Cool Science

It's the time of year when I get really annoyed at how often our heat comes on to maintain our house at a pretty modest temp. After all, we live in a tiny little cottage-style home and it should be cheap as hell to heat this place and it shouldn't feel like the inside of a fridge.

When we first moved in to our fair abode, we couldn't be there for the home inspection, and as far as I can tell the guy just phoned it in. That's a disappointment but I've made my peace with it for now because we anticipated a lot of the issues for ourselves. But the biggest surprise probably was the "insulation". I have to use quotes because when I poked my head into our little attic space I was horrified that about 20% had no insulation and the rest had 2-3 inches of crumpled up mess. I happily took care of most of this and smugly indulged in way too much diy pride.

But incredibly the house was as cold as ever, especially upstairs. "How", I wondered, "could I have taken major tracts of ceiling from no insulation to R-34 and see no return?". It must be the windows right? They give us a nice breeze whether they're open or not. But our house has about as many windows as our four door sedan, so that can't be it. I sat on it for a while, stewing.

Then for a birthday (I think?) I got this awesome surface-scanning thermometer gun that I'd wanted for a while (initial motivation was to monitor the temperature of my smoker without lifting the lid). And I wanted it out of sheer gadget-envy too, ok. I was reading the literature that it comes with, and that was annoying because it didn't explain the science. Closest I could figure from the vague description - and this strikes me as a little unlikely - it may do a blackbody radiation analysis, which I find surprising for the temperature range it covers. But the one reason why this might be right is that blackbody radiation is theoretically independent of the material (not quite true in reality), a very desirable property of a surface scanning thermometer. But even if I can't find a source on the science, I can see plainly that it works.

And I was surprised at how good the good precision was, and realized I could use this to start hunting for variation in wall temperatures. It's so good I can use it as a stud-finder.

And I now know why our house is still cold. First (cue the 'ironic surprise' music) large tracts of ceiling that were not visible to me from the attic are not insulated and it was really easy to spot with the thermometer from inside the rooms; and I went spelunking in crawl spaces and found it. Yes at least 50% of our ceilings were not insulated at time of purchase. I see in hindsight that after I fixed the attic, it dropped to maybe 30% of our ceiling being uninsulated. If I ever meet our home inspector I don't know if I'll be able to be civil. So I'm about to start on putting that missing insulation up.

Second, 60 year old insulation is really, really bad. I replaced an original batting with a combination of styrofoam board and new batting and saw the wall temperature increase 3-4 degrees over a region with old insulation. So I'm now on a humbug to go through and do that all around also.

Those two are the biggies - I found a bunch of other problems less interesting to mention here. So, if your house feels cold don't be a dope like me - there's probably an obvious, fixable reason and a cheap surface thermometer gun will at least make it fun to discover how the person before you bungled the insulation.