I am going to side my house with vinyl siding. I will be tearing the wood siding off and the plan is to use insulation board covered by housewrap. Which insulation board should I use? A foil faced product or unfaced product like blue-board? I will be using a 1/2" thick product either way.
Exterior Insulation Board Opinion
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No foil; exterior should be as vapor open as possible. While at it, can you install one or two inches of insulation and a rain screen? Are you installing a WRB (water resistant barrier, like Tyvek or asphalt paper)? 1/2" is almost not worth the trouble, IMO.
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I have thought this thread would help but I am still not entirely sure which insulation board would be best for this project. I am pulling the old siding off and need to reside now that I have installed the new door and windows. It occurred to me that I should probably pull down the spacer wood and just put up insulation board to even things up before I install the new siding. I was thinking 1 inch polystyrene board but not sure if i should be using foil faced or not. From what I have read I understand I do not want foil sided board in this application. Any thoughts?
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It could depend on if the original house has a vapor barrier on the inside. If it does then you do not want to have another on the outside. If no vapor barrier inside I would use 1" polyizo foil face and tape the seams. This will be your rainfall.
You may not get a lot of extra r value but you will create a conductive thermal barrier. Which you will want to have.
Id remove the old nailers and install the polyizo right over the siding. You can put nailers on top of the polyizo if desired and create an air gap which can help in heating n cooling. Again just want I'd do.
Hope that helps a bit
You may not get a lot of extra r value but you will create a conductive thermal barrier. Which you will want to have.
Id remove the old nailers and install the polyizo right over the siding. You can put nailers on top of the polyizo if desired and create an air gap which can help in heating n cooling. Again just want I'd do.
Hope that helps a bit
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Yes that helps, thanks. It does have a vapor barrier inside since i had the walls apart and put 4 inch of paper backed fiberglass up. I was just under the impression that today 4 inches of fiberglass was considered insufficient. You mentioned a air space between the siding and the existing exterior wall in this case old siding) and the new siding. I plan on hanging aluminum siding back up and was planning on nailing or screwing it right to the insulation and through to the old siding. Do you see a problem with this plan.
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