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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

#21

Post by abakker »

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. This can happen in in humid climates with inadequate insulation - especially fiberglass where moisture can easily penetrate the fiberglass to reach the colder outside walls.

I agree, though. Air tightness and continuous insulation coupled with well-engineered ventilation is best.

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

#22

Post by throw0101a »

nraynaud wrote: post #11
duxup wrote: post #6

Earlier quoted context omitted.

I don't know much about LEEDs and maybe that should be updated, but I live in a cold climate and I see a lot of focus on insulation and insulation efficiency, both in new construction and updating old buildings. This idea that there's not a focus on insulation in the west seems kinda strange to me.

Same in France, I'm buying a condo and looking into all this for the renovation, and everybody is screaming "insulation by the outside".

If you want to make sure things are built properly, look into the topic of "building science":

* https://www.buildingscience.com/documents/insights/bsi-001-t...

Matt Risinger, a general contractor in Austin, Texas, has a lot of good videos on the topics:

* https://www.youtube.com/c/MattRisinger/videos

Even if you can't use the same techniques that he does (and pay for some of the premium products), it may be possible to still use some of the general theory / principles.

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

#23

Post by macinjosh »

I once lived in a LEED certified apartment complex. Unfortunately, I do not recall the specifics of their certification. My hot water would never get hot enough. I realized the hot water heater had a device on it to limit how often heating occurred. I promptly disabled it and had normal hot water again.

One of the other "green" aspects of the complex was that it only had compact car parking. However, the area I live in is rural/suburban and a very large portion of renters here work in the shale oil fields of the area. These workers drive trucks. Big trucks. The parking lot was always cramped mess. I often pondered the irony there and also how much more carbon was emitted by the body shops fixing all the dented doors.

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

#24

Post by baybal2 »

etimberg wrote: post #14
baybal2 wrote: post #2

The biggest issue I see is that LEEDs allow for a building that looks like a big heat exchanger, and has zero heat insulation to certify for high power efficiency in a cold climate. Canada, and Toronto area had tons of LEEDs certed luxury condos being heated like no tomorrow in Winter. Things are even worse in Vancouver, but that's offset by milder weather. The opposite picture is there in hot climates. Building with…

I live in an apartment in Toronto that is LEED certified. To be honest, it's not that great but for different reasons than you outlines. The insulation is too good and so the building is too warm all year round. My unit can easily be > 24C without any heating running even in winter.

Yep, but probably it has nothing to do with LEEDs, but just Canadian own construction experience that is not even code mandated.

LEEDs for example allows for buildings with completely catastrophical thermal design to get certified: https://upload.wikimedia.org/wikipedia/commons/8/8c/Aqua_Tow... (Chicago)

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

#25

Post by blacktriangle »

throw0101a wrote: post #17
blacktriangle wrote: post #15

Earlier quoted context omitted.

"There's this enthusiasm for environmentalism that seems to be blind to outcome." I am completely stealing this line, because it explains the modern environmental movement perfectly. I've argued with so many people about the Paris Accords and how they are a terrible idea. Why? Because they heap regulation on the West while sending money to China and India who have no obligation to improve their environmental policy.…

> Because they heap regulation on the West while sending money to China and India who have no obligation to improve their environmental policy. Both China and India are signatories of the Paris Accords. They are aiming to meet their targets. The US, at least for the four previous years, wasn't even in the Accords and not trying to do much in that time. There are no regulations in the Accords, just a goal with regards…

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.

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

#26

Post by [deleted] »

etimberg wrote: post #14
baybal2 wrote: post #2

The biggest issue I see is that LEEDs allow for a building that looks like a big heat exchanger, and has zero heat insulation to certify for high power efficiency in a cold climate. Canada, and Toronto area had tons of LEEDs certed luxury condos being heated like no tomorrow in Winter. Things are even worse in Vancouver, but that's offset by milder weather. The opposite picture is there in hot climates. Building with…

I live in an apartment in Toronto that is LEED certified. To be honest, it's not that great but for different reasons than you outlines. The insulation is too good and so the building is too warm all year round. My unit can easily be > 24C without any heating running even in winter.

[deleted]

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

#27

Post by fatnoah »

ensignavenger wrote: post #10

The article points out that LEED certification is about more than just energy efficiency, and a building can obtain LEED certification without being energy efficient by focusing on other LEED areas.

