2 ms·

I don't disagree the problem is solved - I the problem in the UK is humidity is quite high most of the time and most houses don't have HVAC and there seems to b

I don't disagree the problem is solved - I the problem in the UK is humidity is quite high most of the time and most houses don't have HVAC and there seems to be a complete lack of knowledge around ventilation - very little thought goes into it for domestic properties, so you send up with these sealed up houses under the guise of "energy efficiency" which makes people ill though mold growth due to lack of air flow. It's probably also contributed to the spread of covid 19.

throw0101a 5y ago
> I the problem in the UK is humidity is quite high most of the time and most houses don't have HVAC and there seems to be a complete lack of knowledge around ventilation Mandating (whole house) dehumidifiers in building codes may help with that if air tightness is also mandated.
blacksmith_tb 5y ago
I live in a Passive House[1] in the equally-humid Pacifc NW, without any kind of dehumidifier. I do have a Heat Recovery Ventilator (HRV) running 24/7, which pulls in fresh air from outside and exhausts indoor air, running them through a heat exchange as they pass each other to save some of the energy that went into the air while it was inside. As a plus it also runs the air through a MERV 13 air filter, which gets rid of pollen and some PM2.5 pollution. 1: https://en.wikipedia.org/wiki/Passive_house https://en.wikipedia.org/wiki/Passive_house
- throw0101a 5y ago
  On the effectiveness of various MERVs on various PM sizes: * https://www.greenbuildingadvisor.com/article/understanding-filter-ratings-merv-fpr-and-mpr https://www.greenbuildingadvisor.com/article/understanding-f... * http://dx.doi.org/10.3390/ijerph120708448 http://dx.doi.org/10.3390/ijerph120708448 * https://www.researchgate.net/figure/Mean-PM-25-removal-efficiency-for-HVAC-filters-listed-by-MERV-classification_fig1_280321614 https://www.researchgate.net/figure/Mean-PM-25-removal-effic... Just make sure your system can handle whatever MERV you go with (higher = more back pressure that needs to be designed for).
  - blacksmith_tb 5y ago
    Yes, I would go higher than MERV13 if I could, my HRV is a Zehnder, which doesn't support better filters without some modifications.
    - throw0101a 5y ago
      Ah yes, it seems that the built-in stuff has restrictions, but there are external boxes that can be added: * https://www.zehnderamerica.com/our_products/comfowell-silencer-and-casings/ https://www.zehnderamerica.com/our_products/comfowell-silenc... Which allow MERV 16 and even carbon filters: * https://www.zehnderamerica.com/product-category/comfowell/ https://www.zehnderamerica.com/product-category/comfowell/ * https://www.youtube.com/watch?v=OrG7oG8Tvp8&t=14m35s https://www.youtube.com/watch?v=OrG7oG8Tvp8&t=14m35s

throw0101a 5y ago

> I the problem in the UK is humidity is quite high most of the time and most houses don't have HVAC and there seems to be a complete lack of knowledge around ventilation Mandating (whole house) dehumidifiers in building codes may help with that if air tightness is also mandated.

blacksmith_tb 5y ago

I live in a Passive House[1] in the equally-humid Pacifc NW, without any kind of dehumidifier. I do have a Heat Recovery Ventilator (HRV) running 24/7, which pulls in fresh air from outside and exhausts indoor air, running them through a heat exchange as they pass each other to save some of the energy that went into the air while it was inside. As a plus it also runs the air through a MERV 13 air filter, which gets rid of pollen and some PM2.5 pollution. 1: https://en.wikipedia.org/wiki/Passive_house https://en.wikipedia.org/wiki/Passive_house

throw0101a 5y ago
On the effectiveness of various MERVs on various PM sizes: * https://www.greenbuildingadvisor.com/article/understanding-filter-ratings-merv-fpr-and-mpr https://www.greenbuildingadvisor.com/article/understanding-f... * http://dx.doi.org/10.3390/ijerph120708448 http://dx.doi.org/10.3390/ijerph120708448 * https://www.researchgate.net/figure/Mean-PM-25-removal-efficiency-for-HVAC-filters-listed-by-MERV-classification_fig1_280321614 https://www.researchgate.net/figure/Mean-PM-25-removal-effic... Just make sure your system can handle whatever MERV you go with (higher = more back pressure that needs to be designed for).
- blacksmith_tb 5y ago
  Yes, I would go higher than MERV13 if I could, my HRV is a Zehnder, which doesn't support better filters without some modifications.
  - throw0101a 5y ago
    Ah yes, it seems that the built-in stuff has restrictions, but there are external boxes that can be added: * https://www.zehnderamerica.com/our_products/comfowell-silencer-and-casings/ https://www.zehnderamerica.com/our_products/comfowell-silenc... Which allow MERV 16 and even carbon filters: * https://www.zehnderamerica.com/product-category/comfowell/ https://www.zehnderamerica.com/product-category/comfowell/ * https://www.youtube.com/watch?v=OrG7oG8Tvp8&t=14m35s https://www.youtube.com/watch?v=OrG7oG8Tvp8&t=14m35s