Dense-Packed Double-Stud Wall – Sheething or Membrane?
Starting a build shortly with a 12″ double stud wall dense packed with cellulose. The interior wall is 2×6 and load-bearing, and has Engineered shear panels located inside. The exterior wall is 2×4 and has no Engineered shear value, it’s just there to hold the insulation and siding, similar to a Larsen truss design.
I was originally planning to sheet the walls with Zip or ordinary OSB+adhered membrane, but ludicrous material prices has led me to ponder the value of that sheething and to consider another approach I’ve seen used; a sheet-less wall with a dense-packable WRB membrane on the exterior.
My original plan was to build a windowless sheethed box and do my first round of air-sealing before any penetrations were involved or any plumbing, electrical or insulation had started.
Using just a membrane on the exterior, what pitfalls am I potentially setting myself up for? Concern: similar to a vapor retarder installation, is whacking several thousand staples through this exterior membrane going to compromise its airtightness? I’ll be some screwed if I fire up the fog machine and there’s an air leak or two at every staple – I’ve got my sights set on an extremely airtight enclosure.
Are there any other considerations I’m missing? Looking to leverage the experience of builders who are more experienced than I (first time builder/homeowner here) as well as those who may have used this approach before. Any case studies or build blogs you can refer me to?
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