In this episode, I geek out with David Goldstein, founder of Hydronic Shell Technologies, about a novel building retrofit technology that wraps old multifamily structures in insulated panels with built-in HVAC systems. Goldstein's approach allows for energy-efficient upgrades without interior disruption, potentially solving a major challenge in building decarbonization.
As a NYC based company I am sure you're deeply in the know about Fire Codes and zoning rules. 2 questions: do the materials used by your company for exterior cladding, meet Fire Code requirements for multi-family buildings. Wouldn't want to rely on behind the wall water pipes to ensure fire suppression. As to Zoning, NYC has very strict rules about where a building footprint ends and the public sidewalk begins. How does your product with the 6" interior cavity + new exterior wall meet current zoning limitations?
This proposal has a couple conceptual flaws. Not working with setbacks and property lines as Nancy Anderson noted, seems kinda like a big dealbreaker, though those are issues with conventional Passivhaus retrofits as well. That’s why I was working with Representative Davina Duerr, Sightline and others on HB 2071 in the WA Legislature last session, which would have allowed intrusion into setbacks for Passivhaus buildings. That part of the bill got dropped by the Senate but we will try again in 2025.
What is the composition of the material that Goldstein using for the facade on his retrofits? The exterior fires at 8 Boulevard Walk in Dubai, at the Grenfell in London and at the Monte Carlo fire in Las Vegas were all attributable to various types of foam being used for insulation or for architectural statements. In all three of these fires you could see the liquified burning foam dripping off the buildings. You can’t wrap buildings in flammable materials.
As with some of the other comments, I think fire safety has to be a very important consideration
Grenfell is a very scary example when safety was not considered properly. The 6 inch gap between the cladding and the original exterior wall could act as a chimney.
Great discussion about this important topic. Local municipalities are afraid to even talk about this as there aren't simple fixes even though this is a key emissions area.
I have a different technical question from those above for David Goldstein from Hydronic Shell.
My question is about heating and cooling simultaneously in different parts of the building. I can easily come up with many scenarios where some portions of the building (or even individual residential units) may have a heating need while others may have a cooling need. It could be morning or afternoon sun and different sides of the building. It could be a large dinner gathering that used the oven a lot and a good bit of body heat to need AC in winter.
The podcast only briefly discussed providing hot or cold HVAC water to apartments. The video on the Hydronic Shell web site seems to indicate only a single pair of water tubes going to each HVAC unit and along the facade cavity. A single supply and return pair would indicate everyone gets heat or AC depending on the system setting.
Another question about providing HVAC services to individual residential units, are these costs to be included in the overall building operation? Or is each unit billed for the quantity of HVAC services they need? How is this measuring performed and subsequently billed?
And finally, an unrelated question. Are these facade manufacturers able to create panels around balconies with (usually) sliding glass windows? Depending on the floor plan layout and windows, could a HVAC unit be incorporated into a sliding glass door opening?
Along with the setbacks, and fire issues created by enclosing an existing building in a chimney, if he hasn’t already done so I’d suggest David Goldstein enlist the help of an expert in building science. Modeling the assembly in THERM would be enlightening I’m sure. Vlad Pezel of eMod Studio is brilliant and nearby.
Mr. Roberts -- One thing that isn't figured into this - is were is all of the electricity going to come from for all of the "built-in" HVAC?
If your interested in that -- you have the information that was was sent to you. It's called the "POD MOD" which continuously develops clean electricity "where needed" / "as needed".
And it can be installed "in" every apartment or office-space in every building this system is supposed to heal.
Nothing against this "fix" --= but without the available electric power -- this "fix" is good example of "...putting the cart before the horse..."
One of the bigger issues for retrofitting multifamily homes is that the owners rarely have a strong financial incentive to make the homes more energy efficient.
The reason why people do these projects is because they will save a large amount of money on their heating and electricity costs, so the cost of retrofitting the home is worth it. But the tenants are often the ones responsible for the AC (if they have window units), and many can be responsible for the heating costs.
Therefore upgrades that almost immediately pay for themselves in energy savings are often not done, as the landlord isn't going to see those energy savings. And when renters are looking for an apartment they rarely have a way to accurately estimate the heating/electricity costs. So a tenant is often more attracted to a unit that has a $1,500 rent with $200 in heat/electricity than an identical unit that upgraded equipment and rents at $1,575 with $100 in heat/electricity, as they have no way of knowing what the heat/electricity for a unit will be. So landlords can't easily capture the energy savings in higher rents to offset the costs of doing the upgrades.
