|
This week, I wanted to share with you one of the motivations for us to build a Net Zero house. There are lots of motivating factors, and one person's motivations may be different from another's. First though, regarding our project, last week was a short week with lots of 'behind the scenes' work and little visual changes. Next week I hope to have much more about the house. Ok, now back to my biggest personal motivator. Climate Change. We are already seeing the effects in our current world. And the impacts are being felt most by those that can least afford it. Scientific organizations around the world, NASA and numerous US Scientific organizations, the Pope's Encyclical, many other religions and religious leaders, the director of the CIA, the Department of Defense, many businesses, insurance companies, advocates of the poor all agree something needs to be done. We have the technology available today to make a difference. And each and every one of us can make a difference. If you are looking to learn about climate change, and I highly recommend you do, there are some great resources available.
Here are some great videos. Richard Alley has a great book called "Earth the Operator's Manual". It is also available as videos. More resources can be found on the Partners & Resources page. Mother Nature definitely let us know just who is in charge. We made great progress in some areas, and setbacks in others. The upstairs drywall is a huge improvement! We still have lots of trim work and finishing to do, but the drywall makes the rooms look sooo much more like actual rooms! It is much easier to get a 'feel' for the spaces. Below is the view of our great room, the doorway leads back to our bedroom.  I get excited every time I see this!
Turns out, they were right, and I am much calmer now. The bulk of the water was gone in a day. We are still drying out the last remnants of it. We also have a tarp on the roof to insure there are no water leaks now that we are putting in drywall upstairs. The work of the plumbers and HVAC systems downstairs will have to wait a bit as we dry out the basement. Work is continuing upstairs, as well as the outside of the house.
This is a short work week, however, the weather should be nicer, so I am hoping to have lots to talk about next week.
I hope everyone has a wonderful Thanksgiving. Talk to you more next week! This week the garage and causeway, between the garage and house, had their concrete floors poured. Xcel also hooked up our house meter, the framers were busy downstairs and our water management design for the area at the bottom of the retaining wall got a trial run. The concrete pour was a pretty cool process which I got to watch some of (while staying out of the way of course). One note, concrete is not very environmentally friendly in that it takes a lot of nasty stuff to make. As a building material, however, it has lots of advantages. To increase the recycled content of the concrete, as well as strengthen in, the concrete we are using contains "fly ash". Fly Ash is actually a waste product from burning coal (yuck). While I personally hate the idea of burning coal, using some of the fly ash that is being stored (coal plants can't simply let it free in the air or dump it anymore) means not as much material needs to be mined and made into the old standard Portland Cement. By adding fly ash, the end result can also be stronger and more durable. The ancient Romans actually used volcanic ash, which is similar to fly ash, in their concrete. This is part of the reason for the durability of their structures. We also are making a home for a 'built in' mat. Similar to many mats/grates you may see at banks, offices or other commercial buildings. These mats help maintain healthy indoor air by scraping off shoes of debris. With the small depression, the mat won't go sliding around and people won't trip on it (I do that a lot with our current one). To create the half inch depression, a very painstaking, unforgiving, stressful process was involved. A 4x4 sheet of plywood was wrapped in plastic and pushed into the fresh concrete ;-) Far easier than doing it after the concrete set. We will be doing the same on our front step (with narrow channels for water to drain). Xcel came out this last week and trenched a 4-5 foot deep path for power to our house. Power is live now to our meter, although we don't yet have the basement and mechanical room done. Once that is done, we should have power available to our own lights and switches! Their timing was perfect, because the next day we got two inches of rain. That would not have been a fun job after that. We currently are set up with Xcel's Windsource program, so our power at the temporary meter out by the road is offset by wind power. Once our solar panels are up, we will continue using Xcel's Windsource power, however, we will also be sending as much solar energy into the grid as we draw from it.
Framing has begun downstairs! We can now start to see the design and layout of the rooms, which made us very happy. Every week we get closer and closer to our dream:) We also had a chance to see the drain tile down in the retaining wall in action. After a couple of inches of rain the area by the walls are dry and the little "retaining pond" is doing its job holding the water as it soaks into the ground. This coming week it is raining pretty much all day Monday and Tuesday, so this will be another good test for it. This coming week we will be finishing up with the framing and insulation downstairs. Plumbers, HVAC and electrical work will also be going on downstairs.
Drywall will start going up on the main floor and the final door (temporary doors) will be put in place. Once the drywall is on the walls, we will be insulating with additional cellulose insulation. I am not sure if that will get started. We also have the guys working on the siding. With the weather, I am not sure if they will be a bit delayed or not. 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. Visually, not much happened this week. Lots of 'behind the scenes' work to prepare for this week. So, I figured this was a good week to talk about cars! Let me ask you to consider a car that... Has more room in it for the same exterior size. Magically fills itself so you have a full tank every morning. Has lower maintenance. Has a higher quality ride (quiet, smoothness) as other cars at the same price point. Has more performance (acceleration, stability, instant throttle response, to "gear lag" when shifting). Is safer to drive. Can be preheated in a closed garage with ZERO fear of CO poisoning. Oh, and fuel costs between half and a quarter of what you pay now. "Now wait", you may be thinking, "what is the catch"? The drawbacks are that you have to spend about 10 seconds to start the overnight fill-up and the 'gas tank' is sized to give you a daily range of 100-200 miles. If you drive further than that, refilling in the middle of the day can take 20-60 minutes. Yes, many of you may have guessed, that describes both my wife's and my car. They are electric cars and they are available now.  At this early stage (about 1% of the cars sold this year in the U.S. are electric) it is very convenient if you have a reliable place to plug in at home or at work.
Many families I know have one electric car and a gas guzzler for trips, although I know of a number of families where both cars are electric. In our case, we also drive electric because it allows us to decide how "clean" the cars are. The CO2 footprint of fueling the cars is as low as we want it (and we want it to be very low). In addition, the fuel is all regional. Most generated in Minnesota, some in bordering states. This puts our money to use in our local economy rather than elsewhere in the country or world. And for every kWh of electricity we use from the grid to charge our cars, we will be sending a kWh of electricity generated by our solar panels back into the grid. As the mayor of Indianapolis, Greg Ballard, said at a Fresh Energy event in Minneapolis a few months ago, "Do you want to support our troops? Drive an electric car." (more information about his city's electric car plans here). Tying this back into our house, we never would have had the opportunity to produce as much energy as both our house and both vehicles use, if the cars used gasoline. The reason for that is gasoline cars are very inefficient. A friend of my refers to cars with internal combustion engines (ICE) are great heaters, that also give you a little bit of propulsion. Gasoline is a very energy dense way to store energy. One gallon of gas has the same amount of energy as 33.7kWh of electricity. The problem is an ICE is between 20%-35% efficient. You can think of it this way, for every $20 of gas you put in your car, $13-$15 of that is going into making heat. In Minnesota, in the winter, that is wonderful as you will make use of a few dollars of that heat (and throw away the rest). So, in order to produce as much power (converted from gallons of gas into kWh) with our solar panels, we would need about a 45kW solar array. That is about 150 panels. Our planned system is 18kWh (~9kW for the cars and 9kW for the house). We don't have room for more than a couple more panels, certainly not the extra 80-90 we would need. So, in closing, let me just say that due to electric cars (not to mention mower); we haven't needed to buy gasoline in over two and a half years, are within reach of our dream of owning a house that provides all the energy both our cars and house use on an annual basis, and have had the best driving experience I have ever had. This week we have lots of activity going on at the house, and I am looking forward to showing you all the changes. |
