Auerhaus Home Page

Ecology

There is a lot to consider in trying to be greener. Here's a list of ecologically sound and not so sound things I did.

>Site
The site was chosen to be south-facing, and on already disturbed ground. As it happens a pretty nice view too.

 

>Size
I've been amused at how big some not-so-big houses are. The average US home has grown from 1800 sq. ft to 2400 sq.ft since 1975 (NAHB). This in spite of a drop in average family size. I think some of this is a consequence of the 90s boom. People started to think of their home as a product built not just for themselves, but for future buyers. Thus the building of more space than is needed now in anticipation of what might be more saleable in the future. I personally think this is misguided. There also seems to be a building in of dedicated separate spaces for activities that might have been in shared spaces or outside the home. Gyms, home theaters, sewing rooms, etc.

I wanted more of a cabin feel, and I was inspired and informed by the book The Cabin by Dale Mulfinger and Susan E. Davis. Even so, I ended up building more than the 800 square feet I'd originally intended. Most of it is the unintended 800 sq. ft. basement accessible from the outside only. This happened because the slope of the land necessitated a 5-1/2 foot tall crawl space, so I went ahead and poured the other two feet. The basement slab floor ended up being a last minute engineering requirement. I also plan a 70 sq. ft. loft just because it will make a nice office space. The porch adds about 600 square feet.

Less size means less of most everything. Less energy, less material, less land area, less upkeep.

>Layout

The house uses an old idea of locating all the plumbing back-to-back. This reduces the amount of plumbing pipe, reduces space and complexity and means hot water runs a shorter distance to the tap, conserving water. This is aided by locating a small (20 gallon) marine hot water heater directly overhead of its point of use.

The house minimizes northern exposure by putting no windows or doors there and making it only 7-feet high. I learned early on, in Oregon the north side is only good for growing moss.

I used Dan Chiras's The Solar House as a guide to determine the optimal window area. His book is an excellent resource, and kept me from accidentally building a greenhouse.

>Foundation
There are very few good options for a foundation other than concrete especially in this wet climate. Concrete uses a lot of energy to manufacture, a process which releases mercury into the atmosphere. It also takes a lot of energy to transport. Yet it is still one of the least expensive materials per square foot.

Use of fly-ash, an industrial waste product, is a way to offset some of the negatives of concrete. I wanted to use 25% fly-ash, but could only get 15% in the footings, 10% in the walls and none in the floor. Along the way I was told fly-ash would make the concrete weaker (it makes it stronger) and that it costs more (it costs only a fraction of the concrete it replaces).

Waterproofing of the foundation is an oft overlooked area where a good substitute for petroleum-based products is available. I used a bentonite clay mat . It was ironic that it was mined in Canada, sold by a Texas company and shipped and installed in the clay-rich soils of Oregon. Bentonite is so benign it is sold in health food stores.

>Energy Conservation
Use of SIPs (structural insulated panels) is possibly the most significant conservation element of the house for these reasons:

  • Superior insulation - Not only are the ratings high (6" walls R30, 10" floor and ceiling R40), but the actual performance is high. This because of the high fit and quality of in-factory construction and no studs (i.e. more foam and fewer conduction through nails.
  • Reduced material - The foam itself is quite rigid and is pressure sandwiched between panels of OSB. The result is a panel without need for studs. Even my floor of 10" thick foam needed only double 2x10s every 4 feet to support a 13-foot span. The even longer ceiling has only decorative rafters. In my case I simply painted the OSB on the inside rather than sheetrock, saving more material and effort.
  • Reduced waste - According to the EPA new residential construction generates about 4.5 lbs/sq. ft. in waste. Over 6 million tons per year (136 million tons for all construction). With SIPs, one's house is cut out of 8-foot by 24-foot panels in a factory where material use can be minimized across projects. On-site there is no waste from the building envelope.

I heat my house on 1 to 2 cords of wood a year, about 27-million BTU Most people around here use 6 to 8 cords. At $16/Mcf of natural gas this is the equivalent of an annual fuel bill of $390. That's a year, not a month!

