3 ms·

For an A+++ energy rated house, you can't have holes in walls where I live. That means you can't have cooker extractors that extract, you can only have them run

by brnt 4y ago

For an A+++ energy rated house, you can't have holes in walls where I live. That means you can't have cooker extractors that extract, you can only have them run the air through a filter. But this is really silly, because a major 'exhaust' is water vapor, which filters don't help with. A more humid house is bad for many reasons, and often results in people opening windows anyway. Yes, an A+++ house also requires air refreshing with energy recovery, but it takes ages to get that sort of humidity out that way. Running an airco just for dehumidification is also expensive. It's short sighted imho. The extractor is precisely the right place to just move air out for all kinds of health reasons, maybe someone should work on one that recaptures some of the heat (that would also make sense!); I have not yet seen one.

fnomnom 4y ago
there are a lot of available ventilation solutions that recover the energy and cycle air in your use. they start at 200€ a unit and go up from there. i think the modern cooking extractors are all built into the countertops and just filter the air. at least thats the trend in germany
- brnt 4y ago
  The point is that those systems do not integrate with extractors, and filtering only removed VOCs and particulates, not water vapour, which you would prefer to extract as well. Heat recovery from an extractor (eg remove heat from air before expelling) would achieve the goal the rating is aimed at, without compromising indoor air quality by not having a way to remove humidity. Or maybe another kind of integrated dehumidifier that discharges in your sink/plumbing maybe. Those filter-only extractors won't do for anyone serious about indoor air quality.
  - fnomnom 4y ago
    yeah but in my opinion in modern homes this is automated and regulated house-wide with the mentioned air circulators that recover the energy. they also expell humidity afaik
    - brnt 4y ago
      You'll still have to accept an hour or so of elevated humidity. I prefer not to.
nice__two 4y ago
Berbel has a unit that opens when using the unit and closes, when not in use. Quite ingenious, if you ask me. [1]: https://www.berbel.de/dunstabzuege/zubehoer/abluft-zubehoer/mauerkasten/ https://www.berbel.de/dunstabzuege/zubehoer/abluft-zubehoer/...
- brnt 4y ago
  That's clever, but this [1] is already common and I guess not much worse? [1] https://www.ventilatieshop.com/terugslagklep-in-ventilatiekanaal-150mm/ https://www.ventilatieshop.com/terugslagklep-in-ventilatieka...
  - nice__two 4y ago
    It is much worse. The Berbel retains the insulation provided by the wall, when closed. This is nothing more than a fancy hole in the wall. Opening and closing, means you get the best of both worlds.
throw0101a 4y ago
> For an A+++ energy rated house, you can't have holes in walls where I live. That means you can't have cooker extractors that extract, you can only have them run the air through a filter. It's possible to install dampers that are normally closed for airtightness, but open when the kitchen vent is activated (both on the exhaust, and makeup air, side of things): * https://www.greenbuildingadvisor.com/article/makeup-air-for-kitchen-exhaust https://www.greenbuildingadvisor.com/article/makeup-air-for-... Even the Passive House folks are fine with this arrangement (§3.4): > When the exhaust air system is not operating the exhaust air and intake air vents should close airtight and should not cause any leakage volume flow. Furthermore, additional insulation will be advantageous at these locations. * https://passiv.de/downloads/05_extractor_hoods_guideline.pdf https://passiv.de/downloads/05_extractor_hoods_guideline.pdf So I'm not sure why your building codes mandate recirculation, since I'm guessing even they wouldn't be as "strict" as the PH folks.
- JamesSwift 4y ago
  In general theres two kinds of ways to meet code: by design or by test. They might be referring to a 'design' stipulation which wouldn't require a real test. If they choose to be tested instead, then the 'open when activated' would likely pass. EDIT: it looks like the terms are 'Prescriptive' and 'Performance'. e.g. https://www.energycodes.gov/sites/default/files/2019-09/EnergyCodeCompliancePaths.pdf https://www.energycodes.gov/sites/default/files/2019-09/Ener...
dahfizz 4y ago
Can you just settle for a measly A++? Is there an A++++ rating? Seems like a silly system anyway.
- maccard 4y ago
  Assuming you're joking about the ++'s on the end, the reality is that the efficiency scales (like the appliance energy efficiency scales in europe) were designed when what was considered "good", was vastly different to what it is now. The choice is to either rebalance/demote everyone who built a top rated property 25 years ago, or add more tiers. Political will means we do the latter.
  - dahfizz 4y ago
    Why can't we just use numbers? "This house in this climate will use about X kwh per year for heating/cooling". That's what appliances do. No messing with scales and tiers and having to constantly re-balance. It's also more directly meaningful to customers. An A+++++ mansion is going to use more energy to heat than a modest A+++ house.
    - maccard 4y ago
      > Why can't we just use numbers? Because numbers require everyone who is involved in comparing options (i.e. consudmers) to have intimate knowledge of what those numbers mean. Is X kwh actually good? How does it compare to other houses in the area? What number do you use - the amount of energy it will take to heat the house, or the amount of energy of a specific type you will use. How do you compare those (a house with Natural Gas as a heat source will require significantly less electricity to heat than a house with electric radiators, but will likely _cost_ more). Using ratings gives a standardised way to compare them. If you compare two houses, one has an A rating and one has a B rating, the B one is strictly worse, by an amount that someone who knows something about this has deemed significant. > That's what appliances do Appliances are graded on a similar score here. Every appliance you buy in the EU has one of these [0] labels (which has the same problem). > An A+++++ mansion is going to use more energy to heat than a modest A+++ house. You're comparing two different things here, and forgetting a very important point - someone who is going to buy a "mansion" is not going to buy a modest house, so it doesn't matter what the rating of the house is in comparison. What matters is the rating of the mansion next door. [0] https://en.wikipedia.org/wiki/European_Union_energy_label https://en.wikipedia.org/wiki/European_Union_energy_label

