Follow my progress as I build the first-ever net-zero home in Spring Green, Wisconsin and I’ll keep you up-to-date and send you Open House invites!
November 1: My plan calls for a slab-on-stem-wall home, not a framed-floor-on-basement home. It’s an unusual choice for our corner of the Midwest, and a little risky from a re-sale point of view. From a low-carbon-footprint and affordability point of view, it makes perfect sense.
Concrete is a high embodied energy material. That means a lot of energy has to be expended to quarry the materials, transport them, crush & cook them, and deliver the mix to the building site. The less concrete used, the better for the environment.
My stem wall is 4′ high, so compared to a basement with an 8′ ceiling, it uses half the amount of concrete. I considered a few alternatives: Insulated Concrete Forms (ICF) or Durisol block—both of which use less concrete, and a Frost Protected Shallow Foundation (FPSF) which uses even less. These alternatives aren’t exotic, but require some amount of special order and special expertise. One of my goals for POEMHOMES is to make choices that are easily replicated. For my first go at general contracting, I need things to be somewhat “plug & play”. A 4′ stem wall is familiar to the trades—and manageable by me.
Having no basement saves money because there’s no stairway and no framed floor. There’s no need for drain tile, damp proofing, and a sump pump (with backup power). Potential leaks or flooding are eliminated—-and so too worries about mold and mildew. An insulated slab stays high and dry and the hard trowel finish becomes the finish floor. When the sun shines, it soaks up heat energy—releasing it back into the rooms as temperatures cool. A slab can be set on or close to ground level, for easy accessibility. I’ll have one 8” step up—not the usual 20” or more necessary in conventionally framed floors.
Of course there are disadvantages and trade-offs. With a basement, mechanicals are easy to install and switch out. Storage is plentiful, you can build out a rec room or additional bedroom, and you’ve more-or-less got a tornado shelter. A slab commits you to a smaller footprint (sans future addition). You have to find space for a mechanical room and plan ahead for plumbing, electrical, and HVAC runs.
My design has a small walk-in-closet on the main floor for the grinder pump, water softener, and hot water heater. Above is an attic of sorts, for the HRV (heat recovery ventilator) and the ASHP (air source heat pump). Electrical runs and ductwork will be routed across the length of the house above the living areas.
Notice in the illustration above how the slab rests on a 4″ layer of foam (blue), which overlays sand fill (brown). It’s a lot of fill. The lot looks flat, but it’s not.
A tornado shelter—if done to FEMA standards—is a major expense. I’ve wrestled with this, and am satisfied I have a good-enough answer. See future posts for more.
Slabs may not be most people’s preference, but if the Village of Spring Green is going to grow they are inevitable. People here remember the “Flood of ’08”. Rising groundwater—from record-breaking rain the previous summer, record-breaking snowfall that winter, and above-average rain that spring—flooded basements and sent homeowners packing. A whole subdivision—-just a mile north of me—was razed. To forestall more financial ruin, the Village passed an ordinance—affecting lots just a stone’s throw from mine—that restrict basements to storage and utility only—-no “below grade living space”. Other lots require slabs. My goal is to show how liveable, pleasant, and affordable a slab home can be.
October: It’s been a month of slow—but steady—progress at the site, as contractors schedules back up due to heavy rain and end-of-season demand. I keep in touch, trying to entice them to my dry “beach” lot. Up in the surrounding hills, soils are heavy, rocky, clayey, and saturated.
Neighbor Lew Lama of Wood & Stone Works from Spring Green helped me stake the house perimeter and highlight the outline with spray paint. Slaney Excavation dug for footings.
Next, footing forms were set, poured, and stripped by Matteson Concrete from Spring Green. Next, wall forms were set, poured, and stripped A boom truck had to be called in from Reedsburg to reach all the way around my unusual turned-90 degrees-to-the-street design. The wall pour took a mere hour.
The Concrete Remover came from Madison with his special curb-cutting rig. I’d never seen that done and it was pretty cool.
Good friend Mark Morgan from Bear Paw Design & Construction came down from Eau Claire to help me improve the look of the concrete walls where they show above grade. Usually, this area is left as-is—-leaving not-very-attractive ridges every 2 feet where a form panel butted the next. He took on the hard work of power grinding while I knocked off form ties and patched them with a cementitious product that will prevent the embedded steel from rusting out.
Temporary electric was installed by good friend Bob of Rowen Electric from Dodgeville. I helped him wire up the box in the shop and install the post on site. It took real effort to pound down two 6′ long steel grounding rods—once again I was grateful for my sand.
Things get messed up, but also utility flags expire so Diggers Hotline had to be called back before Slaney Excavating could start to move dirt. It will take 3-4 days to lay base for the driveway, fill in foundations, compact for slabs, and complete rough grading.
