Could a single-family home ever be more eco-friendly than a small apartment?

For almost two decades I lived in a variety of small urban apartments in multi-story buildings. Those buildings are pretty efficient in terms of heating and cooling; most units have only one exterior wall. Plus, having less than 500 square feet per person (in some cases, a lot less) means less energy expenditure than heating or cooling (and lighting) a whole 1300 sqare foot home for 2 people, which is what my husband and I have now. Not to mention the relatively small amount of shared outdoor space in an apartment complex versus thirsty individual lawns. (For purposes of this discussion, let’s leave cars vs. public transit out of the calculations, though obviously that’s significant.)

I knew this was a selfish choice, but we’re trying to mitigate our footprint as much as possible. We have a front lawn, but we’re not watering it at this time. We’re only watering the succulents and the trees, and a lot of the water we’re using for that is recycled–I wash my scuba gear and then dump it out on the plants instead of pouring it down the drain, as I did when living in an apartment. We’re thinking of putting in kurapia or another drought-tolerant ground cover instead of grass. We started composting, which has cut our trash output significantly, and we’re growing a tiny bit of food in the backyard. We also have ambitions of putting in solar panels, maybe a gray water reclamation system, perhaps a heat pump and/or some better insulation.

I realize the answer, at least for us, is probably going to be “no”–we’re never going to be living as lightly on the earth in this house as we did in our old apartments. But theoretically, is it possible? Is there enough technology out there to make a house as green as a typical apartment? I realize the answer is also complicated as it requires weighing the impact of different kinds of environmental harm, but that’s always a challenge in these discussions, so I’m hoping there’s at least a framework for analyzing it, if not a definitive answer we can all agree on.

Yes, I think it is possible for some single-family homes (SFH) to be more eco-friendly than some small apartments.

The smaller and more energy-efficient the SFH the more likely this is to be true. Really good modern insulation and careful construction can substantially increase the energy efficiency of a home.

As a reverse-example - the apartment I live in is small, but it is poorly insulated (dating from when energy was cheap) so it is expensive to heat even if it is a small space, and the roof retains heat in the summer and re-radiates it to the top floor apartments, requiring more energy to cool. Due to the height of the water table and depth of the basement there are energy requirements to keep the basement dry. The toilets are old-style and use more water than newer toilets. Likewise, the furnaces and waterheaters (individual to each apartment) are also older and less efficient than newer models. The landscaping is mowed with gas mowers and chemicals are used by the management.

A small SFH with really good insulation, modern appliances properly sized to home/occupants, with landscaping leaning towards native plantings and tended by hand tools could in fact be more eco-friendly than my current small apartment. Add in some composting and a garden, use of greywater for irrigation (such as you do), and sure, it’s possible.

Is it likely? Um… probably not.

Solar panels may or may not be more eco-friendly. Certainly while in use they are, but they aren’t necessarily eco-friendly to produce or dispose of once their useful life is over (they don’t last forever).

Try putting in a green roof.

Add in once-weekly showering and a thermostat set to 60 in winter and 80 in summer and voila, guilt-mitigated living.

The cars vs public transit vs walking part is a big one to ignore, because it has such wide-ranging effects. It’s not only about how you get to work and the store, or how the kids get to school, but also how much piping, wiring, pavement, stormwater retention, and other services and utilities exists to serve your home/apartment, which extends beyond just your immediate street frontage. Any single-family home is going to have more of those per-unit than an apartment. The Prius or Tesla in the front driveway still spawns multiple parking spaces throughout the city that create their own problems.

One advantage that the single-family home has is that you have more ability to install various improvements. If you want better insulation or multi-pane windows or solar panels on the roof or whatever, you can just get it. With an apartment, though, you’d have to convince the landlord that it’s worth their while.

