As a Professional Engineer I have to take 30 Hours of official Continuing Education Courses (CEU)s in order to renew my license. I attend a lot of webinars but not all of them give official CEUs. My state, NH, gives us a lot of flexibility on course content so my choices are eclectic. I had done a lot of Onsite generation course this past two years and a somewhat low quality electric distribution course but still needed some CEUs. I am mulling over building a new house so I took a Heatspring.com course on Passive Houses in the Real World. It was $190 for 10 hours of CEUs. I have taken courses from them in the past,some paid, some free and in general they are usually good quality interesting courses. There are CEU mills that churn out courses (like the electric distribution course turned into) but I actually like learning something. Note the Heat Spring courses require putting in the hours so if someone just needs the hours there are better spots to go to.
So Passive House (occasionally referred to as Passivhaus) is one of the gold standards for home construction. A certified Passive House is built to require minimal heating and cooling while maintaining healthy air quality with the majority of the heat coming from direst solar heating. The concept originally was formalized in Germany and the US followed the German Passive House Institute rules but at some point the US broke off with its own version. The types of construction differ in the US with a lot more climate variation in the US than in Germany with a different approach to construction, so it's tuned a bit better to the US. Both have formal certification rules that start long before the start of construction. It's a complex process with cost and schedule increases but in the end the house really can almost run by itself with no supplemental heating even in cold climate areas. The course has several examples of homes without power that run through a week of winter weather with no power.
Passive Houses sometimes gets linked to LEED certification (Leadership in Energy and Environmental Design) There are some similarities but there are differences in that LEED takes into account sustainability for the entire construction process and materials while Passive House sticks to ultra low energy requirements and high indoor air quality. LEED tends to be a bit "flashier"while Passive House tends to ensure that the techniques used to build the house ensures its going to be low energy high air quality structure. There have been a few media articles about poorly performing LEED buildings that worked when they were built but very rapidly the complexity of the building meant that the savings were not sustained.
Build a certified Passive House and your days of being a wood burner are probably over. Wood stoves are problematical at best as the methods used for post construction certification would not deal well with a wood stove. My speculation is if you really wanted one it would have to be truly sealed total combustion air and flue system and its probably best an off the record design component installed after the certification plaque is screwed on the wall
These builds get most of their heat from the sun using very high-performance windows (mostly European) they make a typical Anderson window look like bargain basement windows. Just as important as the windows is house orientation and window orientation. If someone does not have control of their southern solar horizon for possible shading they will have tough time getting a Passive House certified. In the case of shading, the homeowner may need to settle for Zero Net Energy home and use solar and net metering to make up the loss of heat from the sun in the building. Note they also appear to skip some active measures of energy savings that a dedicated homeowner may consider as they require the homeowner to actively manage a system like cellular blinds with side tracks. Yes they do need to be opened when the sun it out and closed when its not but that means the windows just need to be even more expensive.
The construction of these homes is not something a typical tract home builder is going to pop out. It just requires way too much detailing during construction and specialty subs that can perform to high standard. A case of caulk and spray foam will probably never be able to meet the standard. In order to use the sun in cold climates the minimal net energy received from the sun in winter means the insulation has to be deep in the walls floors and ceilings. Some numbers were R50 walls, R 96 ceilings and 8 to 12 inches of foam in the slabs. The R values are calculated actual values and thermal bridging of structural components has to be avoided. This can get quite complex in framing, and moisture management in the walls and ceilings can be a big issue. Do it wrong and it could be time bomb in the walls that may not appear for years. Previous low energy construction in the 80s and 90s had many of these time bombs that unfortunate folks have had to deal with. One thing that was not a surprise to me was some photos of spray foam insulation failures as my house has some areas where it was applied in an energy retrofit where it pulled off of the joists. My stuff is not covered but these failures occurred over months and seasons so with a typical home, the owner would be unaware that they had defects that could lead to the house having internal rotting issues over the long term.
A very interesting course that made me think but up front I do not think a certified Passive House is in my future or many other's futures. These are mostly one off buildings backed up by architects, certified Passive House Consultants, third party certifiers both off site and on site and final performance testing. Great if someone is a lottery winner or just is willing to pay a premium but my guess is I will use Passive house inspired techniques especially for air sealing and air quality but living up in rural area assembling a team of experts is just not viable unless I want to pay a lot of travel time and mileage. There will be a big portion of DIY on my new home and I would be in no rush so I could take my time to air seal and use advanced framing and probably buy some very expensive windows. I would use a blower door test to test its airtightness before the drywall goes up and integrate heat recovery ducting and a HRV unit into the house design. In my case I would probably take a bit more heat loss and net metered ground mounted solar panels to make it a zero net energy home and maybe even move one of my solar hot water heaters onto the new house. I am unsure I would go with wood heat for the house which means my Tarm boiler would at best be a shop heater for what I believe will be a very large shop.
