# Vapor Barrier Around Gas Insert



## nick_wa (Feb 16, 2015)

I have a large masonry chimney on the outside of the house and a heatform installed in the basement block wall.  I am finishing the basement and we want to add a gas fireplace insert into the heatform,

The gas insert has clearances of 6" to the sides and 15" to the top.  I am covering the concrete block walls with XPS to provide a moisture barrier and R-5 insulation.  I will build stud wall in front of that and fill with R12 fiberglass.  I can only bring the XPS within the allowable combustible clearances on the top and sides.

I know I can use Roxul to insulate the 6" to the sides and 15" above but how do I provide a vapor barrier here.  The top 15" is basically just the metal heatform so I do not need a vapor barrier here, but the two sides are concrete block.  I feel like Poly could get too warm.

How can I do a vapor barrier within the combustible clearance needed by the gas insert?


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## Heatsource (Feb 17, 2015)

welcome to the forum Nick

good question, we dont really have basements out here so i've never dealt with it..

I'd ask the shop where you are purchasing the insert, let them do some work to earn your sale


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## nick_wa (Feb 19, 2015)

Bump, any ideas?  I am having hte gas line run today then I will fill the vent holes and concrete patch over them.  After that I will need to insulate / vapor barrier so I can start on my walls.


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