In bale construction, plaster should be applied directly to the straw to avoid gaps behind paper and stucco which could create air channels. Voids between courses of bales should be solidly and firmly filled with straw, straw-clay or plaster. A much greater threat to buildings in temperate climates comes from rainwater penetration of the building envelope. Wind-driven rain accounts for most moisture damage within wall systems. Careful attention to detail, sealing of all penetrations and control of crack and fissures are vital and cost-effective ways of preventing moisture from entering the envelope.
Regular maintenance can reduce the possibility of failures over time.
It should be recognized that no building system is perfect, and that some wetting will occur. The ability of a wall system to dry and store moisture, as well as its resistance to wetting, are of great importance in reducing its vulnerability to moisture-related damage and deterioration. Bale walls are made up of millions of individual straws that can absorb and disperse relatively large quantities of moisture. Compared to wood fiber, straw is loose, and provides greater opportunity for capillary movement and moisture storage. The mass of a bale wall is greater than wood-frame, and that material is more readily available for moisture transport and storage because of its low density and porosity.