Housing Change for Climate Change

For a little over a year, when I lived in Ithaca, New York, I worked for the Ithaca Green New Deal. This was a pretty ambitious city goal to reach carbon neutrality community-wide by 2030. In a city like Ithaca - an old, northeastern city - buildings make up 49% of greenhouse gasses in the city, largely through heating and cooling. Obviously, if the city want’s to reach carbon neutrality, those greenhouse gasses need to be abated.

How do we do that? Well, we could force everyone to endure hot summers and cold winters without reprieve, but that will probably hasten revolution, so is not ideal. Alternatively, we could improve the heating and cooling efficiency of our buildings. That’s actually possible; by installing upgrades like reversible heat pumps and other modern retrofits, we can squeeze more cooling out of every Watt. For heating, most of the chemical energy available in a unit of natural gas is already extracted by modern boilers and furnaces, but heat pumps here too come out ahead, and can transfer up to 300% more energy than it consumes, compared to the measly 98.5% of the top boilers and furnaces.

Unfortunately, top-of-the-line equipment can have a daunting price tag, deterring consumers (particularly in lower-income brackets) even if the tech pays for itself over time. Also, these improvements are useless if we can’t get the air to stay where we want it. Ensuring that our buildings are sealed, and therefore not losing precious energy to the outdoors, is and should be a major goal of retrofitters and dads everywhere. Making a building 100% air-sealed is pretty much impossible, but there are many ways to get close. Some of these options are fairly cheap - re-caulking and installing weather strips can have a truly outsized effect if your building needs it - while others are a bit more expensive but also lend great benefit, such as installing double- or triple-paned windows or upgrading insulation. Ultimately, the goal is to ensure that air inside the house stays in the house while air outside the house stays outside the house.

Oh I just can’t help br-eathin’

This is all well and good, but for one thing: fresh air. We’ve all had the experience of being cooped up inside all day and finally stepping outside, only for your lungs to be greeted with that pleasant and bright feeling of fresh air hitting our lungs. This feeling isn’t just in your head - the air outside is markedly different from the air inside. Air quality indoors is routinely 2-5 times worse than outdoors, and it can get up to 100 times worse under certain conditions. Things like carbon monoxide, nitrous dioxide, carbon dioxide, teeny-tiny particles - often referred to as PM 2.5-PM 10 based on the size of the particle (Particulate Matter=PM, 2.5=2.5 micrometers) - and nasty chemicals referred to as Volatile Organic Compounds (VOCs) all accumulate in your house and can have serious health effects ranging from asthma to reduced cognition. While some of these air particles can come from the outdoors, many originate from things like cooking, heating, cleaning, and simply breathing. Well ventilated areas can mitigate much of this, and simply opening a window can improve air quality drastically.

Ambivalent Ambience

Maybe you’re beginning to see the problem - we want our temperature-conditioned air to stay inside the home while at the same time running the risk of serious health consequences if we breathe that air. Snagging fresh air from the outside before changing its temperature with something like a heat exchanger might work, but this poses a problem too. It is far easier to warm 60 degree air to 70 degrees, or cool 80 degree air to 70 degrees than it is to change extremes to a more reasonable temperature. This means that, if we want to conserve energy, we will likely always be recirculating air inside the house. Some technologies like energy recovery ventilators - which use temperate exhaust air from the house to warm or cool incoming fresh air - are clever ways to mitigate this problem a little, but ultimately they’re not as efficient as a completely sealed home.

Breathe Easy

A common solution is to filter out the bad stuff from the air, and we’ve made a lot of advancements in filtration in recent years, with HEPA filters now capable of capturing nearly all particulate that passes through them. While standalone, full-home-capable, air purifiers can be expensive, flat filters which can be installed in your heating system - or simply attached to the back of a box fan - can be purchased for a pretty cheap price. This is a pretty solid option if you stay on top of it, but if you’re anything like me you will not stay on top of it. Further, these filters are wonderful at reducing particulate and dust, but won’t solve molecular air quality issues like those from VOCs or carbon monoxide.

The best, long-term option, as far as I can see, is reduce the in-home sources of these deleterious compounds. This includes replacing gas boilers and furnaces with heat pumps (ideally reversible heat pumps that work as air conditioners (and ideally ground-sourced heat pumps, at that)), replacing gas stoves and ovens with electric ranges, implementing kitchen hoods where they don’t already exist (like my old apartment, which was a breach of NY Building Code!), upgrading to outdoor venting hoods when possible, and just generally reducing the amount of times we have to burn anything in the home. The more we can do to upgrade existing homes, and implement codes requiring new homes to be built, to limit these airborne chemicals and molecules, the more we can focus on achieving environmental sustainability without risking people’s safety in their own homes.