So Passive House (occasionally referred to as Passivhaus) is one of the gold standards for home construction. A certified Passive House is built to require minimal heating and cooling while maintaining healthy air quality with the majority of the heat coming from direst solar heating. The concept originally was formalized in Germany and the US followed the German Passive House Institute rules but at some point the US broke off with its own version. The types of construction differ in the US with a lot more climate variation in the US than in Germany with a different approach to construction, so it's tuned a bit better to the US. Both have formal certification rules that start long before the start of construction. It's a complex process with cost and schedule increases but in the end the house really can almost run by itself with no supplemental heating even in cold climate areas. The course has several examples of homes without power that run through a week of winter weather with no power.
Passive Houses sometimes gets linked to LEED certification (Leadership in Energy and Environmental Design) There are some similarities but there are differences in that LEED takes into account sustainability for the entire construction process and materials while Passive House sticks to ultra low energy requirements and high indoor air quality. LEED tends to be a bit "flashier"while Passive House tends to ensure that the techniques used to build the house ensures its going to be low energy high air quality structure. There have been a few media articles about poorly performing LEED buildings that worked when they were built but very rapidly the complexity of the building meant that the savings were not sustained.
Build a certified Passive House and your days of being a wood burner are probably over. Wood stoves are problematical at best as the methods used for post construction certification would not deal well with a wood stove. My speculation is if you really wanted one it would have to be truly sealed total combustion air and flue system and its probably best an off the record design component installed after the certification plaque is screwed on the wall
These builds get most of their heat from the sun using very high-performance windows (mostly European) they make a typical Anderson window look like bargain basement windows. Just as important as the windows is house orientation and window orientation. If someone does not have control of their southern solar horizon for possible shading they will have tough time getting a Passive House certified. In the case of shading, the homeowner may need to settle for Zero Net Energy home and use solar and net metering to make up the loss of heat from the sun in the building. Note they also appear to skip some active measures of energy savings that a dedicated homeowner may consider as they require the homeowner to actively manage a system like cellular blinds with side tracks. Yes they do need to be opened when the sun it out and closed when its not but that means the windows just need to be even more expensive.The construction of these homes is not something a typical tract home builder is going to pop out. It just requires way too much detailing during construction and specialty subs that can perform to high standard. A case of caulk and spray foam will probably never be able to meet the standard. In order to use the sun in cold climates the minimal net energy received from the sun in winter means the insulation has to be deep in the walls floors and ceilings. Some numbers were R50 walls, R 96 ceilings and 8 to 12 inches of foam in the slabs. The R values are calculated actual values and thermal bridging of structural components has to be avoided. This can get quite complex in framing, and moisture management in the walls and ceilings can be a big issue. Do it wrong and it could be time bomb in the walls that may not appear for years. Previous low energy construction in the 80s and 90s had many of these time bombs that unfortunate folks have had to deal with. One thing that was not a surprise to me was some photos of spray foam insulation failures as my house has some areas where it was applied in an energy retrofit where it pulled off of the joists. My stuff is not covered but these failures occurred over months and seasons so with a typical home, the owner would be unaware that they had defects that could lead to the house having internal rotting issues over the long term.
A very interesting course that made me think but up front I do not think a certified Passive House is in my future or many other's futures. These are mostly one off buildings backed up by architects, certified Passive House Consultants, third party certifiers both off site and on site and final performance testing. Great if someone is a lottery winner or just is willing to pay a premium but my guess is I will use Passive house inspired techniques especially for air sealing and air quality but living up in rural area assembling a team of experts is just not viable unless I want to pay a lot of travel time and mileage. There will be a big portion of DIY on my new home and I would be in no rush so I could take my time to air seal and use advanced framing and probably buy some very expensive windows. I would use a blower door test to test its airtightness before the drywall goes up and integrate heat recovery ducting and a HRV unit into the house design. In my case I would probably take a bit more heat loss and net metered ground mounted solar panels to make it a zero net energy home and maybe even move one of my solar hot water heaters onto the new house. I am unsure I would go with wood heat for the house which means my Tarm boiler would at best be a shop heater for what I believe will be a very large shop.
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