A few states and cities have implemented a solution to this, by forcing landlords to disclose the average electricity/heat costs for a unit (Alaska, Hawaii, Kansas, Maine, Colorado and South Dakota), but more states need to adopt this or there needs to be a national law requiring this disclosure. It would also be beneficial to require this disclosure when selling a home, so people have an incentive to make upgrades even if they aren't going to make their money back before they sell the home.
What is the source of Goldstein's claim that buildings are the source of 40% of greenhouse gas emissions? According to the EPA (https://www.epa.gov/ghgemissions/global-greenhouse-gas-overview), buildings contribute only 8% of total global emissions, up to 16% if you include electricity.
From their report:
> Buildings (6% of 2019 global greenhouse gas emissions): Greenhouse gas emissions from this sector arise from onsite energy generation and burning fuels for heat in buildings or cooking in homes. Note: Emissions from this sector are 16% when electricity use in buildings is included in this sector instead of the Energy sector.
If you include all electricity and heat production, according to the EPA report, we arrive north of the 40%, so I'd really like to see a more specific citation for that number and what is being included in it.
If you multiply the total global greenhouse gas emissions due to energy production (~72%) by the 25% sector distribution for heating/cooling of residential and commercial buildings, you get 18% total contribution to global GHG production. Even if you assume that the EPA estimation of buildings' contribution to GHG emissions has NO inclusion of the cost of energy consumption for heating/cooling, the combined total still only goes up to about 26%. FAR LESS than the 40% cited by David Goldstein.
I'm all for better solutions to difficult problems in greening up existing infrastructure, but I don't like big scary numbers that aren't backed up by data, especially if they're being used to sell a product... Better insulation and more efficient heating/cooling are definitely very important, but let's not distract from that fossil fuel vehicles and industrial production processes are still the two largest factors in GHG emissions, and we simply cannot fix global warming without addressing those sectors.
As a NYC based company I am sure you're deeply in the know about Fire Codes and zoning rules. 2 questions: do the materials used by your company for exterior cladding, meet Fire Code requirements for multi-family buildings. Wouldn't want to rely on behind the wall water pipes to ensure fire suppression. As to Zoning, NYC has very strict rules about where a building footprint ends and the public sidewalk begins. How does your product with the 6" interior cavity + new exterior wall meet current zoning limitations?
This proposal has a couple conceptual flaws. Not working with setbacks and property lines as Nancy Anderson noted, seems kinda like a big dealbreaker, though those are issues with conventional Passivhaus retrofits as well. That’s why I was working with Representative Davina Duerr, Sightline and others on HB 2071 in the WA Legislature last session, which would have allowed intrusion into setbacks for Passivhaus buildings. That part of the bill got dropped by the Senate but we will try again in 2025.
What is the composition of the material that Goldstein using for the facade on his retrofits? The exterior fires at 8 Boulevard Walk in Dubai, at the Grenfell in London and at the Monte Carlo fire in Las Vegas were all attributable to various types of foam being used for insulation or for architectural statements. In all three of these fires you could see the liquified burning foam dripping off the buildings. You can’t wrap buildings in flammable materials.
POAH is doing something similar in Salem, MA and the DOER energy office has a $40m grant program: https://www.mass.gov/info-details/affordable-housing-decarbonization-grant-program
As with some of the other comments, I think fire safety has to be a very important consideration
Grenfell is a very scary example when safety was not considered properly. The 6 inch gap between the cladding and the original exterior wall could act as a chimney.
Great discussion about this important topic. Local municipalities are afraid to even talk about this as there aren't simple fixes even though this is a key emissions area.
I have a different technical question from those above for David Goldstein from Hydronic Shell.
My question is about heating and cooling simultaneously in different parts of the building. I can easily come up with many scenarios where some portions of the building (or even individual residential units) may have a heating need while others may have a cooling need. It could be morning or afternoon sun and different sides of the building. It could be a large dinner gathering that used the oven a lot and a good bit of body heat to need AC in winter.
