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Does LEED Certification Save Energy? Evidence from Federal Buildings

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Re: Does LEED Certification Save Energy? Evidence from Federal Buildings

#91

Post by MertsA »

ggm wrote: post #81
throw0101a wrote: post #16

The focus of buildings should be: 1. Keeping dry and bulk water out/away. 2. Being as air tight as possible.† 3. Controlling vapour. 4. Being well-insulated. * https://www.buildingscience.com/documents/insights/bsi-001-t... † Air is exchanged in a controlled fashioned: filtered for pollen and other things, and then tempered with an HRV/ERV. Buildings do not need to 'breathe': * https://www.youtube.com/watch?v=CIcrXut…

How long for VOC purge post build, pre occupancy?

What he's suggesting is an ERV or HRV. You still get air exchange, as much as you want, but now you're passing that air through a heat exchanger and a "humidity exchanger" so you're not wasting all of that energy to condition that air. Another big benefit, now you don't have that moist outside air passing through fiberglass insulation batts in the walls working like growth media for mold.

As far as VOCs, you can crank up the air exchange to something on par with what a leaky building would do naturally. Even if you didn't, VOC off gassing should be basically the same rate. It's not going to accumulate enough in the air to substantially change the amount slowly coming out of paint, carpet, drywall, etc. If the air exchange rate was e.g. half then that should almost double the VOCs in the air.

Re: Does LEED Certification Save Energy? Evidence from Federal Buildings

#92

Post by twothamendment »

I haven't built LEED, but how we build can for sure save energy. After building 3 homes in the USA, some basic updates to building codes would likely do more good than LEED will ever do.

It is so hard to convince people that the codes are the minimum. Who wants a product built to the minimum standard? Why doesn't the "market" demand it? Because people want cheap houses and the builder doesn't have to live in it or pay the utility bill. Buyers don't often ask for or compare bills on similar homes, so there is no point to upgrading insulation or HVAC unless you plan to stay in the home.

My oh-so-official-and-comprehensive-data: One home I built was very typical for the neighborhood, except insulation and a slightly better HVAC system, nothing exotic. When the power was out and everyone was complaining that their houses were 40 degrees, we were still at 60. Our bills were sometimes half what our neighbors were. What did it take? About $4,000 on a $250,000 build (in 2007). The new owners of the home didn't know what they were getting b/c nobody asks or cares. We keep in touch and they've found the same when comparing to the neighborhood. If you are wondering, no the house didn't sell for more because it saves energy and money - that isn't on a real estate comp.

If we would just tweak the building codes just a tiny bit and it would make a huge difference.

Re: Does LEED Certification Save Energy? Evidence from Federal Buildings

#93

Post by MertsA »

abakker wrote: post #21
throw0101a wrote: post #16

The focus of buildings should be: 1. Keeping dry and bulk water out/away. 2. Being as air tight as possible.† 3. Controlling vapour. 4. Being well-insulated. * https://www.buildingscience.com/documents/insights/bsi-001-t... † Air is exchanged in a controlled fashioned: filtered for pollen and other things, and then tempered with an HRV/ERV. Buildings do not need to 'breathe': * https://www.youtube.com/watch?v=CIcrXut…

Certain building materials need to breath. Buildings built with green wood which has more moisture than ambient, and buildings with cast concrete will shed water vapor for some time. If this can be managed, it is fine. Additionally, through all insulation there is an internal temperature gradient. If the there are discontinuities it is possible to get condensation when the temperature / dew point align just wrong. Th…

>Additionally, through all insulation there is an internal temperature gradient. If the there are discontinuities it is possible to get condensation when the temperature / dew point align just wrong.

Which is a good benefit of spray foam insulation. Your insulation is your air barrier and even if there was moisture in the pores of some open cell foam, it's not going to cause issues.

Re: Does LEED Certification Save Energy? Evidence from Federal Buildings

#94

Post by ggm »

MertsA wrote: post #91
ggm wrote: post #81

Earlier quoted context omitted.

How long for VOC purge post build, pre occupancy?

What he's suggesting is an ERV or HRV. You still get air exchange, as much as you want, but now you're passing that air through a heat exchanger and a "humidity exchanger" so you're not wasting all of that energy to condition that air. Another big benefit, now you don't have that moist outside air passing through fiberglass insulation batts in the walls working like growth media for mold. As far as VOCs, you can cran…

I would hope it's an exponential drop off, and you could even wedge doors open and drive ahead of things and then go back into a more passive house fully sealed state.

