Blogs - Mill Creek Net Zero Home

Blogs - Mill Creek Net Zero Home Category

Foundation Walls

November 20th, 2008 by Conrad in Blogs - Mill Creek Net Zero Home, Energy Conservation, Green Building Blogs, Green Homes

The MCNZH foundation. The rectangle that’s jutting out is the cold room, located under the front steps/landing.

A frequently asked question regarding the Mill Creek NetZero Home (MCNZH) is: “Why didn’t you use Insulated Concrete Forms (ICFs) for the foundation walls?”. The short answer is: “using traditional concrete forms and innovative insulating techniques, we can achieve a much higher R-value for less money”.

ICFs are concrete forms made of styrofoam that you set up, pour concrete into, and leave in place to act as insulation. Here’s a picture of someone setting them up:

The advantages of ICFs include decent insulation value, ease of learning for the do-it-yourselfer, and ease of setup (foam is a lot lighter than plywood).

There is a myth that ICFs provide walls with an “equivalent energy loss performance” to an R 50 wall. The argument goes that the mass inside of the concrete walls acts as heat storage, thereby buffering heat as it goes in and out of the building. The counter-argument is quite complex, but suffice to say that I’ve heard very knowledgeable people say that ICFs performing like an R 50 wall is complete bunk. The argument makes sense, too. When it’s minus 20 outside, the relatively small amount of thermal energy stored in a concrete wall will have little effect. R value is R value. ICFs provide about an R 22 wall, with no thermal bridging. That’s pretty decent, but it’s not R50.

The foundation walls for the MCNZH will be insulated to about R 49 - actually R 49, no caveats or stars beside that term. We had the walls poured conventionally - with plywood forms - in August (see picture at the top), and before we poured the basement slab Peter Amerongen’s crew glued 5 inches of ozone-friendly foam against the inside of the foundation walls. That will provide R 22. Then, we had interior walls (called frost walls) framed along the foundation walls, 7 inches away from the foam. When the cavity between the foam and the frost wall is filled with cellulose fiber insulation, at R 3.74 per inch, it will add 26.88, for a total R value of 48.88 for the foundation walls, with no thermal bridging. Not too shabby, considering that conventional builders will insulate to R 12, with a full thermal break at each stud. Here are some pictures:

The door opening in the MCNZH’s basement. The foam is glued directly to the concrete (only 2.5 inches here, we ran out of foam, but we’ll add more later), and the frost wall is framed out 7 inches away from the foam.

The window opening in the MCNZH’s basement bedroom (opening still filled with plywood). Here you can see the full 5 inches of foam, with the frost wall framed 7 inches away.

Another view of the frost wall.

This foundation will provide very high energy-saving performance, and it was fairly economical. It should be a very comfortable place for someone to live.

(cross posted at greenedmonton.ca)

MCNZH - The Look

November 4th, 2008 by Conrad in Blogs - Mill Creek Net Zero Home, Green Building Blogs, Green Homes, Uncategorized

MCNZH - from the street (the house faces north)

This is the current color scheme/look of the Mill Creek NetZero Home (MCNZH). The supports for the porch roof will be made of recycled gluelam beams. And of course, we’ll have bicycle parking out front. Eco-travellers are welcome here. Read the rest of this entry »

Isulated Basement Slab

November 3rd, 2008 by Conrad in Blogs - Mill Creek Net Zero Home, Energy Conservation, Green Building Blogs, Living Spaces

The best two things a home builder/renovator can do in the name of energy efficiency is to insulate and seal a house. It’s almost too bad, what with our culture’s obsession with everything high tech. When people ask me about the Mill Creek NetZero Home (MCNZH), they’re often expecting to hear about technology’s magic answers. When I start talking about insulation levels, eyes start to glaze over, but the truth is that 75% of the difference between this house and a conventional one is that it’s sealed as tight as a plastic bag and it’s super-insulated. Read the rest of this entry »

MCNZH - Progress (part 2)

October 24th, 2008 by Conrad in Blogs - Mill Creek Net Zero Home, Green Building Blogs, Green Homes, Reclaimed & Recycled Materials