The podcast only briefly discussed providing hot or cold HVAC water to apartments. The video on the Hydronic Shell web site seems to indicate only a single pair of water tubes going to each HVAC unit and along the facade cavity. A single supply and return pair would indicate everyone gets heat or AC depending on the system setting.
Another question about providing HVAC services to individual residential units, are these costs to be included in the overall building operation? Or is each unit billed for the quantity of HVAC services they need? How is this measuring performed and subsequently billed?
And finally, an unrelated question. Are these facade manufacturers able to create panels around balconies with (usually) sliding glass windows? Depending on the floor plan layout and windows, could a HVAC unit be incorporated into a sliding glass door opening?
One simple response to the questions on fire safety: non-combustible materials.
Along with the setbacks, and fire issues created by enclosing an existing building in a chimney, if he hasn’t already done so I’d suggest David Goldstein enlist the help of an expert in building science. Modeling the assembly in THERM would be enlightening I’m sure. Vlad Pezel of eMod Studio is brilliant and nearby.
Living in much smaller city, I’m wondering about this as a primary building material.
Mr. Roberts -- One thing that isn't figured into this - is were is all of the electricity going to come from for all of the "built-in" HVAC?
If your interested in that -- you have the information that was was sent to you. It's called the "POD MOD" which continuously develops clean electricity "where needed" / "as needed".
And it can be installed "in" every apartment or office-space in every building this system is supposed to heal.
Nothing against this "fix" --= but without the available electric power -- this "fix" is good example of "...putting the cart before the horse..."
One of the bigger issues for retrofitting multifamily homes is that the owners rarely have a strong financial incentive to make the homes more energy efficient.
The reason why people do these projects is because they will save a large amount of money on their heating and electricity costs, so the cost of retrofitting the home is worth it. But the tenants are often the ones responsible for the AC (if they have window units), and many can be responsible for the heating costs.
Therefore upgrades that almost immediately pay for themselves in energy savings are often not done, as the landlord isn't going to see those energy savings. And when renters are looking for an apartment they rarely have a way to accurately estimate the heating/electricity costs. So a tenant is often more attracted to a unit that has a $1,500 rent with $200 in heat/electricity than an identical unit that upgraded equipment and rents at $1,575 with $100 in heat/electricity, as they have no way of knowing what the heat/electricity for a unit will be. So landlords can't easily capture the energy savings in higher rents to offset the costs of doing the upgrades.
A few states and cities have implemented a solution to this, by forcing landlords to disclose the average electricity/heat costs for a unit (Alaska, Hawaii, Kansas, Maine, Colorado and South Dakota), but more states need to adopt this or there needs to be a national law requiring this disclosure. It would also be beneficial to require this disclosure when selling a home, so people have an incentive to make upgrades even if they aren't going to make their money back before they sell the home.
What is the source of Goldstein's claim that buildings are the source of 40% of greenhouse gas emissions? According to the EPA (https://www.epa.gov/ghgemissions/global-greenhouse-gas-overview), buildings contribute only 8% of total global emissions, up to 16% if you include electricity.
From their report:
> Buildings (6% of 2019 global greenhouse gas emissions): Greenhouse gas emissions from this sector arise from onsite energy generation and burning fuels for heat in buildings or cooking in homes. Note: Emissions from this sector are 16% when electricity use in buildings is included in this sector instead of the Energy sector.
If you include all electricity and heat production, according to the EPA report, we arrive north of the 40%, so I'd really like to see a more specific citation for that number and what is being included in it.
According to an MIT review (https://climate.mit.edu/explainers/heating-and-cooling), "almost 25% of the energy produced worldwide is used to heat and cool homes and commercial buildings."
If you multiply the total global greenhouse gas emissions due to energy production (~72%) by the 25% sector distribution for heating/cooling of residential and commercial buildings, you get 18% total contribution to global GHG production. Even if you assume that the EPA estimation of buildings' contribution to GHG emissions has NO inclusion of the cost of energy consumption for heating/cooling, the combined total still only goes up to about 26%. FAR LESS than the 40% cited by David Goldstein.
I'm all for better solutions to difficult problems in greening up existing infrastructure, but I don't like big scary numbers that aren't backed up by data, especially if they're being used to sell a product... Better insulation and more efficient heating/cooling are definitely very important, but let's not distract from that fossil fuel vehicles and industrial production processes are still the two largest factors in GHG emissions, and we simply cannot fix global warming without addressing those sectors.