How Does Building Geometry Affect Energy Performance, Aesthetics, and Construction Cost?
Creating a great modern home is a balancing act of seemingly endless choices. Every design decision influences your home, but not all decisions are conducive to creating a great home. Architects are master problem solvers; we consider how the geometry of a building can affect its energy performance, aesthetics, and construction costs.
In this article, we will explore the basics of how building geometry impacts these three important factors. By understanding this, we can create great modern homes that look great, are energy-efficient, but not exorbitant when it comes to the cost.
Energy Performance
It is important to understand how our homes use energy to better recognize how the form can help, or hinder, energy performance. The average home uses nearly half of its energy consumption on space heating. The primary contributor to this is the building envelope. This doesn’t mean we need to get rid of windows, but rather place them in the correct location to take advantage of the sun.
A more compact form does well to maximize energy performance because it reduces the amount of exterior surface area. This means there is less surface area to lose heat (or in the summer, gain heat). A simpler form results in fewer corners which reduce the amount of air leakage which allows heat to be transferred in or out and never in the direction you want.
We can use energy modeling to assist in the design process to understand if we need to increase or decrease the number of windows; extend the roof overhang to block sunlight; thicken the wall to reduce heat loss/gain. A great modern home should look great but it should also have great energy performance.
Energy modeling tools are great because they allow quick iterations and checks for assumptions. Understanding the basics is important but being able to fine-tune how a (or many) window adjustment(s) affects the overall energy usage would be cumbersome to determine with a pencil and paper. Remember, a great modern home should look great, but it should also have great energy performance. Let’s jump over to the topic of aesthetics!
Aesthetics
We all care about aesthetics so why wasn’t this first? Although we find them to be objective, some find aesthetics to be subjective. We won’t deep dive on this topic but rather hit on some knowns: a simpler form is more beautiful than a busy form. A human-scaled proportion will be more desirable than a sprawling cavern. We desire connections to light and nature so a windowless box doesn’t pass for good aesthetics. We should be thoughtful in design to consider all of these.
Architectural elements such as shape, proportion, and scale contribute to the aesthetics of a home – these are all characteristics of the building geometry. The shape of a house defines its character and sets the tone for its overall visual appeal, with different configurations evoking varied responses. Proportion, referring to the relationship between the sizes of different parts of a house, is key to achieving a harmonious and balanced design. It dictates how well the elements of a house fit together and contribute to a unified aesthetic. Scale, on the other hand, connects the size of architectural elements to human dimensions, ensuring comfort and usability. These elements combined, when thoughtfully executed, contribute to a visually appealing and comfortable home.
Construction Cost
We all have a budget, so this is important – for some this might be the most important. Every move we make will influence the overall construction cost. We know that generally the simpler the form, the easier it is to construct. A complex form, therefore, is more difficult to construct, thus increasing the cost. There are exceptions to the rule but for our purposes of designing and building a great home, we’ll operate with this as the rule.
Other elements and design moves that affect construction cost are corners and windows. Remember our point about the simple form from above. As we add corners, we add cost. The same is true for glazing – windows. Windows and glass are more costly than a regular wall – even brick. As we increase the amount of glass, we increase the cost. The ‘hidden’ cost of windows is energy usage. Windows have a disproportionate effect on the energy efficiency of your home, consequently, we need to add additional insulation to account for this increase in glazing, and decrease in thermal performance. This can turn into a run-away cost train if you’re chasing energy efficiency.
Some pro-tips: Fixed glazing, or non-operable windows, cost less than operable windows. We also know that insulated glass generally performs better than window frames so larger expanse of glazing are better (performance wise) than a bunch of smaller windows. Finally, we know that in the northern hemisphere, windows on the north side of the house do not contribute to heat gain, only heat loss in the colder months. This can be a sizable liability when it comes to keeping the house warm.
One must keep in mind that one needs to operate the house, so the up-front cost isn’t the only cost. Each month the utility bill arrives unless you’re off the grid – in which case, you’re going to pay more up front for additional solar panels to generate enough electricity to cover the need. See where this is heading? There is a fine line which needs to be walked in order to create a great home.
A more compact home will cost less to build, AND cost less to operate (heat, cool, etc). The larger, more sprawling a house becomes, the more costly it will be to build but also to insulate. The more energy a house uses, the more solar panels are needed to offset the energy need, resulting in a higher construction cost. Conversely, the lower the energy need, the easier and less expensive it will be to offset that need with solar panels.
There is a lot of thought and consideration that needs to be given to create a great home. At HAUS, we understand how the geometry of a building affects Energy Performance, Aesthetics, and Construction Cost.
HAUS is uniquely positioned to help lead you on the journey of building a great home because not only do we have years of experience and learning – but we are also ‘in the trenches’, managing the construction of our projects. We bring expertise to the table from both the theoretical and physical sides.
