Rim joists first – highest ROI, low cost, easy DIY. Then attic air sealing not just insulation. Then walls if budget allows. Fix windows last since they are expensive relative to energy savings.
Vented crawl space plus open cell equals bad news in humid climates. Open cell is vapor permeable so it absorbs moisture at those humidity levels. Should have been closed cell with the crawl space sealed.
In the PNW you are in climate zone 4C marine. Closed cell foam at 2 inches plus already functions as a vapor retarder Class II. Most code interpretations do not require an additional vapor barrier with sufficient closed cell.
We use closed cell for anything below grade or on exterior walls in cold climates. Open cell is great for interior partitions for sound but not for an exterior wall in zone 5. Vapor drive in winter will push moisture into that open cell.
Agreed, it is just oxidation. If the foam is in an attic with any light penetration it will yellow faster. Performance-wise your R-value and air seal are unchanged.
Agreed, it is just oxidation. If the foam is in an attic with any light penetration it will yellow faster. Performance-wise your R-value and air seal are unchanged.
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Mike T. (TX) posted in Contractor Talk: "Best temp settings for 2lb foam in summer heat"New article: "Spray Foam R-Value: The Complete Guide" — Read it nowSarah K. (OH) rated a contractor 5 stars in ClevelandWebinar: Cold Climate Installations — June 18 at 2PM EDT — Register Free28 new members joined this week!Texas Chapter Meetup: June 24 in Dallas — RSVP nowFoamPro_Dave replied: "Graco vs Gusmer after 8 years — my verdict"Mike T. (TX) posted in Contractor Talk: "Best temp settings for 2lb foam in summer heat"New article: "Spray Foam R-Value: The Complete Guide" — Read it nowSarah K. (OH) rated a contractor 5 stars in ClevelandWebinar: Cold Climate Installations — June 18 at 2PM EDT — Register Free28 new members joined this week!Texas Chapter Meetup: June 24 in Dallas — RSVP nowFoamPro_Dave replied: "Graco vs Gusmer after 8 years — my verdict"
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