Last year when the architect I am working with came up with a house design based on my goals, he sent me technical plans introduced by poetic text:
The house sits like a boat riding the crest of the hill. The curved walls echo the hull. The roof is divided into three curved elements which float over the walls like three sails.
I wasn’t entirely sure what to make of this image. I liked how it described the relationship of the house to its site and highlighted the curved roofs. And a ship suggests a well-built object that uses space efficiently. On the other hand, I’m not a sailor so a maritime theme isn’t really close to my heart. I prefer a very modern aesthetic to a romantic aesthetic. I was pondering whether we could re-brand the house design as a futuristic space yacht when the metaphor ran aground.
It literally ran aground. Geological test results had came back. They showed that on one side of the house, the bedrock was 7 feet below the surface. Based on this data and on the hillside location, the structural engineer recommended sinking 25 caissons (pillars) around the entire perimeter of the house to strengthen the foundation and support the higher ceiling and new deck called for in the design.
This was bad news. When I bought the house I was gambling that I wouldn’t have to build an extensive new foundation. This was one of the reasons I had bought an existing house rather than buy an empty hillside lot. I had lost that gamble. (Well, partly, it still would have been more expensive to build a new structure). The structural integrity of the house is important to me. But the idea of spending half of my budget on pillars rather than on changes that would make the house more livable and more sustainable was depressing.
Jeremy and I met soon after we got the bad news. He described four options for proceeding.
- I could build the caissons and scale back the rest of the remodel.
- I could demolish the existing house and start over, building an entirely new structure. On the other side of the lot, the bedrock was very close to the surface, so I could rebuild on that part of the site without needing to sink pillars into the ground. One problem with this scenario was that it would be expensive to demolish the whole house. Tearing down the existing house also seemed wasteful from an environmental perspective, although some materials could be salvaged and re-used.
- I could build an addition to the existing house with the kind of architecture and green features that I wanted while making non-structural changes to the existing house. Adding space to the existing house would go against my goal of not adding square footage just because I could. We talked about putting most of the needed functions of a home into the new addition and removing the roof from part of the old house to make an outdoor courtyard.
- The same as option 3 but with a detached addition.
Jeremy then talked with city planners to get their initial reactions to these possible strategies. He discovered that if we demolished the house, building a new home would trigger a requirement by the fire department for me to pay for a new fire hydrant close to my property. The city also told him that if we built an addition attached to the existing house, we would still need to upgrade the entire foundation even if the construction was limited to the side of the property with the ‘good’ soil.
This information helped me decide to move forward with an approach that combined options 2 and 4. I would demolish part of the existing house; do a non-structural remodel of the remaining portion to improve its sustainability, interior layout, and appearance; and construct a small-detached addition where I would have more flexibility to determine the shape and materials of the building. These stages would make an already complicated hillside remodel even more complex, but I felt it would allow me to achieve my goals for the project. Plus, by combining a remodel and new construction, it would hopefully give me insight into both processes.
Next time, I’ll describe house design 2.0.
