The walls; our brick walls get full sun for most of the day and that heat was going straight into the interior plaster, which is about 1" thick, and thence into the house. We shopped around for contractors, looking specifically for someone to use cellulose insulation as that is not only more sustainable but also less toxic. Not a single one would use it! They all use fiberglass. As the walls are sealed I believe we are avoiding exposure to the fibers, which have recently been listed by the EPA as a carcinogen, but we had to compromise on the sustainability aspect.
Being on a tight budget we have long ago reconciled ourselves to compromise when it is necessary. One of the rationales in this case is that the material is going to help us reduce our use of fossil fuels by improving the thermal efficiency of the house. Over time we hope this savings will offset the damage done in the manufacture of the less sustainable material.
|On the North side, insulation first, metal on top, good riddance to the asphalt!|
And oh what a difference this has made. Normally the upstairs renovation is 15º to 20º hotter than the downstairs. Now at most it has been 5º warmer. When we got up this morning, the outdoor temp was about 68º while indoors it was 74º. We embarked upon our usual practice of aggressive ventilation during the cool hours of the morning. The temp held firm at 74º. I believe this was due to the outdoor temp staying relatively cool for most of the morning as it was raining. Eventually the temp indoors dropped to 73º and later, as the outdoor temps got up to near 88º with full sun, our indoor temp rose to 75º. When I cooked a zuchini casserole in the oven at the hottest time of day the indoor temp climbed to 77º downstairs and up. I'm stoked! Essentially we've changed the way the house responds to temperature changes, slowing down it's response. This is good, as the indoor temps will likely be at their highest in the evening when the outdoors is cooling off we will be able to draw that cool air into the house to drop the temps which will continue to drop through the night as the walls will not be collecting heat from the exterior bricks. I'm betting we will not need the AC at all now. Additionally, in the winter the extra insulation should drastically reduce the amount of wood we need to burn to stay warm.
So far so good, but tomorrow, the solstice, the temps are supposed to reach into the low nineties. That'll be the real test.
|the south side|