Landscaping

Thirty years ago we landscaped our yard. When landscaping around the house, I attempted to follow the best practices to enhance energy efficiency for the house. Our house is not properly situated on either a north to south, or east to west axis.  Instead the front of the house faces northeast, and the back southwest. Normally, this orientation would not pose much of an issue, but when I examined doing solar panels, I found an issue.

Aerial view of my house showing tree cover of most of the
southwest roof. The pin (teardrop) is on the peak of the roof
Source:  Google Images

While landscaping, I tried to make the best of this orientation. For example, I know that the strongest winds are generally from the west and northwest, and hence the side of the house that faces the northwest (about 323 degrees) I planted  arborvitaes which act as a windbreak, they also screen the house next door. I placed an evergreen tree to the northeast corner of the house to also help block wind. To limit sun gain in the summer time I planted shade trees in the back yard near the house. The back side of the house faces southwest (about 233 degrees).  The trees to the direct southwest of the house which I planted are locust trees which have a smaller leaf, but a large canopy with both able to extend about half way over the house roof.  I last had the trees trimmed in June 2020, to better form and keep branches from hitting the roof or the house edge. Having them trimmed is rather expensive.  However, the trees provide value in shade which provides comfort to people and reduces cooling costs of the house, lessens area of lawn that is fully exposed to the sun, and hence the grass stays more green in times of drought and/or hot temperatures. The downside is that many of the nice flowers for garden beds like more sun than shade, so it is a balancing act.  The canopies are sufficiently large so that, as the trees have grown, half of my rose and flower bed is mostly shaded, which has taken down the quality of the flower blooms.  Or, as in some cases, the sun loving plants just gradually fade away.

Two Locust Trees along back of House

Due to house orientation the front lawn does not get much sun.  The lawn is shaded by the house, a large ash tree in the front yard, and a street tree that is a locust tree. The street tree was not in place when we moved in the house, and was planted a few years after we bought the structure. I would have thought the realtor would have mentioned it, or they would have had something in their deed restrictions (like I required of developers in Fitchburg when we started to require street trees).  Hence, I have two shade trees in the front of the house rather than my anticipated one shade tree in the front of the house. The area of the front lawn closest to the house does not get much sun, and the lack of grass shows this to be true.  It also shows how trees break up the rain fall, as this part of the lawn seems dryer, even though it is shadier.  

My thoughts on how I landscaped to reduce climatic effects on the house--lower cooling and heating costs, came to mind when I was examining, a couple weeks ago, the possible placement of solar panels on the house. This is where the house orientation poses a problem. The roof on which the panels are best placed, unless a ground mount is used, is best south and then oriented within 90 degrees of south. If south is at 180 degrees, that means it should range from 90 degrees (which is east) to 270 degrees, which is west. My roof line is oriented with the long alignment of the house, which means I have one good roof location for solar, and that is the southwest roof which gets shade from the trees I planted thirty years ago. I really do not want to cut down the trees, nor is it likely financially feasible to place the panels on my northeast facing roof, as the solar efficiency factor is just not  present. 

Northwest edge of the house and arborvitaes
planted to reduce wind to the house. 

My last several years as a planner, as photovoltaic was becoming more affordable, I attempted to get subdividers to position the main lengths of streets east to west so that homes would have much of the roof face south or north. This was based on the fact that many homes have their roof line run with the main axis of the house, and the main axis is often along the street frontage, although it does not need be that way. However, given the 90 degree ability from true south an orientation north to south may be better as you would have, if the house roof ridge ran that direction, two roof faces for solar.  If my house was at a north to south orientation, I would be able to place solar panels on my east roof, say above the garage which does not get much shade at all.  As it is, I am limited to a roof that has the most shade from my passive energy designed landscaping.

Evergreen landscaping planted in the
northwest corner of the yard.

This of course, raises the issue of what passive use of landscaping verse keeping solar. Without shade, a house will get much warmer leading to more cooling costs.  The house in which I grew up, which my Dad designed, had a larger overhang to the south, such that the heat of the sun was blocked from the south windows from, say mid-spring to mid-fall, but was able to get in  the south rooms during the other times of the year to reduce heat cost. House builders have gotten away from such simple measures to reduce the sun affect on a house. Instead of simple design techniques you have energy efficiency requirements which depend on insulation and windows and door openings. By requiring such overhangs, would probably limit the creativity of architects or designers, although that does not mean such passive techniques cannot be used.

Of course, rooftop solar poses an issue too. If a house lacks shade, you may get energy from the sun, but you are also likely paying more to cool the house due to the energy gain from the sun. Not to mention days when you may not need cooling due to the trees, but would need cooling if the trees were not present. In addition, landscaping, trees, shrubs and flowers all provide a non-tangible benefits to the human mind, body and soul.  It is all a balance.

As to the orientation of our house, for me, it means if I wish to go solar I will likely have to explore other options than panels on the roof.  Given the size panels required to offset our electric usage, which by the way is low for other comparable houses, I doubt I wish to see that size freestanding in my yard. After all, I still need a place to play football, even though my body, and my wife, will tell me not to. I do, however, take comfort in the way I landscaped the yard to obtain benefits to the house, ourselves, and our energy bills.