Green Board For Bathroom Walls Do I Need Vapor Barrier

When a vapor barrier is on the side of a wall where the dry air is i e outside in winter or inside in summer moisture problems can occur.

Green board for bathroom walls do i need vapor barrier.

Greenboard drywall isn t water proof it simply resists moisture better than the standard gypsum board that s on most walls in homes around the united states. I think it is a wise choice for mold protection. I would suspect that a water resistant wall board green board was to be used and the international codes as well as the old ubc do not allow this to be installed over a vapor retarder 2006 ibc irc and 2009 ibc editions or a class i or ii vapor retarder 2009 irc in tub or shower compartments. You can t put a vapour barrier behind green board because it creates a double moisture barrier especially where the boards are getting tiled over.

You shouldn t be putting safe and sound insulation in there either because that might screw up the moisture air flow behind the boards. Ceiling fans are a great help but are typically not left on long enough 45 mins after a shower. Do you need a moisture barrier when building a shower enclosure. A vapor barrier s job is to keep water vapor in humid air from diffusing through one side of a wall and finding a cool surface inside the wall.

You don t need to put a vapor barrier in the ceiling of the bathroom. A vapor retarder is a material used to prevent water vapor from diffusing into the wall ceiling or floor. I use mr board in any rooms with water fixtures walls ceilings such as kitchen bath laundry. If you are not sure if you need insulation in your walls follow along with this flow chart.

The home builder wants to demolish that wall make it plumb and apply green board against the wood wall then apply cement board over the green board. When you get. Because of moisture bathrooms are some of the primary areas of your home at risk of mold and mildew development. After the insulation is in place you will want to add a vapor retarder sometimes called a vapor barrier if you need one.

Not every wall does. It is important to make sure that a proper vapor barrier or vapor retarder is installed on the walls in your bathroom whenever you re building or remodeling. I had suggested to the home builder that i would rather put 15 lbs felt over the wood wall then put the cement board over the felt but the home builder said that they would not do that.