels like the briefest scrape of the surface. Get an architect on, I vote for Michael Eliason (Seattle local) as he can talk about how different standards and ways of building can lead to different outcomes with examples from Germany/Europe.

Another commenter (Bruce B) called out the outlet requirements and implications on the panel (and profit margin of appliance makers) and that's just another layer in the electrical code onion. The *number* of outlets in the kitchen doesn't change the actual load of appliances in the kitchen - it shouldn't change the panel! But it does because our codes are built to stop the worst behaviors not usually to encourage the best or latest technologies. If you had an outlet sharing plug between the kitchen outlet and the panel you'd have the same security against overdraw, if you had a dynamic panel or local load balancing within the house itself (Kitchen battery, Laundry room battery, HVAC and HW Heater battery) you could do similar. But you can't, not really, because the local codes would either force redundancy or extreme expertise making a better outcome massively more expensive.

Yes, a story of regulatory capture by the industry meant to be regulated. But there are alternatives and we should get to those systematically instead of waiting on private startups to address them one facet at a time (smart panels, battery supported induction stoves - all are sub-optimal solutions to the home electrification problem if you were free to design for the whole system instead of fit into legacy constraints). Retrofit is a big gnarly problem, but most of these codes apply to new construction!

And that's part 2, what to build doesn't change where building is allowed. That deserves its own drill down, mandating things like 1:1 housing to job growth would be transformative today, and still not enough in the long run. Everyone loves growth, tie that to the other side of a place for that growth to go.

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Two more comments since I'm so excited by codes getting some notice:

Great to hear the shout out for Duane Jonlin - he took on the thankless task of chairing the changes through long contentious meetings.

One minor point is that codes were contentious long before 2019. Industry groups sued often, occasionally winning. The 2009 and especially 2012 versions were big wins for efficiency as well. Then the sad set of cycles with no marked improvement occurred. See graphic after some scrolling. https://www.swinter.com/party-walls/2024-iecc-residential-code-requirements/

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Energy codes are, and I expect will continue to be, the primary driver of efficiency on the demand side. I serve on the Washington State Building Code Council and help lead the development of our energy codes. Codes are primarily a bulwark against the short term cost and profit constraints of those who build buildings. It would be easier and cheaper to not build a fire rated wall between two spaces, but sometimes later when there is a fire, the rated wall's importance is clear. With energy codes, they do increase first cost (except in some cases like electrification where the gas line is simply not extended and built into the home) but those interested in housing affordability may consider the longer term view that being able to afford a home includes utility bills. Water and energy cost savings are key, and continue each month, each year, and are just as real as mortgage payments. Energy codes are not the primary driver of increased housing costs. Land use, permitting processes, environmental review, inflation, interest rates, and others have more of an impact on increased housing costs. In fact, energy codes are one of the few things that actually have payback in terms of comfort, resilience, and energy cost.

Further, energy use reductions in code mean we haven't needed to build more new power plants, keeping prices lower. The Power Plans for Washington/region have typically maintained over the last decades that efficiency is the cheapest form of new energy. With EVs and electrification, we do need to build new renewable energy. But as covered in the Land Use pod and others, we need to build a lot less new renewable energy if we first get amazing efficiency out of our buildings. WA energy codes have a legislatively mandated target of 70% below 2006 energy code levels by 2031 and we roughly are on track to do that. This means 70% less new renewable energy, land use, permitting, transmission, embodied carbon of new renewable energy, permitting headaches, etc. WA, like several states, have better energy codes than the IECC. In fact, we (WA) export more code ideas to the next version of the IECC than we get advances through the IECC when it comes out. We even have a demand response requirement in the latest version of the energy codes.

Thanks for doing this pod. Hopefully the environmental public will begin to understand and support code workings just like we are beginning to understand FERC and industrial decarbonization/hot rocks.

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I cannot believe that WA can use 70% less home energy by better insulation and using LEDs, (If LEDs were not prevalent in 2006). We should not "build a lot less" renewable energy. Instead we should build as much new renewable energy as we possibly can.

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Hi Steve, using insulation, LEDs, heat pumps for space and water heating, heat recovery, etc. can get us to (or beyond) 70%. The code is getting closer to Passivehouse, which includes thousands of built examples of this kind of efficiency.

I mean that we still need 100% (or 90-something%) renewable energy. But with efficiency, the total quantity of this renewable energy is less than without this efficiency. This means less land use, lower cost, less transmission, etc. And it means we can build it sooner since less needs to be built. Sorry if this wasn't clear.

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Great topic. I've been dealing with these energy codes for years on the commercial side. It's quite a quagmire, and in a few aspects I do think they have made things complicated w/o reducing GHG pollution. Of course for years their focus was just reducing operating cost, so when gas was cheap it made more sense to do things to reduce electricity use.

Clearly, putting in electric service for anything and then installing/using gas is an extra expense w/o even savings in utility bills. We know and have known how to build efficient electrified homes for a while, so that just seems silly, but I get why.

Instead of dumping dye on the Constitution, I wish the climate activist protesters would protest every gas-burning new building and subdivision. And somehow figure out how to dye CO2 black so folks could see how "clean" their gas is.

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