We have trusses, and we’ll have a roof by tomorrow. Nick and Adam of Green Door Builders are doing a great job of framing the house. Peter is always amazed at how little waste they create. They’re only throwing out little toothpicks of plywood. On top of that they are dipping into a pile of reusable lumber that I set aside for them:

A 2×6 left behind by the cribbing crew (up top, covered with a light coating of concrete) was conscientiously reused during framing

The site that we’ve chosen for this house is a beauty for solar:

The sun bathes the window frames and solar module locations

And let me tell you, we’ll have the windows to collect the sunshine. Here is the view from the future kitchen.

Windows. Big ass windows.

We’re managing what little waste there has been so far by sorting it into piles of scrap metal, burnable wood, reusable wood, and waste wood (pressure-treated and formaldehyde-laced). Next up: the windows and the plumbing.

(cross-posted at greenedmonton.ca)

She’s a Big’n

October 18th, 2008 by andrea in Blogs - Mill Creek Net Zero Home, Green Building Blogs, Green Homes, Living Spaces, Uncategorized

I remember viewing a home on the ecosolar home tour a few years back that had just been expanded to 3000 ft.² plus a full basement. I walked away from that home shaking my head - can we really call 1000 ft.² of living space per person green?

The Mill Creek NetZero Home (MCNZH) is now fully framed, and it’s looking pretty big on the streetscape. We built a pretty big house, and I wanted to document some of the considerations that went into the decisions we made.

The official square footage of the MCNZH is 2280 ft.² With a full basement, that’s 3267 ft.² of living space. For four people, that’s definitely more space than we need. I am not a believer in the “techno-fix”. Technology will not save us from having to make changes to our lifestyle. We will have to considerably scale it down to start fixing the problems that we’ve caused.

So, while I acknowledge that our new home will be luxurious by world standards, here are some of the mitigating factors for its size:

It’s actually only 2064 ft.² of living space by conventional measurements. Because the walls are 16″ thick, we lose 10″ of space per wall versus a regular 2×6 wall.
Once it becomes legal to have suites in our neighbourhood, which should be in December 2008, two thirds of our basement will become a suite. This will increase the population density of the house by effectively making it two houses in one.
The home is being built to “flex” to our needs. Once the children leave, we will be able to quite easily turn the upstairs into a separate suite. This way, there will always be four or more people living on the main and second floors.
This house is a hedge against future uncertainty. I believe that we are going to have to move back to the multi-generational household at some point. Having more room will be better when the tough times hit.
After much deliberation, we decided to add a loft - essentially a half-story - to the home. What put me over the edge in favour of the space was the heat-loss computer modelling that I did. It showed that the extra 306 ft.² from the loft would only cost us 400 kWh per year in heating energy. The flexibility that the extra space gives us was worth it.

I’m sure that we could have cut back on more space somewhere, but when you’re spending your life savings on something it’s tough. The incremental cost to add more square feet is so low once you’re building already…I guess that’s how everyone thinks, and that’s how our houses got so big.

We are very excited to move into the MCNZH. It’s going to be more space than we need, but we’ll try to use it fully and wisely.

(cross-posted at greenedmonton.ca)

MCNZH - Progress (part 1)

October 3rd, 2008 by Conrad in Blogs - Mill Creek Net Zero Home, Energy Conservation, Green Building & Design, Green Building Blogs, Living Spaces

We tore down the house at 9805 - 84 Avenue about 45 days ago, and Peter Amerongen and Habitat Studios have made a lot of progress since.

The very beginning was quite stressful due to some difficult neighbour relations, but we go through that (for now). In the meantime, our foundation is poured and backfilled:

and the framing is well underway:

Adam the framer frames the double-walled exterior walls. Once filled with insulation and sealed, they will provide an amazing R56-rated resistance to heat flow to the outside.

The east and west walls completed, with a pile of reclaimed two-by-fours from the old pink house that Adam and Nick, the framers, will reuse as backing.

Rim detailing: Adam seals the gaps between boards to reduce air movement around the floor rim. This rim would normally remain exposed, leaking air for the entire lifetime of the house.

