Huge energy savings thanks to re-insulating our attic last year

[mrs sideways]

Every summer, our attic was acting like an oven sitting on top of our house. When we installed a new roof, we had the attic done at the same time: they sawed out new venting along the sides, and added "Ridge Vents" along the entire upper ridge. This was key, as now the hot air simply rises up and out of the attic, sucking in cooler air behind it. They also sprayed a bunch of new insulation over the 1950s-era stuff that was already up there.

The results are stark. We open the house up overnight and then shut everything first thing in the morning. While our neighbors--on both sides--are turning on their AC at 8-9am, we skate by until 2-4pm (when the inside temperature hits around 80 or so) and we only have to run sparingly it for a few hours.

Will it take a long time to recoup the cost? Probably. But we get to feel smug whenever the neighbors fire up their AC units.

[Fishindude]

This is almost always the best place to spend money in regards to energy savings.

[soily]

I fantasize about building a new house just so I can insulate the bejesus out of it. How much did doing your attic set you back?

[MudPuppy]

Our house is on the newer side, so the attic insulation is okay, but we got an insulating tent to put over the pull down entrance hatch (not sure what the actual name is) and you can really feel the difference in air temperature in the hallway now!

[mrs sideways]

I fantasize about building a new house just so I can insulate the bejesus out of it. How much did doing your attic set you back?

According to the invoice, the attic insulation (which was subcontracted to a separate company) was $3200. The vent installation was, as far as I remember, rolled into the cost of the roof itself ($17k). Bear in mind we live in Silicon Valley and ALL contractor work is more expensive here than in other areas. We're probably saving about $75-$100 a month during the summer months, which isn't huge, but hey, we HAD to put a new roof on. We're glad we paid more to do it right, even if it'll take 8-10 years to make it back on electrical savings.

I think the venting was just as important as the added insulation. AFAIK ridge vents are common (if not standard) in new construction, but our 50s-era little ranch home didn't have them.

[mrs sideways]

I don't know how much heating you have to do in Silicone Valley, but you're going to notice a significant reduction in the cost / energy it takes to keep your house toasty in the winter too. Attic insulation is wonderful for all seasons. I added cellulose insulation to my 1921 house a few winters ago and my heating and cooling bills have nearly halved and the house is much more comfortable to live in. Congrats!

Good point. Especially because (IIRC) cooling with electricity is actually greener than heating with gas, so heating should be part of the attic discussion.