EcoRenovator - View Single Post - AC Insulates Under Floor of 120 Year Old Crawlspace

SDMCF · 09-01-14, 02:24 AM

Interesting project.

My house was also built in the 1890s and also has a crawl space, but the similarity ends there. Your crawl space is a lot more spacious than mine, and it looks like it is more open/light. The construction of yours is more modern/industrial compared to mine which is more backwoods style.

The main difference though is the floor construction above the crawl space. Is the visible boarding the underside of your floorboards? If not, what is there above that boarding?

Looking up in my crawl space you just see tree trunks rather than joists and boarding. The whole floor is solid tree trunks looking from underneath, and is floorboards when looking from the top. I have no idea what, if anything, is between the tree trunks and the floor boards. I have considered adding insulation under the flooor similar to your project but have not done so for 2 reasons. Primarily because I have been unsure of the implications as regards ventilation and inducing rot in the woodwork. Everyone I ask has different views on that and there are plenty of horror stories about people getting this wrong and causing major problems for themselves. What are your views & plans on this?

The other issue is restricting the space even further when it is difficult to move around under there already. Your insulation will (I think) be up above the joists and so will not restrict movement, but I have no joists as such and any insulation would just lower my crawlspace "ceiling". That is maybe not too important as there is rarely any need to get under there.

09-01-14, 02:24 AM	#2
SDMCF Apprentice EcoRenovator Join Date: Jul 2014 Location: Finland Posts: 125 Thanks: 5 Thanked 35 Times in 34 Posts	Interesting project. My house was also built in the 1890s and also has a crawl space, but the similarity ends there. Your crawl space is a lot more spacious than mine, and it looks like it is more open/light. The construction of yours is more modern/industrial compared to mine which is more backwoods style. The main difference though is the floor construction above the crawl space. Is the visible boarding the underside of your floorboards? If not, what is there above that boarding? Looking up in my crawl space you just see tree trunks rather than joists and boarding. The whole floor is solid tree trunks looking from underneath, and is floorboards when looking from the top. I have no idea what, if anything, is between the tree trunks and the floor boards. I have considered adding insulation under the flooor similar to your project but have not done so for 2 reasons. Primarily because I have been unsure of the implications as regards ventilation and inducing rot in the woodwork. Everyone I ask has different views on that and there are plenty of horror stories about people getting this wrong and causing major problems for themselves. What are your views & plans on this? The other issue is restricting the space even further when it is difficult to move around under there already. Your insulation will (I think) be up above the joists and so will not restrict movement, but I have no joists as such and any insulation would just lower my crawlspace "ceiling". That is maybe not too important as there is rarely any need to get under there.