Replies

1. 
   hasbeen | May 02, 2003 03:02am | #1

   Yes. Unless maybe you are building in true desert. 6 mil is typical.

   Any jackass can kick down a barn, but it takes a carpenter to build one.

2. 
   mosseater | May 02, 2003 08:44am | #2

   Tu-Tuff by Stocote is a great product. Blows clear poly out of the water.

1. 
   DaveRicheson | May 02, 2003 03:22pm | #3

   Is that anything like Visqueen?

1. 
   brownbagg | May 02, 2003 03:41pm | #4

   the purpose of plastic is to reduce the migration of moisture. During the placement of concrete sand will suck the moisture out of the mix creation cracks. After placement it will reduce soil moisture fom entering and creation havoc on the flooring trade. plastic cheap, just tape the seams real good and do not let the concrete crew punch holes.

1. 
   joeh | May 02, 2003 05:39pm | #6

   Johnnie, where you been? How's the house coming? Done and working on the next one?Joe H

1. 
   brownbagg | May 02, 2003 07:16pm | #7

   building garage now

2. 
   mosseater | May 05, 2003 08:01pm | #9

   Sorry, not familiar with Visqueen. Tu-Tuff perm rate is virtally zero and highly puncture resistant. The only problem I`ve had with it is after long-term exposure to the elements (8months-1yr.), it has a tendancy to crack or tear where it has been severely wrinkled while being rolled onto the cardboard tube that it is shipped on.

3. 
   Catskinner | May 02, 2003 03:54pm | #5

   Take note of what Johnnie (BrownBagg) is saying. Underslab vapor barriers have become controversial from the concrete guy's point of view. Depending upon the climate, they can wreak havoc with your cure rate in the slab.

   If you need a vapor barrier, it is usually best to cover it with a few inches of sand. This will help keep the slab from curling and cracking as bad. If you use sand, use rebar chairs with flat plates on the bottom "sand chairs" and life will be a whole lot easier.

   DRC

1. 
   TonySq | May 03, 2003 11:25pm | #8

   We're building on Cape Cod and we have pure sand right down to the water table.  It doesn't sound as if I need a vapor barrier if I need to put sand on top of it?

1. 
   BillHartmann | May 06, 2003 12:54am | #10

   No, you need the vapor barrier.

   And checkout http://www.buildingscience.com

   They do not like the idea of using sand above the plastic at all.