This message has been cross posted to the following Discussion Forums: Custom Residential Architects Network and Housing Knowledge Community .
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Rand:
I appreciate the research on 15# felt verses Tyvek - type houssewraps. One concern I have is the durability of current 15# felts. Many of the renovations we have performed were built +/- 50 years ago and were built using a 15# felt. When the wall cladding (brick veneer or wood siding) opened, the felt is frequently very brittle. The houses and their exterior cladding seem to outlive the life of the felt hidden inside. This is also the case with older tile and slate roofs where the underlayment becomes the weak point for water entry.
Has the formula for currently available felts been improved such that it extends the life of the underlayment?
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Kevin Harris FAIA
FAIA
Kevin Harris Architect, LLC
Baton Rouge LA
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