I worked in a LEED gold building. One summer weekend, I stopped by the office to pick something up and noticed that the AC was still fully operational and keeping the building cool, despite there being no one in the building.

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

#28

Post by Spooky23 »

duxup wrote: post #6
baybal2 wrote: post #2

The biggest issue I see is that LEEDs allow for a building that looks like a big heat exchanger, and has zero heat insulation to certify for high power efficiency in a cold climate. Canada, and Toronto area had tons of LEEDs certed luxury condos being heated like no tomorrow in Winter. Things are even worse in Vancouver, but that's offset by milder weather. The opposite picture is there in hot climates. Building with…

I don't know much about LEEDs and maybe that should be updated, but I live in a cold climate and I see a lot of focus on insulation and insulation efficiency, both in new construction and updating old buildings. This idea that there's not a focus on insulation in the west seems kinda strange to me.

The problem is engineers look at this like engineers and make assumptions and decisions based on the objectives given and their toolkit. When you hire an ASHRAE certified engineer, he’s going to be all about HVAC, based on whatever the architect produced.

Usually that means a focus on less energy usage. That frequently doesn’t align with lower cost or optimal solution. For example, buying a 95% efficient boiler for my home would cost significantly more over its useful life when you account for capital costs, retrofit for exhaust, and operational/maintenance expense (efficient units require annual inspection and maintenance via service contract). 80% results in more fuel consumption, but significant lower TCO.

In commercial or larger buildings, the obsession with sealing windows introduces lots of waste. The cost of more heating efficiency is more A/C days.

Also, the practices around construction have changed, driven partially by “efficiency” to build boxes with no passive ventilation. If you go into a well-designed circa 1910 building like a school, office and other inhabited spaces had higher ceilings, higher windows, etc that permitted passive ventilation. My house in upstate NY is like this... we use air conditioning for <20 days a year, and our extra heating costs are negligible. My neighbor’s circa 1995 house is a modern series of interconnected boxes — they have to run AC from June-September because there is no effective ventilation.

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

#29

Post by throw0101a »

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…

> Certain building materials need to breath.

As explained in the linked video, they actually need to dry. This does not need to happen to the outside environment. IMHO, using the two terms (dry/breathe) interchangeably is causing confusion, as each has certain connotations in many people's minds.

The person in that video lives in Austin, Texas, and when he builds or renovates structures he has a stand-alone, whole-house dehumidifier designed into the HVAC system (the client can of course reject the suggestion):

* https://www.youtube.com/watch?v=OKJnP_6uxcg

> If the there are discontinuities it is possible to get condensation when the temperature / dew point align just wrong.

Which, as explained in the first link (BSI-001), is why you want external insulation (if possible); some portion of the insulation being continuous is code in many places nowadays. That way the condensation occurs on the outside of the water/vapour control layer. Joe Lstiburek:

* https://www.youtube.com/watch?v=rkfAcWpOYAA&t=25m26s

This is harder to do with renovations, but is code in most places. In Ontario, Canada the code (IIRC) also specifics what minimum portion of the insulation that should be on the 'outside' of the vapour control layer: the colder the region the more has to be external, so that condensation happens on the outside of the structure.

Having it 100% external is ideal, but would cause trade-offs in other aspects of the building, which may not be desirable. An example of such a structure:

* During construction: https://www.youtube.com/watch?v=d8i-93ABo3I

* Finished: https://www.youtube.com/watch?v=hTwq-qUnr9I

Sadly, last time I checked, there was still no mandatory air tightness test for new builds in Ontario.

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

#30

Post by CalRobert »

throw0101a wrote: post #22
nraynaud wrote: post #11

Earlier quoted context omitted.

Same in France, I'm buying a condo and looking into all this for the renovation, and everybody is screaming "insulation by the outside".

If you want to make sure things are built properly, look into the topic of "building science": * https://www.buildingscience.com/documents/insights/bsi-001-t... Matt Risinger, a general contractor in Austin, Texas, has a lot of good videos on the topics: * https://www.youtube.com/c/MattRisinger/videos Even if you can't use the same techniques that he does (and pay for some of the premium products), it may be possible…

Risinger makes great videos. Doing a 150sqm extension now and plan to apply perfect wall concepts.
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