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Community and Q&A

For Chicagoland region, what type of insulation with vinyl siding is recommended?

gVWL4J9YER | Posted in Energy Efficiency and Durability on

I cannot afford the insulated vinyl siding, so I am looking at some type of fan-fold foam insulation – or flat insulation, then a Tyvek material, then the vinyl.

And does the thickness of the vinyl — .040 – .046 — really make any difference in strength and for insulation?

Thank you for any information you can enlighten me with.

Sincerely, jan

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  1. GBA Editor
    Martin Holladay | | #1

    There is no evidence that thicker vinyl siding lasts longer than thin siding. However, since thicker siding is stiffer, it may look better on the wall and be more likely to appear straight rather than wavy.

    I strongly urge you to install the thickest rigid foam insulation you can afford under your new vinyl siding. Since siding replacement jobs are rare, you have an opportunity to improve the thermal performance of your house, and you won't get a similar opportunity for several decades. For more information on this topic, see Roofing and Siding Jobs Are Energy-Retrofit Opportunities.

    If you install thin foam, you may end up with moisture problems in your wall. Thicker foam is safer than thin foam. In your climate zone (zone 5), exterior rigid foam should have a minimum R-value of R-5 if you have 2x4 walls, or R-7.5 if you have 2x6 walls. More information on minimum foam thickness can be found here: Calculating the Minimum Thickness of Rigid Foam Sheathing.

  2. gVWL4J9YER | | #2

    thank you for answer #1 - i am told there is another response from a dan?? - but can not find it - only #1 from martin comes up... what am i doing wrong?

  3. GBA Editor
    Martin Holladay | | #3

    The GBA computer generates automatic e-mail notifications whenever an answer is posted to your thread.

    The computer uses the return-address "[email protected]." But that computer-generated e-mail doesn't mean that Dan wrote an answer to your question. In this case, the answer came from me.

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