Open or closed cell spray insulation?

Closed cell. It has a built in vapor barrier, so you don't have to worry about moisture between the sheets and insulation. It costs more than open cell but has a higher R value. I had 2" closed cell foam sprayed not long ago and the temperature difference from before it was sprayed to after was crazy.

ETA: It also adds rigidity to the sheets so its a lot stronger. BTW, I'm also in Arnaudville. If you need a good foam guy let me know. The guy I used did great work and price was unbeatable.

It isn't a simple answer.

Closed Cell:
Closed cell foam provides higher R values per inch and is a bit better at sealing/infiltration depending on the depth of fill of the open cell you are comparing to. The biggest problem with closed cell is if you have wood studs. The expansion and contraction of wood will cause the closed cell foam to separate from the wood. this completely eliminates any infiltration advantage closed cell has as the years roll by. It is VERY rigid once sprayed. It is great when spraying on concrete or similar surfaces. It is VERY poor at sound dampening

Open cell:
Open cell has a lower R value per inch but it is much more forgiving. It is better at filling larger cavities. Once you get to 4"+ depth of open cell, it is just as good of a vapor barrier and infiltration sealer as closed cell. It moves with structures as they expand contract w/out being compromised. It is better at sound dampening but not great.

Personally, I would use neither in above ground framed walls. I like to used open cell in rim joist insulating applications. I like closed cell on basement walls.

I would recommend looking into blown insulation for your walls. Take dense packed cellulose for example. You can still get high R ratings and VERY good infiltration reduction but it also has the benefit of being much cheaper AND it is a very good sound dampener.

Spray foam isn't as great of an all around solution as some will portray. take the time to analyze all the choices. there really is no payback when talking above ground walls for spray foam compared to blown insulation.

Very nice information. I stick framed it and wrapping in metal

LSU ag center has some very good info at

La House Resource Center

Matt Risinger loves closed cell. He also like Rockwool which is something to think about as a possible alternative or way to cut costs

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I’ve heard some local radio shows talk about how they wouldn’t recommend cellulose in humid climates. What’s your take?

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Not an issue as long as vapor barrier is installed properly and in the correct location within the envelope system.

The envelope is a system. The siding, sheathing, vapor barrier, drywall, and of course insulation must be designed to work together for each varying climate. They will all impact each other.