Re: Does LEED Certification Save Energy? Evidence from Federal Buildings

#95

Post by nenaan »

hristov wrote: post #79

It is comforting to see this discussion continues the great HN tradition of having a lively and wide-ranging debate about a complex scientific article or paper without ever bothering to read the article and paper. This is a rather complex paper, so I perused it for about five minutes. As such I consider my self a one eyed man among a hoard of shouting extremely opinionated blind people, so you should all listen to me…

TLDR?

Re: Does LEED Certification Save Energy? Evidence from Federal Buildings

#96

Post by jessaustin »

ceejayoz wrote: post #32
blacktriangle wrote: post #25

Earlier quoted context omitted.

Reducing them is great. Trusting China to self-regulate their emissions is the height of stupidity. Us paying China to then turn around and lie is even dumber yet. Want to reduce CO2? You'll need to embargo China and then start ramping up domestic regulation.

Reducing emissions by triggering World War Three is a plan, I suppose.

Any time "the leaders of the world" get together for any stated purpose, some of them are trying to bring about exactly this.

Re: Does LEED Certification Save Energy? Evidence from Federal Buildings

#97

Post by jessaustin »

wussboy wrote: post #18
arbitrage wrote: post #4

a building i used to work in got retrofitted to be leads certified. it got a new front door vestibule. the doors don't hang right, it's obstructive for people with different mobility needs. it leeks air like a tattered balloon. none of the glaring issues in the basement were fixed. it got a leed certification. nobody really cares, it's just all a sham. no real point to leeds certs other than polishing a turd.

“I found a flaw in a LEED certified building, I ignored any other possible beneficial knock on effects of that flaw or other enhancements. Therefore LEED has no beneficial effect, either here or anywhere else.”

The point of certifications is that they make particular promises. If those promises are obviously broken, why bother? This is like a priest asking, "so what if God doesn't actually exist?"

Re: Does LEED Certification Save Energy? Evidence from Federal Buildings

#98

Post by throw0101a »

blacktriangle wrote: post #52
throw0101a wrote: post #37

Earlier quoted context omitted.

I've always liked the term " not on my watch ". It probably derives from the maritime world, but is useful in my sysadmin career. In many (larger) organizations you cannot ensure everything is running smoothly all the time. But you can look after everything in your own (IT) wheel house. As a Canadian I cannot do much about China's (or India's) action, but I can do stuff about what happens in Toronto, Ontario, Canada,…

The thing about global pollution, it's global. The actors you are pushing to progress don't have to stick around, they can just pick up and move. If you clean up your house, you didn't really clean up the problem, you just moved it somewhere else, making the problem worse.

Think global, act local:

* https://noahpinion.substack.com/p/decarbonization-think-glob...

Re: Does LEED Certification Save Energy? Evidence from Federal Buildings

#99

Post by poseva »

MertsA wrote: post #93
abakker wrote: post #21

Earlier quoted context omitted.

Certain building materials need to breath. Buildings built with green wood which has more moisture than ambient, and buildings with cast concrete will shed water vapor for some time. If this can be managed, it is fine. Additionally, through all insulation there is an internal temperature gradient. If the there are discontinuities it is possible to get condensation when the temperature / dew point align just wrong. Th…

>Additionally, through all insulation there is an internal temperature gradient. If the there are discontinuities it is possible to get condensation when the temperature / dew point align just wrong. Which is a good benefit of spray foam insulation. Your insulation is your air barrier and even if there was moisture in the pores of some open cell foam, it's not going to cause issues.

Foam insulation has other problems, see for eg. thermal drift.

Re: Does LEED Certification Save Energy? Evidence from Federal Buildings

#100

Post by MertsA »

ggm wrote: post #94
MertsA wrote: post #91

Earlier quoted context omitted.

What he's suggesting is an ERV or HRV. You still get air exchange, as much as you want, but now you're passing that air through a heat exchanger and a "humidity exchanger" so you're not wasting all of that energy to condition that air. Another big benefit, now you don't have that moist outside air passing through fiberglass insulation batts in the walls working like growth media for mold. As far as VOCs, you can cran…

I would hope it's an exponential drop off, and you could even wedge doors open and drive ahead of things and then go back into a more passive house fully sealed state.

That's not going to get it to come out of the material faster, that'll just reduce the amount in the air. You're still stuck waiting for it to permeate out of paint, carpet, adhesives, etc. You could increase ventilation to get the VOCs in the air to an acceptable level faster, but you're not substantially increasing the rate at which it's coming out of the materials.
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