Airsealed the basement!

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laynes69

Minister of Fire
Hearth Supporter
Oct 2, 2006
2,677
Ashland OH
I finally broke down and airsealed the basement. I bought 1" foam board and cut pieces to foam into place. On the sill beam (old home) I used 1", but in the addition I used 2" foam. Already I've noticed a difference. I pulled a vacuum on the basement and used an inscense stick to look for drafts. Also I mixed mortar and replaced loose or cracked mortar in the stone foundation. Once it gets cold I will be able to tell more of a difference, but so far so good! Our home is at least 150 years old, so it has its issues!
 
That should make a nice difference. Does the furnace have an outside air supply?
 
That should make a nice difference. Does the furnace have an outside air supply?
LP furnace yes, woodfurnace no. I went to bed last night and the house was 73 degrees. It dropped to 48 last night, windy and damp. Usually when I wake up the downstairs is cooler than upstairs but the temperature felt warmer. When I looked over at the thermostat, the house was 73. I honestly can't believe the difference!
 
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LP furnace yes, woodfurnace no. I went to bed last night and the house was 73 degrees. It dropped to 48 last night, windy and damp. Usually when I wake up the downstairs is cooler than upstairs but the temperature felt warmer. When I looked over at the thermostat, the house was 73. I honestly can't believe the difference!
That's impressive on that big ole farm house!
 
LP furnace yes, woodfurnace no. I went to bed last night and the house was 73 degrees. It dropped to 48 last night, windy and damp. Usually when I wake up the downstairs is cooler than upstairs but the temperature felt warmer. When I looked over at the thermostat, the house was 73. I honestly can't believe the difference!
Yes, when I sealed up and insulated the crawlspace the difference was quite notable.
 
Well as an update, the temperature dropped down to 23 degrees last night. I loaded the furnace at 9:30 pm with a 3/4 load, got the furnace hot and set the thermostat for 73 degrees. I woke up 7:30 AM, house at 73 degrees and it was 24 degrees outside with a 5" coalbed in the furnace. The difference is night and day!
 
This will be one of the coldest nights so far this year. Currently its 18 out with a windchill of 6 degrees. Since santa is coming I decided to load the woodfurnace so I could get to bed. The house is 76 degrees and much to my astonishment, the firebox had all coals that were washed over and blower on the lowest setting. Walking around in the basement I would never know it's that cold out. Well worth the effort!
 
This will be one of the coldest nights so far this year. Currently its 18 out with a windchill of 6 degrees. Since santa is coming I decided to load the woodfurnace so I could get to bed. The house is 76 degrees and much to my astonishment, the firebox had all coals that were washed over and blower on the lowest setting. Walking around in the basement I would never know it's that cold out. Well worth the effort!

I air sealed and fully insulated my unfinished walk out basement last year. The difference was staggering. It was 12 degrees the other day and the basement never dropped below 60. If done right your basement will stay the same temperature as the floor/ground temperature.

Is your foundation insulated? I put R10 foam board on my poured concrete foundation and the results were amazing. Concrete has basically no r value and just transfers heat right out your house.
[Hearth.com] Airsealed the basement!
 
No, I just sealed the sill (old beams). Half of our basement in block and the other half is almost 3 feet thick with boulders. Fortunately having the woodfurnace in the basement, it keeps warm. I would like to insulate the walls, however it will be quite the project!
 
20 some years ago (before I bought this place) we looked at an old farmhouse that had been totally gutted and remodeled (it was gorgeous...had free gas too! Just slightly over my absolute maximum price range though) it had the typical old stone foundation, and the basement had been totally finished.
What they did was came in 16-18" off the walls and framed in new insulated walls...most of the wiring and plumbing was kept out in the perimeter, where it was fairly accessible, including the breaker panel...they kept a dehumidifier running in that outside area too.
When you were in the finished area the only thing that gave away something was "off" was the super deep "window wells" (from the inside)
 
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I'd like to do some sort of internal perimeter drain before doing something like that. I still have alot to do before I get there. I did notice that the dehumidifier didn't run near the time after doing it.