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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

#41

Post by leetcrew »

Spooky23 wrote: post #28
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.

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 m…

I know you only said "partially by efficiency", but the other part is pretty important. another goal of sealing the building is to align the moisture and thermal barriers with each other. this is important, because this is how you control humidity inside the envelope. in theory, this makes it much less likely that you get mold, rot, etc. if you're going to heat/cool your house at all, you really don't want heated inside air getting cooled down in the winter or warm outside air getting cooled in the summer. if you have significant passive ventilation, you don't really have a moisture or thermal barrier.

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

#42

Post by lupire »

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…

Problem is once someone built a cheap building 30 years ago, it's not worth $200K to tear it down and rebuild for thermal efficiency.

And new build buyers want homes that look "normal" or "classic", not experimental (even if experimental is based on proved designs elsewhere.)

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

#43

Post by dashundchen »

macinjosh wrote: post #23

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…

That may not have been for LEED, many areas in the US have anti-scalding regulations for buildings or landlords/operators - typically not to exceed 120F at the tap. May have been set low depending on how many taps, distance between the different taps etc.

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

#44

Post by throw0101a »

chrisabrams wrote: post #34
etimberg wrote: post #14

Earlier quoted context omitted.

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.

Is it possible that all of your neighbors in your building have their heater on? This is what happened to me in a building in NYC. It would actually get so warm in the winter I would have to crack the window open or I would get a nose bleed.

As someone who also lives in Toronto: most things being built now are giant class towers.

Now, glass sucks at insulation (even triple glaze), but—depending on the coatings—it lets in a lot of sun light and with that potentially heat.

While in a perfect world there would be no / minimal exchange between the inside of the structure and the outside,† being too warm may be better than being too cold, as I'm guessing that it's easier to throw away the 'free' heat of the sun away than introducing it in winter. Certainly heat pumps can go either way, but I figure that it's easier to dump it.

† The entire point of "buildings" are to be environmental separators after all.

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

#45

Post by TeMPOraL »

baybal2 wrote: post #40
reedjosh wrote: post #36

Earlier quoted context omitted.

This and most modern buildings are heated and cooled via a central heating/cooling system which distributes the hot/cold via water. So, it may be even though you don't have the heat 'on' there is still hot water running through your apartment's heating system.

Yep, and this is why central control, along with temperature sensors make a giant lot of sense to prevent such situation. A simple thermostat is not enough, and even a PID one will not do the job if external thermal influx is not in the model. I once worked on a HVAC controller for hotels in Singapore, and other commercial venues which helped the hotel operator to save on HVAC by packing visitors more closely dependi…

Doesn't all this imply there should be more focus on inter-floor and inter-room insulation, to effectively isolate floors/apartments/suites thermally from each other?

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

#46

Post by Scoundreller »

reedjosh wrote: post #36
julianlam wrote: post #33

Earlier quoted context omitted.

Are you sure it's because of the insulation? Many condos are sweltering in the middle spring (even with heat off) because residents living on floors below yours crank the heat and it all rises. When I lived in a condo (Bloor/Yonge), the situation was so bad (12th floor) that if it hit 12°C outside, I needed to turn on the A/C, which is awful from an environmental POV.

This and most modern buildings are heated and cooled via a central heating/cooling system which distributes the hot/cold via water. So, it may be even though you don't have the heat 'on' there is still hot water running through your apartment's heating system.

Quite possible parent was heating the loop water with their a/c which the North-facing residents extracted running their system in heat mode.

Which makes it all an incredibly inefficient system to move heat from the sun-facing side to the north side because you’re not allowed to prop open the damn doors.

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

#47

Post by peytn »

mistrial9 wrote: post #38

I did a small project for one of the founders of the LEED standard. I am in favor of the project and lacking details right this minute so I won't argue its merits BUT I can say that ... building specs are super useful, at the right time. Changes to a building can be very difficult, time-consuming and expensive, amidst a business model in West that emphasizes short-term money flow constantly. It is hugely difficult to…

Normal people worry about having a good job and saving for retirement. People in that world worry about things like UN Sustainable Development Goals. It’s a weird status thing they do, and I’m not sure we’re better off for it. I guess it beats the castle-building days of yore.

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

#48

Post by baybal2 »

lupire wrote: post #42
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…

Problem is once someone built a cheap building 30 years ago, it's not worth $200K to tear it down and rebuild for thermal efficiency. And new build buyers want homes that look "normal" or "classic", not experimental (even if experimental is based on proved designs elsewhere.)

From my experience on short stints in Dubai, and Qatar, single house residentials can well be both. Lots of villas there built with foam concrete exterior walls, in which you are living like in a thermos, and which still look rather conventional.

Their highrises are probably a bit more avant-garde than American ones, but nevertheless they sell like cookies.

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

#49

Post by throw0101a »

abakker wrote: post #39
throw0101a wrote: post #29

Earlier quoted context omitted.

> 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-h…

Here in Boulder County, new BuildSmart regulations will require new and renovated structures to pass a "Blower Door Test" Does Ontario not have any of those requirements for commercial or residential? Agree on the continuous insulation. Very hard to do for Renovations. Fortunately in Colorado, it is so dry that the vapor barrier is slightly less important than in places like new england.

> Does Ontario not have any of those requirements for commercial or residential?

Last time I checked it no air leakage testing is mandated:

* https://www.barriersciences.com/blog/potential-changes-ontar...

* https://www.reminetwork.com/articles/canada-wavers-on-airtig...

I'm not in the industry, so only know about the rough outlines through casual interest.

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

#50

Post by macinjosh »

dashundchen wrote: post #43
macinjosh wrote: post #23

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…

That may not have been for LEED, many areas in the US have anti-scalding regulations for buildings or landlords/operators - typically not to exceed 120F at the tap. May have been set low depending on how many taps, distance between the different taps etc.

Interesting. The water never got warmer than about 100-105 with the device on. Perhaps it was defective.
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