Last week was wonderful!
Our entire main floor is being tiled, and it was almost completely done in that one week! ...
With the warm weather last week, our new friend is now a single, rather than double snowman. It is a little tough to tell, however he is still smiling!
At the end of last week the tubing for the radiant heat was laid down. This will be our heat source when the passive solar design needs some help.
Tis the season for Minnesotans to start layering up for winter, and our house is no different.
The foam insulation that was delivered last week was installed downstairs.
The edges were then taped or spray foamed for a tight seal.
After that was done, our radiant heating tubes were methodically laid out and stapled to the top layer of foam.
All of the radiant tubes are gathered in one place in the mechanical room.
Until we have walls, they have a temporary 'home' as seen in the second photo.
They won't be lonely for long though, as more radiant heating tubes will be going in upstairs.
This last week we also had spray foam insulation being applied to nooks and crevices upstairs. Air barriers were also applied to the inside of the walls after the spray foam.
Holes have been drilled along the top of the walls, in the house, so the cellulosic insulation can be blown in at a high pressure (for the best long term performance).
The guys from Kinzler had recently just finished another net zero home. In that home, they blew in the cellulose at a high pressure prior to the drywall being installed. This is the typical order.
The only issue with doing it in this order, they discovered, was that the drywall guys had to get four guys to get each section of the drywall flat against the frame of the wall!
They recommended we install the drywall first, so the drywall guys wouldn't send us a lump of coal for Christmas ;-)
We happily learned from their experience and agreed that we want this to run as smoothly as possible for everyone, so we will be installing the drywall first, and then blowing in the cellulose.
The garage, and the causeway, between the garage and the house, are a different matter though. These areas are not heated and don't have as much insulation. Thus it will be much easier to apply the drywall after the cellulose is blown in.
In those areas, they stapled a material over the frame of the walls and blew in the cellulose. I have pictures above of the prepped areas and then the same areas after the blown in insulation.
The insulation bulges out a bit, but is easy to push flat. For these areas, the guys cut a hole in the membrane and blew the cellulose in. You can see these in a couple of the photos.
Using the tube, they would start at the bottom and work their way back up. Then, move the tube to the top and work their way back again.
They were also nice enough to ask me if I wanted to give it a try!
Next week, I'll take them up on that when we do some of the insulation in the house. I am very much looking forward to it.
I find it very satisfying to play a small role in helping with the house, as long as I can stay out of the way of the experts.
Also shown above, is a close-up of the insulation itself.
This stuff is wonderful. It is made up, almost completely of recycled content.
Recycled newspapers, shredded fabric, even shredded up credit cards. It also does a really good job as insulation.
Per inch of thickness it isn't as good an insulator as the spray foam. However, it takes much less energy to make, uses recycled products, and is not toxic (when installing the spray foam the guys wear full body suits and a rebreather).
Because it is blown into areas, it doesn't do a great job filling in corners and crevices, which is why we use the expanding spray foam in areas like that. It will expand to fill even the smallest crevice.
This is also one of the reasons a simpler exterior wall structure is more environmentally friendly. The more recycled cellulose vs expanding spray foam, the better.
On the outside of the house, all those geothermal tubes sticking up out of the ground have now been buried.
The guys dug down six feet and connected the fourteen, 110 foot wells in seven pairs. Those were then connected to a single return tube which can be seen in the third photo entering the house.
Both our domestic hot water and HVAC system run off the geothermal.
Rather than separate wells for hot water and HVAC, with a single source, if only one of the two systems are running, it can gather heat from all the wells.
At the end of last week, we had a bunch of tubes sticking up through a very sloppy mess. Now, nothing is visible and the back yard, while not exactly pretty, just looks like dirt, rather than a swamp.
And then, and I can't exactly explain it, the thing that made me happiest this week happened...
The guys poured our cement floor in the basement!
Yes, we actually have a floor down there now. It feels soooo much better having a concrete floor rather than rocks.
In a couple of the photos you can see the concrete doesn't go all the way to the walls. This was done by placing 2"x4"s along the wall, and then expanded foam inside the wood.
The wood will be removed, and the foam cut to be even with the concrete surface (the foam will be removed if it doesn't cut evenly). The gap will then be filled with spray foam (again, for its superior insulation value).
We will be polishing the concrete which will act as more thermal mass for us. With the radiant floors, we expect it to be very comfortable down there.
Also added to the concrete are devices called "Zip Strips". These basically "encourage" the cracks in the concrete to follow the zip strips. It won't make it crack any faster. But when it does, it will crack where we want it to rather than some random location.
Since the polished concrete will be our floor, this is especially important. Much of the path of the cracks will be under walls, or other areas that are less noticeable.
I'll try to get some photos of these for next week.
Currently, we are planning on a February or March completion date. Earlier we were hoping for January. However, little delays here and there tend to add up and cause other rescheduling issues.
While we are very eager for the house to be complete, it is even more important that it be done right.
I also do not mind at all, the idea of moving in March rather than January!
The garage and causeway will be poured this week (today actually) and lots of other goodies are in store for next week.
In the photo above, you may have noticed the awning that extends out from the edge of the house a bit. This is there to provide shade to the windows when the sun is high in the sky in the summer, yet not block the sunlight during the winter when the sun is lower in the sky.
With our concrete and tile floor, we will absorb that warmth, freely provided by the sun, into the thermal mass of the floors.
This helps the house not heat up as much during the day, and the concrete/tile will release that heat overnight when it is cooler.
Effectively, with careful placement of windows and awnings, we lessen the need for mechanical heating and cooling. Lowering the energy the house uses to stay comfortable and making it easier for us to produce as much energy as we use over a year.
Of course, you can also do this without any solar panels or such, simply to lower your heating and cooling bills.
Next week's blog should have lots of activity, as long as the rain holds off long enough to get the waterproof roof membrane installed!
I like to say our home produces power from the safest fusion generator possible -- which is about 93 million miles away and at the center of our solar system!
The drawing above, of our house as designed, is from Marc Sloot, our architect at SALA.
We produce that power using solar panels and they're great in so many ways: They have no moving parts. The fuel to generate power is free. There are no toxic fuel spills.
But let's be honest - there are drawbacks. Since the sun doesn't always shine, power generation isn't 100% steady. This means, if you're not ok with power fluctuations, you'll need to have a backup plan which stores energy to use when the sun isn't shining. One way is a battery backup.
A more typical backup plan (which we use) is connect to the electrical grid. Here's how it works: When the sun's shining we generate electricity. When the sun's not shining, we draw from the grid. And, another bonus: if we generate more than we use, we "send it back" (i.e. send it into the grid) to help power our neighbor's homes.
While we are designing the house to send as much energy to the grid as we draw over the year, we want to support a cleaner electrical grid so we will be subscribing to Xcel Energy's Windsource program.
Our system is 18.6kW in power generation, comprised of 61 LG 305-watt panels.
Our southern exposure for the panels is wonderful. Almost completely shade free.
Mark really doesn't like to talk about himself, the house is much more interesting.