In the process of trying to make the transition from planning to building, Andrea and I have been having some serious conversations with a local green builder, Eli, about how to turn our dream house into an actual house. I'm not going to go into too much detail about the actual conversation. I think Andrea has plans for that. But I do want to talk a bit about the thought process that followed, because I suspect this is a thought process that anyone trying to built a house might wind up going through.
During the course of planning this project, a number of people have made the same observation: that wall to the north is awfully tall. The first structural engineer that we talked to was concerned that the foundation was going to be imposing. The excavation guy had some suggestions for how to conceal it artfully. The landscape architect we consulted had some plans as well. The second structural engineer compared it to the wall of a Shogun's castle.
On Thursday, Eli got a bit stern with us about it. He pointed out that with the roof rising almost 40' above the terrain, lots of things that would otherwise be cheap get more expensive. Even putting siding on becomes a serious challenge, to say nothing of insulating the roof and putting on roofing. Furthermore, with the land sloping away to the north, having the roof rise above it means that rain will be falling off the roof on the uphill side, where it will want to run back under the house, instead of on the downhill side, where it will naturally run away from the house. Of course we want to control rain with gutters anyway, but gutters in New England live difficult lives.
The bottom line was that we were going to wind up with a house that was quite a bit over budget, without getting much for the extra money.
So with this reality check in mind, it was time to revisit our goals. Why did we want the roof to slope down to the south, rather than to the north? Why did we want to have a recessed entryway? Why did we want to have an attached meditation space? What exactly are we trying to accomplish with this house: are we really building the house we want to live in, or some other house?
When we originally set out to build this house, I had been planning to do a three-year meditation retreat in an attached retreat area inside the house. We also wanted the house to be something Andrea could be comfortable in during the retreat, and we wanted it to be a place we'd want to live after the retreat was over. We wanted it to be energy-efficient. We wanted it to be attractive outside, and pleasant, welcoming and interesting inside.
The first question is why we were attracted to the Passivhaus style of building. I grew up in Western Massachusetts. Andrea grew up in the Chicago area. So we've both lived in cold climates, and we've lived in houses that were, frankly, poorly suited to cold climates. You can build a house, enclose the walls with sheathing and siding on the outside and plaster on the inside, put in a massive furnace, and be warm all winter. You will be getting a visit from the oil company every month, and it'll be an expensive visit, but you'll be warm.
What you won't be is comfortable. Andrea and I moved from Chicago to Tucson in 2004. We had been living in a brick apartment building in Chicago's Lakeview neighborhood. It was an old tenement building, with lots of thermal mass but not much insulation, so the walls were cold in the winter. The heat would come on, the air would warm up, the heat would go off. We'd be too warm. Then over the course of ten or twenty minutes the air would cool down to the point where we were too cold. Then the heat would come on again, and the cycle would repeat.
So there was a period of about a minute out of every twenty when we were actually comfortable. Except of course that with all that heating, the air was very dry. So we were really never comfortable. We weren't freezing, and we were certainly better off than most people have been in the course of history, but we were spending a lot of money to get a pretty marginal result. I suspect that our apartment would have showed up in an infrared picture as a glowing menace, with the outside walls well above the outside air temperature.
Whether you're an environmentalist or not, it's hard to get around the fact that wasting this much heat is dumb. Energy costs money. So when we moved to Tucson, we were adamant that we'd live in an efficient house; one that didn't use more energy than necessary to stay cool in the summer, or warm in the winter. We went with a design that had a ton of thermal mass, which is a good thing in Arizona, and was insulated on the outside to keep that mass isolated from the environment.
This worked out pretty well. The house was usually pretty comfortable inside. Granted, it was dry, but that's more because Arizona is dry than because we were heating too much air. Our heating and cooling bills were quite modest, and if we turned off the air conditioning and left for a month, which we did from time to time, we'd come back to a house that was still more comfortable inside than out. So when we moved to Vermont, we didn't want to lose that.
It was the process of searching for a housing envelope that would give us the kind of thermal stability we had in Tucson that we stumbled across the Passivhaus concept. Passivhaus is efficient, but that isn't what sold me on it. What sold me on it was hearing that in a Passivhaus the temperature at the top of the room differs very little from the temperature at the floor. That the walls are not cold. That even the windows are not cold. That the thermal cycle is a few degrees, not ten degrees. That so little heating is needed that the air doesn't dry out.
But here's the thing: once we started going down the Passivhaus path, we started to think of ourselves as building a green house, rather than building a comfortable, efficient house. So despite the fact that our lot is fairly shaded, we wanted solar, because that's green. If you look at solar as a value proposition on our lot, it's not a very good value proposition. Our lot is not the best place to generate solar power.
But we were strongly attached to the roof facing south, which is necessary to generate solar power on our lot, because we had gotten into the mindset that we were trying to build a zero-energy house. And so we were about to spend a significant amount of money to create a roofline that was going to get us the solar we "wanted," and there was no way this was ever going to pay off.
The other thing that kept us focused on the south-sloping roof is the picture that used to be on the front page of the site. It's quite a handsome facade. If you turn the roof around, it's not as handsome. This matters to us. You can call me shallow if you want, but I think aesthetics matter. I want the house to look good. And we've put a lot of effort into keeping the facade the way it is in that picture, as the project has become more concrete and less abstract.
So when Eli strongly suggested we slope the roof the other way, our tendency was to resist. When he said to shorten the footprint, our tendency was to resist. And our reasons for wanting to resist are not bad reasons. But they are not central reasons. The house is going to be a comfortable, energy-efficient house whether the roof slopes north or south. We'll figure out a way to style the facade so that it looks good.
The other problem is that the house was quite long, and our lot slopes in the long direction. Because we wanted the retreat space to be available at the same time as the rest of the house, so that I could start my three-year retreat, the house length was non-negotiable. But I'm not doing a three-year retreat anymore. We don't need that space right away. I'm actually kind of interested in building a Tiny House. A tiny house would be fantastic for a month-long retreat, and there is plenty of space on our lot to site one. Heating constraints aren't as severe, because it doesn't need to be inhabited year-round.
So the tiny house plan is something that would solve our long-term retreat cottage needs in a way that I would actually prefer over the monolithic house we'd originally planned. By urging us to shorten the house, Eli forced me to revisit my motivation for building the long house, and it was immediately obvious that we didn't need to make it so long. Shortening it gives us a lot more flexibility in terms of where we place it, so that it can nestle into the terrain a bit rather than jutting out over a long drop.
It's difficult to let go of the mental freight train barreling toward the finish line that was the plan we had before we met with Eli. If we ignore his advice and build the long, south-sloping house, I think we'll be happy with the results. But we'll have a much bigger mortgage, and having a big mortgage tends to be incompatible with doing retreats. It also seems like a bad idea in these challenging economic times. If we make the changes Eli proposed, we have to let go of our emotional attachment to a few cars on that freight train. But the pieces of the house that we really intend to use—that really matter to us—we get to keep. So at this point we're pretty seriously considering taking Eli's advice.
Ordinary houses breathe through leaky joints and poor seals, losing heat and wasting energy. But our house won't leak, so we'll use a heat recovery ventilator (HRV) to admit fresh air and expel stale air, transferring heat from one stream to the other.