Adam finishes the rim detail by stapling a strip of Tyvek over the floor rim board. Attention to details like this, which Adam and Nick are very conscientious about, is very hard to come by in Alberta’s slap-it-up-quick building industry trades culture.

The framing is probably the most revolutionary part of this NetZero Home, which is ironic because it adds the least amount of cost compared to the other innovations. Insulation and good sealing have no moving parts - they will save energy 24 hours per day, 365 days per year, and never break.

The second floor should be done by the end of this week!

(Cross-posted at greenedmonton.ca)

Scrap Metal (Part 2)

August 11th, 2008 by Conrad in Blogs - Mill Creek Net Zero Home, Green Building Blogs, Reclaimed & Recycled Materials

Maple Leaf Metals is located at 4510 - 68 Avenue. They are the place to bring scrap metals of all kinds. I had heard that they pay the best money for the scrap, and overall I was happy with my MLM experience.

Last week I borrowed the Habitat Studios truck and loaded up the metallic material that I collected out of the house that stood at 9805 - 84th Avenue.

The two natural gas ranges, furnace, dryer, and hot water heater have no scrap value. That’s probably because they would require some labour to take apart. So I took those to the Eco Station:

Tristan from Habitat Studios is standing in front of the truck. Major appliances are accepted for free at Edmonton Eco Stations

Then I loaded up all the other metals. It’s important to keep the copper somewhat separated, because it’s worth the most. And yes, copper wiring counts, even with the insulating plastic on it.

Galvanized steel water pipes, cast iron drain pipes, natural gas lines, furnace ducting, and most importantly, copper wire and piping.

Off to Maple Leaf Metals:

They inspect the metal that you have, and then direct you into a warehouse if there’s anything worth sorting out. We pulled out the copper wiring and pipes and separated them into bins, because they pay a different rate for each. Then, they weighed the entire truck on a scale, and sent me to the yard. It reminded me of what hell might look like:

I kept expecting one of the yard monsters to begin eating me. I’m always uncomfortable on construction sites - a nerd in a pickup truck is like a fish out of water. The workers directed me to a big machine with a magnet on it. Once I backed up, the operator began pulling the scrap metal out of the truck. Here’s the view looking back from the front seat:

Magnetic Metal Picker Upper

Payment

Once they had the scrap metal (as in, the non-copper metal), they weighed the truck again to determined how many pounds I had given them. I went to the office for my big payday:

copper pipe: 11 pounds at about $2.30/pound
copper wire: 39 pounds at about $0.75/pound (approximate I need to find the receipt and update this post)
scrap metal: 1000 pounds at $0.035/pound

I walked out with $85.95 cash money! Woohoo! With all my labour included, I made $6-$7/hour taking that metal out.

What the heck though - this isn’t my day job after all, and I did good: 1050 pounds of materials didn’t get landfilled, and a lot of energy was saved by recycling metal instead of mining it from scratch.

(cross posted at www.greenEdmonton.ca )

Low-carbon Solar Mass

August 10th, 2008 by Conrad in Blogs - Mill Creek Net Zero Home, Green Building Blogs, Reclaimed & Recycled Materials

I was relieved to see the the house at 9805 - 84th Avenue get torn down a couple of weeks ago. Once it was gone, I figured, I wouldn’t be obsessively compelled to recycle it anymore.

The day before the tear down, though, Peter Amerongen started talking about reusing the foundation bricks as a mass wall inside the Mill Creek NetZero Home (MCNZH). I had raised the idea a few times previously, and he hadn’t seemed all that enthusiastic, so I was going to let it go. He’s the expert at reusing old material, after all.

The night of the demolition, this is what the site looked like:

We had asked the track hoe operator to leave as many foundation bricks as possible, and he obliged:

So I took out the wheel barrow and got to work. The grey clay bricks from the foundation are in great shape. When first inspecting bricks in the home for reusability, I was disappointed because the chimney bricks were really crumbly. However, Peter has since explained that I was pulling the worst-quality bricks from the home - the bricks in the chimney (the exterior portion, anyway) are constantly being subjected to big temperature swings.

