Does the Wire Mesh Cause Condensation in Straw Bale Construction?
Straw Bale Construction - A Community Member Question Answered
I have heard that metal in bales can cause dampness due to condensation does this not apply to the two inch welded grid (welded wire mesh)?
- Strawbale Community Member
The galvanized welded wire of the mesh is considered thin enough not to introduce a lot of condensation. Typically, a gauge size near 14 is used. (See an example of welded wire mesh here.)
The idea is that condensation forms when there is a drastic temperature difference, such as on the surface of the interior wall, to the middle of the bale wall, to the exterior surface of the wall. These may be very different depending on weather, time of day, etc.
The welded wire mesh grid does not fit that concept as it is so small it does not contain a temperature gradient large enough to introduce condensation.
Also, the location of the mesh is embedded in the water-loving natural plaster on the surface of the bale, further reducing the impact of the metal on this point.
An example of condensation can be seen in an older practice of using a rebar in the center of bale walls to stabilize the wall itself. Over time, this practice has fallen by the wayside as it was discovered in some regions that there was a core of rotten straw around the rebar… right where the condensation was occurring.
As in all construction types, technology and best practices are evolving over time. One of our favorite aspects of the natural building community is how the members share their learnings with others interested in building better with bales.
Whether it is at a CASBA conference or around the campfire at one of our workshops, the volume of experience in this community is truly inspiring!