September 22: The Village of Spring Green is built on an ancient deposition of sand. My lot, at the edge of town, was still farmed in a rotation of alfalfa, oats, and winter wheat. Irrigation rigs and regular infusions of chemical fertilizers made it worth it—-but under my watch, that will change.
I’m concerned about chemical blow-back and dust from farm operations and a little distressed about distant traffic noise. A dense, mixed planting of deciduous and evergreen trees and bushes along the west border will help—and keep cold winds at bay. The rustle of leaves will help mask highway drone. A small earth berm would add sound-deadening mass, and create a sense of enclosure while blocking and filtering soil runoff. Here’s how it could work:
What is home without a large vegetable garden? The topsoil Slaney scraped off was a thin layer, only about 6-8” deep. A scoop shaken with water and left to settle is an easy and accurate-enough way to test its composition. Google “Mason Jar Test”.
Measured, my soil is: 72% sand, 28% silt, with no discernible layer of clay
Ideal garden soil is: 40% sand, 40% silt, 20% clay
Classified, my soil is “Silty Sand” or “Loamy Sand”. It drains quickly (good for foundations), but can’t hold onto moisture or nutrients. For my garden to thrive, I’ll need to add clay and organic matter, with a top dressing of mulch to retain moisture.
Soil erosion is a real problem on most construction sites, and Wisconsin’s Uniform Dwelling Code is pretty strict about what you have to do to control the perimeter. My lots flattish terrain and the sandy soils ability to absorb water quickly means erosion or runoff (sheeting), shouldn’t be a problem—even in a heavy rain event. But protocols must be followed. Options include landscape fabric silt fence (most common), straw wattles (what Slaney recommended), or straw bales—which is what I chose. I agonized, because bales are by far more expensive—and heavy to handle. But I just couldn’t bring myself to buy a bunch of plastic, only to throw the muddy mess away after final grading and established ground covers stabilize the soil. Minimizing landfill waste is a key goal of POEMHOMES.
Straw wattles are better, with only a light weave of plastic containing the sausage-like things. But straw bales come clean (well, there is plastic baling twine). I could get them delivered from a local farmer and can use them later for mulch. With help from my son and his girlfriend, we worked our way around 300 bales—pounding two 2×2 stakes into each one. Spring oats, tossed on the piled up topsoil, should hold it together until next summer.
Later—my attention now keenly attuned to soil erosion—I noticed several very bad silt fence installations. Here’s one that’s been breached. I’m pleased to report that my bales have stayed intact, and there’s no apparent erosion.
August 14: I spent a few hours with shovel and tape measure intent on finding my property corners. The subdivision was platted only 13 years ago, so I was reasonably confident the steel stakes set at that time would still be intact. If successful, I would save myself the $200 a surveyor quoted me to come out and set flags. After overturning more than a few humps of sod, I found all four about 6” below grade. Later, my crew and I will pound wood stakes alongside and run string lines between them to measure off the house perimeter.
September 7: Finally, my building permit is in hand and we are a GO! After many months of drawing, revising, researching, and selecting materials & subcontractors I was ready for plan review. I cracked open my still fresh-smelling vinyl checkbook and cut my first POEMHOME check.
As a professional designer (with an Associate’s degree in drafting), I’ve prepared construction plans for over 120 new homes. Many people are surprised to learn that in Wisconsin—as in many states—residential projects don’t require an architect’s stamp. In fact, anyone can design a new home. Plans have to pass muster, and each stage of construction has to pass inspection—but it’s all within reach of a conscientious person.
A homeowner can pull a permit and build their own house—as long as they subcontract out the mechanical trades to licensed professionals. Anyone who’s building a home for someone else needs to be registered with the State. Even though I’m building this house for myself, I took the “Dwelling Contractor Certification” test and am now a licensed residential contractor in Wisconsin. With any luck, this won’t be the last house I get to build.
September 21: My birthday present this year was a visit from my sister and her smarts to set up this POEMHOMES website. That was back in June, when I was still drawing. She asked me what the latest date was that I could start construction and still beat winter. Overwhelmed, I guessed September 20th.
I was momentarily furious (in a how-dare-you, why-didn’t-you-even-ask-me kind of way), when I later discovered she installed a little calendar app on this website that flipped down to my so-called groundbreaking. I now take it all back, and am thankful for the sisterly nudge. We did indeed begin today, just one day off.
Slaney Landscape & Excavating of Dodgeville texted me this morning that he had clearance to dig. A few days before, he’d called Diggers Hotline to have the site flagged for utilities. He scraped the lot clean of topsoil and placed it in neat mounds on the south edge of the lot. What was left was a wonder to behold—a beach of the finest and softest sand imaginable!