Hauling grey clay bricks by wheelbarrow.

The mass wall will be bathed in sunshine during the heating season, right behind the MCNZH’s wood burning stove. With Peter’s help, I saved 4000-5000 pounds of bricks from the old house. It’s significant because the mass in solar houses can be extremely energy intensive. Most of ours comes from concrete, which is a huge contributor to climate change.

So I feel good about these bricks. We saved diesel fuel not hauling them to the landfill, and they will act as batteries for solar and wood energy for years and years to come.

(cross posted at www.greenEdmonton.ca )

Heating System

August 7th, 2008 by Conrad in Blogs - Mill Creek Net Zero Home, Dynamic Spaces, Energy Conservation, Green Building Blogs, Renewable Energy

I’ve thought about the heating system for the Mill Creek NetZero Home (MCNZH) for months now. The home will need a very tiny amount of heat because it’s so superinsulated, super sealed, and passize solarized. The computer model that simulates the energy performance of the house (using HOT2000) has the MCNZH using 2500 kWh. That’s roughly 6% of the heat that my renovated (with new insulation and windows) 1950s bungalow uses.

So we’ll need the equivalent of 9 Gigajoules of natural gas per year for space heating. Given that being connected to the natural gas grid costs about $400/year, and 9 GJ are worth $50-$100/year, it makes no sense for us to connect to natural gas. Plus, Canadian natural gas production is waning, so I don’t want to depend on having gas in the pipe in 20-50 years from now.

So we’ll only be connected to the electricity grid. That leaves the following heating options:

1. A Seasonally-charged, Huge Solar Water Tank: This is what Peter Amerongen used for the Riverdal NetZero Project. I’ve eliminated this option. The system ends up being very complex, and I think that it loses too much heat from standby losses whilst waiting for the heating season to come around. Godo Stoyke told me that they modeled 1.5% heat loss per day, given a tank with R100 and heated to 90 degrees C. In the end, the benefit of whatever heat is left over from the summer in December, when you finally need it, doesn’t justify the complexity.

2. Ground Source Heat Pump (GSHP): I was pretty set on this option until recently.There’s a new one out that can heat your hot water too (at lower efficiency because domestic hot water needs to get quite a bit hotter than space heating hot water). It is expensive, though. Like $25,000 for a tiny system.

3. Baseboard Heaters On Each Floor And An Electric Instant Hot Water Heater. The big advantage is the heat delivery system is DEAD SIMPLE. The entire system is just so simple. Plus, although I’m not giving up on the concept of true net zero, we will have a wood stove in the home. If we burn 10-20 fires per winter (I know, I know, ground source pollutants - we’ll consider the fact that we don’t drive to be our offset for those), we will be using barely any electricity to heat with.

The question is, then, do we spend $20,000-30,000 on a GSHP that will almost never be used, or use the money to finance more solar electric, which will definitely be producing all summer long, regardless of how many fires we burn.

We’ve decided to go with the baseboard heaters.

(cross posted at www.greenEdmonton.ca )

Demolition

August 5th, 2008 by Conrad in Blogs - Mill Creek Net Zero Home, Green Building Blogs, Uncategorized

On July 30th, 2008, we demolished the 92-year-old house at 9805- 84th Avenue.

The awesome power of the trackhoe was immediately apparent, as it effortlessly tore through the front wall of the house. Given that we can dispose of such a huge (historically speaking) building in such a short time, it’s going to be a while before it becomes worth it properly recycling these buildings. Hmmm, should we spend 300 person hours and very little fuel taking this house apart, or should we spend 15 person hours and burn off 300 litres of diesel? It’s a no-brainer, really.

Not to get all political on you are anything, but that’s why a carbon tax like the one proposed by Stephane Dion is such a great thing. It would make the human labour in the above question cheaper, and the diesel fuel more expensive (okay, not in Dion’s version, but a true carbon tax would affect diesel and gas). Then, the weeks of effort that I put into saving the materials in the house would make more economic sense.

Here are some more pictures of the trackhoe doing in two hours what I couldn’t do in two months: