I’ve encountered that term, or some variation of it, a kazillion times. It’s taken over the world. Let’s look for a window at the Orange Place. Right out of the gate, no warmup, we get:
Learn more about energy star performance ratings, glass types, and the benefits of energy efficient patio doors and windows
Please note that no mention is made of the fundamental reasons to have a window of any kind. What is a window for? According to everyone, it’s for saving energy, and maybe something else, we’ve forgotten. Did we mention it’s premium vinyl? Now there’s an oxymoron for the ages. But we’re assured that premium vinyl is peachy, because it saves energy.
This is what a window is for. Remember, you heard it from me first, which is a testament to how weird everything’s gotten:
- To admit light
- To frame views
- To admit fresh air
- To withstand weather
- To allow emergency egress and ingress
- To provide security
- To save energy
I skipped a bunch of things because I got bored, but you get the picture. The window cart has been placed before the horse, rolled backward, and crushed it.
So I’m not trying to save energy with my insulation project. Saving energy is a downstream effect of what I’m trying to do. It’s collateral damage. I’m trying to:
- Keep me from re-enacting the end of the Shining
- Keep my kids from drawing unflattering caricatures of me in the rime on the inside of the windows
- Keep the ketchup in the pantry from freezing
- Keep the ketchup in the refrigerator from freezing
- Keep the cat from moving next door
- Keep from burning the furniture for heat
- Keep from waiting until spring to coax my wife to remove at least some of her clothes
- Keep from spending my entire income on heat
That last one looks vaguely like “saving energy,” I’ll grant you. But I don’t want to save energy. I want to use energy to make our lives better. I’d like it to be cheaper, but I’d like rain to be beer, too. No one asked me how much it should cost. So if I can accomplish the first eleventy things on the list by giving at least a sidelong glance at the last item, so be it.
We’re going to have to use a mixture of insulation materials to accomplish anything meaningful and comprehensive. The plan with have to be done on a shoestring, with the shoestring laced into a dwelling shoe that need cobbling, to strain a metaphor. Let’s run down the likely choices:
- Regular spray foam
- Closed cell spray foam
- Fiberglass batts
- Rock wool batts
- Rock wool loose-fill
- Cellulose loose-fill
- Sheets of polyisocyanurate
- Sheets of polystyrene
Well, you can forget spray foam. Either kind. Whatever benefits it brings to the table are more than offset by how much it costs. The internet is cagey about actually telling you what things cost, because they’re all trying to sell you things. These fine folks took a crack at it, though. I can’t testify to their accuracy, and “costing” is a word, but it’s not the word they’re looking for, but whatever.
Yeah, spray foam ain’t gonna happen. And poking around, I realized these are 2010 prices. I don’t know what things are like where you live, but some stuff costs more now than a decade ago where I live and shiver. I have trouble remembering way back then, but I’m pretty sure eggs didn’t cost a buck apiece.
I don’t like spray foam anyway. It has drawbacks you’re not going to hear about over everyone screaming SAVE ENERGY, and logrolling shelter shows to tout the stuff. Spray foam burns. And when it does, many kinds of spray foam insulation emit a cloud of toxic gas that would make a North Korean chemical weapons manufacturer proud. It’s good at air sealing, of course, but you can so that sort of thing with little cans of foam followed up with cheaper insulation. And when they tell you that it’s got a higher R-value (resistance to heat passing through) per inch than other insulation, they neglect to tell you that there’s a limit on how thick you can make it. The benefits of adding more thickness drop off fast. And I hate filling up wall cavities with stuff that doesn’t budge. Try fishing a wire in a wall filled with the stuff, and see if you still think it’s swell.
You can spray a fire-retardant coating on spray foam to avoid ignition. It reminds me of the old story that begins with getting a cat to get rid of the mouse, and ends with “in the winter, the gorillas freeze to death.” I like to avoid problems. It’s easier than solving them.
Hey, in that chart above, look at cellulose. It’s cheap.
I looked into cellulose, hard.
- Is it really that cheap? Yes
- Is it fire resistant? Yes. It won’t burn
- Is it cheap? Yes
- Can I get some? You bet
- Can I install it myself? Yessir
- Is it cheap? I’m glad you asked me. Yes, it is
So why doesn’t everyone use the stuff? A couple of reasons. Wily foam manufacturers aren’t going to take no for an answer. They logroll more than teevee shows. They get SAVING ENERGY rules passed that make R-Value per inch the ne plus ultra of SAVING ENERGY. They figured they could never compete on price unless they basically outlawed batt insulation and loose cellulose.
Hey, wait a minute, who said it had to be loose? Other people are clever, too, and come up with ways to use existing, inexpensive materials in new and improved ways. I discovered dense-pack cellulose insulation, and never looked back.
[To be continued. Thanks to everyone who reads, comments, tells a friend about Sippican Cottage, buys a book, and hits the tip jar. It is greatly appreciated]