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.
Have you ever actually tried to put a group of ducks in a row?
That is how the last week has felt, although things are coming together nicely and the next few weeks should move quickly.
Our final window has arrived and will be put in place this week. It is one of the windows on the side of the garage, so it hasn't slowed us down. The temporary doors should be here very soon as well.
The poly has been placed in the basement on top of the gravel and inspected. On top of that will be 4 inches of foam insulation, and then 4 inches of cement over that.
This was planned for last week. Unfortunately that duck didn't want to line up in a row and we ended up with the incorrect insulation.
Fortunately, our guys were right on top of it and the correct insulation was delivered Friday. We are working on getting back on the schedule to have it installed, hopefully, next Monday. Once installed the radiant tubing will be placed/stapled to the foam and we will be running an in-floor conduit for an outlet under our gaming table.
I'd like to share something I learned about this insulation as I never had thought about this before.
There are two general ways to produce this stiff foam insulation.
We are using Expanded Polystyrene (class 9) which is white in color.
The other type is Extruded Polystyrene, typically blue or pink in color.
The R-Value (the higher the R value the better an insulator it is) is very close (4.4/inch vs 5/inch) and the compression value (25 PSI) is the same as the typical Extruded foam insulation.
The Expanded Polystyrene (EPS) is made by taking small plastic beads and filling them with air. This is done using steam.
98% of the volume of EPS is air. After the useful life (many decades, if not centuries) the EPS can be recycled and used again as insulation, packaging, etc.
The Extruded Polystyrene (XPS) uses polystyrene crystals. A blowing agent is then added and fed into an extruder where the mixture is melted into a plastic ooze. The blowing agent used are an interesting mix of chemicals. As these off-gas some are damaging to the ozone, some are greenhouse gases and other VOCs.
Another interesting aspect of the XPS is that it looses some of its R-value as it off gases. EPS does not (and any off-gassing is simply air). So while the XPS has a small advantage in R-value when new, the EPS will have a consistent R-value over time.
So, it came down to the fact that the EPS will take less energy to make, use less damaging (locally and globally) chemicals both in the process of making it and as the product off-gasses, and have just as good, if not better insulation value over time.
This week we are finishing up a few inspections, installing the final garage window, and starting to work with our cabinet maker (Jesse) to make sure the kitchen is just right (best laid plans, right:)).
Much of the landscaping, now that the retaining wall is in place, will be waiting for spring. Plans will be polished off over the winter so we will be on the schedule for first thing in the spring.
Oh, and last but not least, I am starting to clean up our current house to get it ready for sale, and cut down on the amount of "stuff" we will be moving (selling, donating or recycling where ever possible). If anyone wants any pictures of wolves, I may have something for you:-)
Mark really doesn't like to talk about himself, the house is much more interesting.