3. Design

Design covers a wide range of topics. On the one hand, it’s simply the planning stage of a construction project. On the other hand, it’s where all of the critical decisions are made, including how the house will look and be experienced by its occupants and visitors. Some of the key elements to consider regarding design:

Location. Is the house in the city or the countryside? Packed in tightly with its neighbors or on enough land to be a farm? Are shops, jobs and services available nearby, or do they require travel? Are public transportation or bicycling options, or does any travel require a vehicle? These are some of the many issues regarding location.

Size. When we developed the Pretty Good House guidelines, we came up with the following targets for building size: 1000 sq. ft. for one occupant; 1500 sq. ft. for two occupants; 1750 sq. ft. for three occupants, and 1875 sq. ft. for four or more occupants. The national average is much higher, and many people find it easy to live in smaller spaces. The important thing is to deeply consider how much space you really need, consider flexible spaces and clever storage solutions to reduce the amount of space needed, and get rid of stuff you don’t need. House size relates directly to resource use and cost, so the smaller the better.

Orientation. The ideal house, from an energy point of view, in cold climates, will face south, with some windows (but not too many) on the east and west, and few or no windows or doors on the north. There will be a south-facing roof to support photovoltaic panel installation. But every site is different, and compromises need to be made. Fortunately, windows, doors and solar panels keep getting better. But it’s still best to keep the house oriented within 30 degrees of south, if possible.

Shape and complexity. The larger the surface area of exterior walls and roof is for a given floor area, the less efficient the building is to build and heat (or cool). The most efficient surface-to-area shape is a sphere, but that’s not practical to build. (Sorry, Buckminster Fuller.) The next most efficient shape is a cube, so boxy two-story homes are common for high-performance homes. Single-story homes, especially ones with a lot of corners, will generally cost more to build and will use more energy than a comparable two-story home. Complicated rooflines are also more expensive than simple roofs and more difficult to insulate well. Complicated rooflines are also more prone to leaking over time and may provide less area for roof-mounted PV arrays.

Beauty is in the eye of the beholder, but for a house to be loved by more than its owner it should follow societal rules for what makes an attractive house. You may choose to follow historical styles, contemporary styles or a blend of the two.

Comfort and performance. These two are closely linked; a big part of what makes a high-performance house high-performance is that it’s comfortable to live in. The building envelope should be air sealed and insulated well enough that an occupant does not feel too hot or too cold or feel drafts. A well sealed and insulated building envelope requires a smaller and more affordable affordable heating system.

Integration of trades. In conventional homes, the various tradespeople that come through during construction do what they need to do, usually without a lot of thought to how it will affect other trades. A better approach is to plan ahead so everyone knows what to expect and so there are no conflicts. A good general contractor (and the design professionals) should be familiar enough with all trades that they can direct traffic in the right direction. This is often a downside to owner-built homes; although it’s possible to build a very good house without a lot of experience, there is a lot to know and to anticipate, and it can be helpful to have a GC on board who has been around the block a few times, preferably with other high-performance homes.