August 1: I feel drawn to particular landscapes and sometimes, man-made places. When that heart-tug comes over me—whether it’s nostalgia, familiarity, or something more mysterious—I know I’m connected to the Earth and I’m alive in the moment. I treasure this feeling.
One such place that draws me is the Spring Green Preserve. So it’s no small thing that from particular vantage points (and by craning my neck), I can see this promontory from my lot. When climbed, this dry sand prairie bluff offers commanding views up and down the Wisconsin River and buzzes with unusual flora and fauna.
Another place is the Wisconsin River, just a mile away—a seemingly endless stretch of sandbars, eagles, herons, and the hush of solitude. Wild edges await at Bakkens Pond—and further west, Smith Slough & Sand Prairie. I often imagine myself back in time, when these paths were lightly trod. Who lived here, how did they make provisions, what did they see and hear?
So you can imagine my delight when I found the original surveyor’s map of the region, platted in 1840 by Wm. A. Burt. He transcribed the contours of the river edge and islands big and small and edged them in blue. My lot sits in the SE ¼ of the NE ¼ of Section 12 at the edge of what was once a 6 mile stretch of a “B. Oak & Pine Grove”. Remnants of this grove can still be seen along the highway just east of Lone Rock.
Note to self: plant a Burr Oak and a White Pine.
June 20: After 30 years of living in the country, I began to think about moving to town. Like many people nearing retirement, I was looking for a way to simplify my life and reduce the daily chores and maintenance demands of owning a large house and grounds. Putting down new roots in a friendly place where I could walk to the library and meet people at the coffee shop sounded good. For me, that friendly place is Spring Green, Wisconsin.
My heart was set on a contemporary, net-zero house—a house that didn’t yet exist. Finding a suitable lot took several years and an evolution in thinking. I envisioned my smallish, modest home tucked along a tree-lined street, in an older neighborhood close to the activity downtown. It would be similar in size to nearby houses, with their quirky arrangement of old garages and tool-sheds that created private little backyards and cozy gardens. Out front—a sidewalk, with people passing by.
One lot slipped through my fingers because I wavered. Another lot befell a similar, more complicated fate. I kept biking around and around the neighborhoods, looking for some “lost” parcel. The only listings were on the fringes, out in the bleak and bland subdivisions. Or so they looked to me.
One day I stopped and had a good look around. Big, boxy homes, check. Vinyl siding and faux stone, check. Overly large lots with no trees, check. Wide streets and large front-facing garages, check. No sidewalks, check.
But then there was one. Maybe I could make it work. It was a 20 minute walk from the coffee shop. Nearby woods and an open field beyond made it feel like country. No trees on the lot meant more solar heat gain and sunshine for a vegetable garden. I could plant a windbreak along the west edge. If I turned the house 90 degrees, I gained some privacy while still putting on a neighborly face.
Like many subdivisions, there were covenants. There were two that rubbed the wrong way. The developer required that any plan include an attached two-car garage and that any one-story house be at least 1500 square feet. My plan was only 1000 square feet, with a semi-attached one-car garage.
I noticed that around the corner was row of smaller-looking houses on smaller-looking lots. I found out the size restriction for those lots was just 1200 square feet. So in my offer to purchase, I included a drawing showing a 1200 square foot house with a semi-attached two car-garage, facing away from the street. My Realtor later said she’d expected some pushback.
Here’s a preliminary plan of how I’ll arrange the house on the lot, and how I’ll use landscape to enhance energy-efficiency. A mixed, densely planted windbreak (ideally planted on a low berm), protects the house from winter winds and driving rains bearing down from the northwest. A retaining wall surrounds the vegetable garden and raises it up to the level of the house for easy access. The rest of the yard follows natural grade, directing storm-water runoff to a rain garden where it can slowly recharge the aquifer. Out front, prairie grasses make way for no-mow or low-mow grass in a nod to suburbia. Deciduous shade trees placed along the east and west provide cooling breezes without blocking sunshine to the large windows facing south and the PV array on the south roof. If possible, I’ll lay pavers or pour a permeable driveway instead of the concrete driveway required under the covenants. Permeable concrete is made from gravel and cement only—the sand component of conventional concrete is eliminated—so that rainwater flows into the surface instead of sheeting off the surface. In this way, the aquifer is recharged and pollutants from car oil, etc have a chance to decompose instead of polluting surface water.
While my smallish, contemporary house might look like a duck out of water next to it’s more conventional neighbors, my hope is that it also looks like it makes sense. My plan is to break ground in September 2018, or if that’s rushing it, then May 2019. I hope you’ll continue to follow my progress!