Is a rainscreen mat more important than exterior insulation if only one can be installed behind fiber cement cladding?
MikeonLI
| Posted in General Questions on
Homeowner Long Island NY. Having new fiber cement siding installed soon. Everything has been finalized but there is still an open question about whether to use a rainscreen mat or exterior insulation over the wrb. I can’t do both because of minimal overhangs on the house.
I really like the idea of exterior insulation taped at all the seams for thermal and air sealing properties, but it seems that having a rainscreen there, especially in my area that gets a lot of rain and with a house that doesn’t have overhangs, is the wiser choice. All comments appreciated
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Replies
In the hierarchy of control layers water management is the top dog followed by air management. With minimal overhangs, I would prioritize water management which when done correctly nearly solves air management at the same time.
A self adhered WRB like Henry Blueskin VP 100, Siga Majvest, Proclima Adhero or HydroGap from Benjamin Obdyke coupled with window, roof and base flashings are all good options. If you have room for a rainscreen made from 1x3 furring I find that to be one of the best options otherwise an entangled mesh material might be you best bet.
Thanks Jeremiah! Good tips!