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Thoughts on whether or not I should put insulation and/or vapor barrier inside my interior bathroom wall?

GreyWolf92 | Posted in Energy Efficiency and Durability on

Good morning,

I framed in my bathroom wall after I put my tongue and groove walls up (currently putting the tongue and groove on the bathroom wall).

I wanted to see what you guys think about whether or not I should insulate and/or use a vapor barrier/retarder in this wall?

I think pretty much the only reason I would insulate is if I wanted to keep sound from the bathroom.
It’s important to note, I will have a sliding barn door here, which will never fully block the sound and also an open joist ceiling (with no insulation). So It seems a waste of money to insulate this wall. With that being said, would you reccomend I use a vapor barrier/retarder membrane? Considering the rooms will be pretty much equal temperature I am thinking I will be ok without doing so.

For reference, I am in climate zone 3 Southern California 15 minutes inland of the beach.

I attached some pictures .

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  1. GBA Editor
    Martin Holladay | | #1

    Grey Wolf,
    Does your bathroom have any exterior walls? Insulation is a code requirement, even in California, for all exterior walls and roofs/ceilings.

    If you are just talking about the partitions (rather than exterior walls), most partitions aren't insulated. Including insulation in the partitions will cut down somewhat on noise transmission.

  2. Expert Member

    Grey Wolf,

    Given the other paths for sound to move out of the bathroom, I wouldn't bother insulating. There is no point using a vapour barrier on any interior walls in your tiny home.

    I see you are moving along!

  3. GreyWolf92 | | #3

    Hey Martin,

    Yes, the bathroom has exterior walls. This picture is standing inside the bathroom showing the partition wall.

    Malcolm, yes I am! About 2 weeks away from moving in finally :) And cool, that's what I was thinking because I wouldn't really see a benefit of either in this case. Just seems weird having nothing inside the wall!

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