Specifically with insulation, have you had trouble with air exchange?
I keep hearing (to my naive/inexperienced/non-builder mind) contradictory advice about how insulated houses should be, and I've been trying to figure out how to square decreasing heating/cooling costs with keeping a house from feeling stuffy.
I guess for stuff like the triple glazing that's not really affecting air exchange in the first place, it's just preventing energy loss, since you're already not doing air exchange through your wall. And maybe getting better insulation in walls means you can crack open a window without it being as much of a problem?
Modern construction standards like Passive House call for an extremely well insulated and air tight building envelope. Because you're no longer losing conditioned air to drafts, they then use a system that constantly brings fresh air from outside, runs it through a heat exchanger to extract most of the heat (or cool, and in some cases moisture) from the conditioned air before it's exhausted. Generally you constantly pump fresh air into the living areas and bedrooms and exhaust air from the bathrooms and kitchen (places with lots of moisture and smells).
This is very important. But there’s a good solution (last paragraph).
Our old house, built in the 1920s had been basically sealed. Since it was only 1600 sqft and had no air ducts, the rooms were small and got terribly icky. Id crack the window open in the winter to get rid of the humidity (in PA, so hardly mild winter).
You have to realize that a lot of moisture from those those 8 tall glasses of water you’re supposed to drink leave your body as vapor. I think I’ve read half the water you expel is through your lungs [citation needed]?
If your house is sealed this water has no where to go. If there’s four of you it gets bad very quickly. This moisture eventually will escape through your drywall, into your insulation and finally through the cracks of tour siding; but that means materials that should be kept dry aren’t
Our new house is very drafty and I dont plan to fix that until I instal a heat exchanger. The air in the new house is much better, and despite being at least double in size our bills have only doubled (ie the added draftiness doesn’t seem to have had that big an effect)
The solution is a heat exchanger. This is a device that exhaust stale air and replacing it with fresh air while passing through a heat exchanger. You can have very large air flows with the outside almost free energetically.
As I understand it -- In a passive house you exchange air with an always-on air exchanger (HRV or ERV depending on your climate) which also has filters.
Specifically with insulation, have you had trouble with air exchange?
I don't have empirical evidence, however I am pretty sure that we have reasonable air exchange. My evidence for this is threefold:
1) when we have used the log fire, it didn't kill us, or pull the door open.
2) there is still a slight draft,
3) we have a missing floorboard in the understairs cupboard
Whilst all of the air bricks in the rooms were covered, the suspended floor still has four bricks exposed. The triple glazing is sealed UPVC, however in the loft conversion we were forced to have trickle vents (I think thats overkill)
It doesn't ever feel stuffy, which is good. I do need to get a real CO2 monitor though.
One last bit of evidence is how quickly particulates from cooking disappear
I think houses often have air to air heat exchangers. They suck in air from the outside, and through the power of physics somehow warm it up or cool it down to match the room temperature.
Comments
Specifically with insulation, have you had trouble with air exchange?
I keep hearing (to my naive/inexperienced/non-builder mind) contradictory advice about how insulated houses should be, and I've been trying to figure out how to square decreasing heating/cooling costs with keeping a house from feeling stuffy.
I guess for stuff like the triple glazing that's not really affecting air exchange in the first place, it's just preventing energy loss, since you're already not doing air exchange through your wall. And maybe getting better insulation in walls means you can crack open a window without it being as much of a problem?
Modern construction standards like Passive House call for an extremely well insulated and air tight building envelope. Because you're no longer losing conditioned air to drafts, they then use a system that constantly brings fresh air from outside, runs it through a heat exchanger to extract most of the heat (or cool, and in some cases moisture) from the conditioned air before it's exhausted. Generally you constantly pump fresh air into the living areas and bedrooms and exhaust air from the bathrooms and kitchen (places with lots of moisture and smells).
This is very important. But there’s a good solution (last paragraph).
Our old house, built in the 1920s had been basically sealed. Since it was only 1600 sqft and had no air ducts, the rooms were small and got terribly icky. Id crack the window open in the winter to get rid of the humidity (in PA, so hardly mild winter).
You have to realize that a lot of moisture from those those 8 tall glasses of water you’re supposed to drink leave your body as vapor. I think I’ve read half the water you expel is through your lungs [citation needed]?
If your house is sealed this water has no where to go. If there’s four of you it gets bad very quickly. This moisture eventually will escape through your drywall, into your insulation and finally through the cracks of tour siding; but that means materials that should be kept dry aren’t
Our new house is very drafty and I dont plan to fix that until I instal a heat exchanger. The air in the new house is much better, and despite being at least double in size our bills have only doubled (ie the added draftiness doesn’t seem to have had that big an effect)
The solution is a heat exchanger. This is a device that exhaust stale air and replacing it with fresh air while passing through a heat exchanger. You can have very large air flows with the outside almost free energetically.
As I understand it -- In a passive house you exchange air with an always-on air exchanger (HRV or ERV depending on your climate) which also has filters.
I don't have empirical evidence, however I am pretty sure that we have reasonable air exchange. My evidence for this is threefold:
1) when we have used the log fire, it didn't kill us, or pull the door open.
2) there is still a slight draft,
3) we have a missing floorboard in the understairs cupboard
Whilst all of the air bricks in the rooms were covered, the suspended floor still has four bricks exposed. The triple glazing is sealed UPVC, however in the loft conversion we were forced to have trickle vents (I think thats overkill)
It doesn't ever feel stuffy, which is good. I do need to get a real CO2 monitor though.
One last bit of evidence is how quickly particulates from cooking disappear
I think houses often have air to air heat exchangers. They suck in air from the outside, and through the power of physics somehow warm it up or cool it down to match the room temperature.
Found this while searching: https://www.ag.ndsu.edu/publications/energy/air-to-air-heat-...
You can always consider installing an ERV to provide fresh air inside the house with minimal energy loss.