Hacker News Reader

Comment by johndhi | Hacker News Reader

Any tips for me? I live in Northern California in a house that (1) has an empty space below it, (2) single-pane windows, (3) an inefficient fireplace with no steel stove, (4) a big, cavernous room with high, un-insulated ceilings on one half of the house.

Obviously we could spend a zillion dollars to insulate everything and fix all of the problems I identified above (and probably more), but what is critical?

One thing we started with is putting a thermal curtain between the big, drafty room and the rest of the house so that the thermometer doesn't get triggered by the big room sucking the hot air out of the rest of the house.

View on HN

1. I would start by lowering the ceiling and insulating it. For ceiling if you insulate it using mineral wool, or glass wool... the vapor barrier [0] is critical and must be placed continuously on the warm part. Also this membrane (preferably containing aluminum so that you get back some of the heat) must be glued to the walls using special glue [1]

2. I would change the windows, with at least triple pane. The windows must be mounted correctly (see RAL montage) and also must be placed aligned with the outside face of the wall.

3. I would take out the floor, and do hydronic underfloor heating with EPS150 or XPS as insulation substrate.

[0] https://www.rothoblaas.com/products/airtightness-and-waterpr...

[1] https://www.rothoblaas.com/products/airtightness-and-waterpr...

Thank you!

what price do you think we're looking at for each of these? lowering the ceiling is a bit of a bummer from a looks perspective. underfloor heating sounds wonderful.

You're welcome! I live in Europe (Romania) and to be honest I would not know what to expect in terms of costs. You lose at least 25% of your energy trough the roof, this can even go up to 30-35% if the ceiling is cracked or air is able to circulate freely trough it.

The bigger the room, the higher the ceiling has to be to feel comfortable. I'd still insulate the ceiling of the big room, but I wouldn't necessarily lower it. Instead, put in a ceiling fan so that the air doesn't stratify. Fireplace isn't critical unless you're actually using it for heating.

Reply on news.ycombinator.com