I purchased my panels from Energreen, now Insulspan.

>Reclaimed Lumber

An old barn and shop on the property were turned into solid fir flooring, cedar siding and the better part of the electrical and water sheds. All the doors were made by Mountain View Door & Window from gnarly, wormy wood.

The posts for the timberframe came out of the old Cottage Grove High School. Other parts from an old Safeway.

>Recycled Material

The kitchen and bath sinks were found under debris in the shop. The cast iron tub from the ReBuilding Center . The bathroom lamps from Hippo Hardware & Trading Company. The mirror frame is a discarded window found in the woods.

The barn's aluminum roofing was reused on the porch roof. It has old nail holes in it, but doesn't leak as the holes are on the ridges. The holes allow little shafts of sunlight through.

>Local Materials
I was amused to read a recent article about a couple who moved to a small mountain town in Denver and built an "environmentally friendly" house. The owner was aghast at the difference in price between regular and sustainable mahogany. Last time I checked (just a moment ago), oak, fir, and pine are native to Colorado. To be fair, my floor tile came from Italy, but it is one of the few materials not made in the northwest.

Naturally wood is easy to come by in Oregon, so wood is a good choice. Because of the use of SIPs there is a lot less lumber in the house. I didn't bother to get FSC certified lumber mostly because of the effort involved. At the time, 2004, FSC lumber wasn't a stocked item. The cedar for the deck was all locally milled and even graded right on site.

>Alternatives to toxics
It is my view that by trying to make things last longer and be maintenance free we are only succeeding in making our trash last longer. One thing i tried to reduce was the use of toxics to keep wood from rotting or even fading ("discoloring"). The cedar that came off the barn was an inch or more thick and looked great after a half century. The empirical rate of wood erosion is only about a millimeter per decade or less than a half inch a century. I figure my house will need new siding in about 150 years or so. Until then it will never need painting, staining or any other form of maintenance.

The deck may need some work sooner. Maybe in 50 years.

I did have to use 10-gallons of sealer on the plywood used in the soffit.

I chose all wood windows from Sierra Pacific (instead of vinyl, vinyl clad, painted or metal clad) for their appearance, but also to use fewer toxics and because they would ultimately be biodegradable if nothing else. SP has local offices, had the low bid and were one of the few that would sell an unclad, unprimed window (although they came without a warranty). I did end up sealing the outside with Daly's sealer.

Interior finishes are: Behr paint, linseed oil, mineral oil and some tung oil.

By not using toxic sealers I was able to burn all the scrap material for heat and cooking.

Instead of copper I used PEX tubing for hot and cold water.

>Rainwater Catchment
Auerhaus is the first approved rainwater system in Clatsop County. All the water I use comes off the roof. I was planning a rainwater system, but I was forced to make it a primary source after drilling 227 feet and finding only a gallon a minute of blue mud. I was naive. I thought if you moved to the country, you dug a well. And in Oregon how could there not be water? When my well came up dry locals asked, "who witched it?" When I replied, "I'm a man of science, I don't believe in witching or dowsing for water," they just shook their heads in sad disbelief. My neighbor Hank even loaned me his copper rods that had found water on his property. And I had to admit I did feel them cross and not where we drilled.

Read more about the system here.

>Grid-tie Solar System
Auerhaus is the first grid-tied solar house on the West Oregon Electric Co-op system. It's just me and Bonneville Power. My system is small. 1500 watts of panels, a 3600 watt inverter and 400 amp-hours worth of batteries. My electrical bill is about $45/month so my bill will not be zero. I figure I would need 3-times as many panels to get to net-zero. Maybe in 20 years, the life of the panels, I'll be able to replace them with panels that are 3-times as efficient in the same space.

The best thing has been the battery backup. We are subject to frequent outages in winter. It is comforting to have some lights, outlets and the fridge remain on during a storm. And it is essential that my UV water purifying equipment stay on. I have about 36-hours of backup power if there is little or no sun to recharge the batteries.

Read more about the system here.

 

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