Curtain truss

Curtain truss

Nonstructural truss that extends from a structural wall system solely for the purpose of holding cavity-fill insulation known also as a Larson truss. Often used on timber-frame houses and in super-insulation retrofits, curtain trusses may be as much as 12 inches deep, providing an insulating value greater than R-40. Since they aren’t structural, curtain trusses are often constructed from 2×2s with plywood reinforcement flanges to minimize wood use.
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