I think to some extent, you can’t think in generalities such as “a single family house vs a small apartment”. For example, I live in a single family house. It might be 1200 square feet if you include the unfinished basement where the heater - without the basement, it’s about 900 sq feet of living space. I have no driveway or garage, and although I have a small lawn , it only gets watered if I have put down new grass seed. It’s probably no more or less eco-friendly than the identical house next door which has been divided into two apartments assuming the same number of people are living in the two buildings ( which is very likely). And my house/neighborhood is in the city, and therefore even a single person living in 900 sq ft SFH who walks and takes public transit* may have less of an impact on the environment that a person living in a 500 sq ft apartment in a more-car-dependent area.

* Many of my neighbors have neither driver licenses nor cars.

This Old House had one season where the objective in the house they were remodeling was net zero energy use, and this was not a small house – as is usual on TOH these days it was huge for the number of people living in it. They had a lot of solar panels and battery storage, and the house was extremely closely insulated and so on. If you want the whole story you’d have to watch the series, but there was nothing especially revolutionary about anything they did, everything was off the shelf. So it can be done.

How does $50, 000 starting price point sound? I googled the and looked. I am thinking about ordering one.

Elon Musk rents this pre fab, foldable, delivered to your site and set up for you house. Take a tour for yourself. The Boxable website has the options so you can see what they do.

A friend once owned a house somewhere in the upper midwest that was built into a hill and was mostly underground. If it had used heat pumps for heating and had solar panels on the roof, it would have been very eco-friendly. But in general it seems unlikely. There just are not so many hills to be built into. And then there is the commuting.

For many years I lived in a semi-detached house. The attached house faced mostly north and I must have benefited from that. Then I walked to my office in one direction and took a commuter train home in the other, so perhaps the net effect was fairly eco-friendly.

This is probably the biggest real-world factor.

If you were looking for a purely theoretical discussion, consider this: almost any new technology you could adopt for the single family home to reduce the environmental impact could, in theory, also be applied to the apartment, which would again make the apartment better than the house. The big issue is if you could make such changes in an apartment.

I think a key point that has been touched on, but not emphasized is footprint-per-person in said house or apartment. I own my 3 bed 1& 1/2 bath home with my wife, and previously had a 2 bedroom 2 bath apartment. Neither are of course as energy efficient as we would ideally like, but the costs of heating/cooling the empty space with just us and pets is certainly worse in the house compared to the apartment, amplified by the fact that the apartment was a @ 2000 constructed building, and the house was built in 1982.

But for my wife’s cousin, who has a single family home (3 bedroom, 2 & 1/2 bath) they have the 2 adults, and 4 kids (ranging from 10-17) living in just a bit over our total square footage. 6 people sharing resources would be nearly impossible even for relatively big apartments, and the efficiency increases in comparison. So I think part of the issue is the relatively recent trend of good sized houses with few people in them. Everyone in my parents generation (now mid 70s) has at least one, or more likely 2 siblings, but my generation (mid 40s) it’s often one, or rarely two.

Admittedly, this is for a generally middleish class of modern Americans, and there are plenty of exceptions, but a ‘starter’ single family home was generally built with the assumption of being good for 2 adults and 2-3 kids, which is much more rarely the case these days.

If you assume the same 4-5 people are going to exist in any scenario, then yes, having a house with 2 parents and 2-3 kids might be reasonably dense. But you can’t really say it’s more eco-friendly for those 2 adults to have 2-3 kids in the first place, versus just enjoying the extra space in that same house themselves.

Oh, certainly not, just pointing out that the seemingly normal ‘starter house’ for empty nesters is in and of itself an abnormality in terms of intended use, especially for those constructed prior to 1990 or so.

My intent is that on a person-per-square foot, most single-family homes are more efficient than many apartments given the expected residential occupancy. Admittedly with a large number of caveats, as micro apartments (say 300sq ft or less) and apartments with abnormal residency (4+ people in 5-600 sq feet) change the numbers.