by brnt 4y ago

fnomnom 4y ago

there are a lot of available ventilation solutions that recover the energy and cycle air in your use. they start at 200€ a unit and go up from there. i think the modern cooking extractors are all built into the countertops and just filter the air. at least thats the trend in germany

brnt 4y ago
The point is that those systems do not integrate with extractors, and filtering only removed VOCs and particulates, not water vapour, which you would prefer to extract as well. Heat recovery from an extractor (eg remove heat from air before expelling) would achieve the goal the rating is aimed at, without compromising indoor air quality by not having a way to remove humidity. Or maybe another kind of integrated dehumidifier that discharges in your sink/plumbing maybe. Those filter-only extractors won't do for anyone serious about indoor air quality.
- fnomnom 4y ago
  yeah but in my opinion in modern homes this is automated and regulated house-wide with the mentioned air circulators that recover the energy. they also expell humidity afaik
  - brnt 4y ago
    You'll still have to accept an hour or so of elevated humidity. I prefer not to.

nice__two 4y ago

Berbel has a unit that opens when using the unit and closes, when not in use. Quite ingenious, if you ask me. [1]: https://www.berbel.de/dunstabzuege/zubehoer/abluft-zubehoer/mauerkasten/ https://www.berbel.de/dunstabzuege/zubehoer/abluft-zubehoer/...

brnt 4y ago
That's clever, but this [1] is already common and I guess not much worse? [1] https://www.ventilatieshop.com/terugslagklep-in-ventilatiekanaal-150mm/ https://www.ventilatieshop.com/terugslagklep-in-ventilatieka...
- nice__two 4y ago
  It is much worse. The Berbel retains the insulation provided by the wall, when closed. This is nothing more than a fancy hole in the wall. Opening and closing, means you get the best of both worlds.

throw0101a 4y ago

> For an A+++ energy rated house, you can't have holes in walls where I live. That means you can't have cooker extractors that extract, you can only have them run the air through a filter. It's possible to install dampers that are normally closed for airtightness, but open when the kitchen vent is activated (both on the exhaust, and makeup air, side of things): * https://www.greenbuildingadvisor.com/article/makeup-air-for-kitchen-exhaust https://www.greenbuildingadvisor.com/article/makeup-air-for-... Even the Passive House folks are fine with this arrangement (§3.4): > When the exhaust air system is not operating the exhaust air and intake air vents should close airtight and should not cause any leakage volume flow. Furthermore, additional insulation will be advantageous at these locations. * https://passiv.de/downloads/05_extractor_hoods_guideline.pdf https://passiv.de/downloads/05_extractor_hoods_guideline.pdf So I'm not sure why your building codes mandate recirculation, since I'm guessing even they wouldn't be as "strict" as the PH folks.

JamesSwift 4y ago
In general theres two kinds of ways to meet code: by design or by test. They might be referring to a 'design' stipulation which wouldn't require a real test. If they choose to be tested instead, then the 'open when activated' would likely pass. EDIT: it looks like the terms are 'Prescriptive' and 'Performance'. e.g. https://www.energycodes.gov/sites/default/files/2019-09/EnergyCodeCompliancePaths.pdf https://www.energycodes.gov/sites/default/files/2019-09/Ener...

dahfizz 4y ago

Can you just settle for a measly A++? Is there an A++++ rating? Seems like a silly system anyway.

maccard 4y ago
Assuming you're joking about the ++'s on the end, the reality is that the efficiency scales (like the appliance energy efficiency scales in europe) were designed when what was considered "good", was vastly different to what it is now. The choice is to either rebalance/demote everyone who built a top rated property 25 years ago, or add more tiers. Political will means we do the latter.
- dahfizz 4y ago
  Why can't we just use numbers? "This house in this climate will use about X kwh per year for heating/cooling". That's what appliances do. No messing with scales and tiers and having to constantly re-balance. It's also more directly meaningful to customers. An A+++++ mansion is going to use more energy to heat than a modest A+++ house.
  - maccard 4y ago
    > Why can't we just use numbers? Because numbers require everyone who is involved in comparing options (i.e. consudmers) to have intimate knowledge of what those numbers mean. Is X kwh actually good? How does it compare to other houses in the area? What number do you use - the amount of energy it will take to heat the house, or the amount of energy of a specific type you will use. How do you compare those (a house with Natural Gas as a heat source will require significantly less electricity to heat than a house with electric radiators, but will likely _cost_ more). Using ratings gives a standardised way to compare them. If you compare two houses, one has an A rating and one has a B rating, the B one is strictly worse, by an amount that someone who knows something about this has deemed significant. > That's what appliances do Appliances are graded on a similar score here. Every appliance you buy in the EU has one of these [0] labels (which has the same problem). > An A+++++ mansion is going to use more energy to heat than a modest A+++ house. You're comparing two different things here, and forgetting a very important point - someone who is going to buy a "mansion" is not going to buy a modest house, so it doesn't matter what the rating of the house is in comparison. What matters is the rating of the mansion next door. [0] https://en.wikipedia.org/wiki/European_Union_energy_label https://en.wikipedia.org/wiki/European_Union_energy_label