Insulate a log house in Houston
Hi, I now live in Houston with a background in restoration in the North East. One of the major differences for me between the North and South is vapor barriers. In my own older house I have installed inslulation with no vapor barriers. A friend has a weekend farmhouse not far from here. An 1860’s log house was added some years ago. The entire structure is climate controled year round. As the log addition has no insulation and water that hits the side of the building seeps through the logs and chinking she wants to put Hardiplank on the exterior with a vapor barrier between the hardiplank and the logs. I am not sure this is the wisest decision as I feel the building needs to breath. I am also not sure that Hardiplank is the wisest material as I don’t believe it breathes either.
Any thoughts on vapor barriers in the South would be greatly appreciated, particularly on this log building.
Thanks, Robin
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Local building officials would have a good idea of what works and what doesn't for your area. Generally in cold climates the vb goes on the inside, in hot climates it goes on the outside, and inbetween it can be either or none.
Here in Boise we used to install the vb on the inside of the insulation, now it's recommended that the walls do without a vb and on the ceiling it still goes on the inside. In reality, it is entirely dependant on the part of town, exposure, and interior temps, as fluctuations in either can cause condensation within walls.
We remodeled a house with clear vb and only stripped the sheetrock off in many areas. It was interesting to watch the morning sun warm the southern walls and cause condensation on the vb. Later, as temperatures equalized the condensation would go away. As the day went on and the AC kicked on, condensation would again show it's head in other portions of the house vb. This house would have been a good one to take pictures of because of the strange visual lessons it would show off each day.
Air travel paths within the insulation were also clear as day. The trail of black insulation would travel from exterior electrical outlets or other gaps in the siding and move up through the walls and out another gap.
Beer was created so carpenters wouldn't rule the world.