How about this, the 1000+ sq ft single family home is incredibly inefficient for 2 person families, far less so for an expected family of 3+. :slight_smile:

I don’t follow the logic, because the same size and appointed apartment/condo still has the benefit of shared walls/ceilings/floors, single utility taps, and potentially much less land area if it’s a multi-story building. Sure a single-family home may be more efficient for larger families than it is for small families, but it doesn’t necessarily follow that an apartment (or are you saying multiple apartments?) for a much larger family wouldn’t still be more efficient than a detached house.

That’s the thing, while net-zero is definitely laudable, there’s an argument to be made for buying or renovating a small older conventional home versus building a new big home with all the latest tech. The old small apartment may still come out ahead of both of them because it’s already existing (embodied energy) and uses simpler more locally-sourced construction materials and methods. Just about all building materials today are synthetic and not recyclable, reusable, or repurposeable. So in a way you could argue that all big single-family homes should be net-zero, LEED Platinum, etc., just to mitigate all their other downsides.

What happens if you grow food instead of lawns and reduce your reliance on transported food? How much of a difference is possible? My SIL grows all the vegetables her family of 4 eats from April to October and cans some, and their lot is just a city-sized one

Single-family homes - or at least low-level apartment buildings, four to six storeys high - have the advantage, even in cities, of reducing the number of people in an area. That means fewer cars, and public transport that can actually cope (reducing the need for cars), and fewer people using electricity in that particular area.

(I see that you said to leave cars and public transit out, but it’s a natural part of the discussion).

Also, when it comes to flooding risks, you need plants, trees, and even lawns. Those outdoor areas are also better for allowing birds, bees, etc, to survive, as long as they are used for growing plants; if people choose to have virtually sterile lawns and not much else, that doesn’t help, of course.

That doesn’t really make sense. You’re not reducing the population; you’re just spreading it out, leaving less land for trees and such. And especially if you want to talk cars, you’ll be hard-pressed to avoid them if everyone’s in single-family homes. Public transit needs extremely dense housing to be workable. I said to exclude it from the calculations for two reasons: one, it was my living situation that inspired the question, and my husband and I had two cars even in the city. Two, if you assume the apartment-dwellers take the subway while the single-family homeowners drive, there’s really no way for the SFH to compete, and the question becomes less interesting.

It depends what kinds of single family home you’re assuming - though I did also include low level blocks. I live in inner London in an area where there are still a lot of single family homes, and public transport is everyone’s main mode of transport. The homes are small, and go up more than out, with small gardens - they’re not American suburban picket fence style homes.

I’m not going to assume that the single family home dwellers here drive, because I know for a fact that they don’t.

My house is divided into two flats that would be about 900 square feet in total; currently six people live here quite comfortably. Even when it was a single family home it would have been smaller than your calculations - I think you might be underestimating how compact houses in cities can be. If you’re expecting 500 square feet per person, that’s a problem no matter whether it’s an apartment or a house.

You’re reducing the population in comparison to having high rise apartment buildings. A block of four-story walkups houses fewer people than the same block full of 20 story high rises. It doesn’t necessarily mean the population is particularly spread out , and doesn’t mean the population isn’t dense enough for public transportation to work . It seems like people have a picture in their head of what an apartment is ( like they are all small- they aren’t ) and what a house is ( large and spread out - not all of them). Here’s a photo from a nearby street :
Is that one house with two apartments or two separate houses? In many places, that would be a duplex, a single house with two units and a single owner. In my area, it’s two semi-detached houses on two different lots with two different owners. But the difference is purely one of ownership - whether it’s two apartments or two houses, the eco-friendliness is the same. And as @SciFiSam said, you can’t just assume that people who live in single-family homes drive - lots of people in my neighborhood don’t drive at all , don’t own cars or only drive on weekends, taking public transit to work.

For a fair comparison, you need to be looking at the same number of people in both cases. And for the same number of people, the higher population density will always mean less energy spent on commuting. Not only does public transit work much better with concentrated population (so you can put a station at every high-rise apartment), but even if all of the high-risers were still driving their own cars, they would be driving them a shorter distance.