Moisture Vapor Treatment

Perdure MVT

Excess moisture in or below the concrete slab is the cause for a large percentage of coating failures on concrete. While moisture in concrete during the application of floor systems is an important criterion, it is not the ultimate cause of failure months or years later. Many resin based flooring systems can tolerate and bond to a concrete slab with relatively high moisture content. It is the flow of moisture or moisture vapor, better described as moisture vapor transmission, which causes most adhesion problems.

Perdure MVT is a two component modified epoxy system designed to seal concrete and reduce moisture vapor transmission prior to applying finished flooring. Perdure MVT has proven to reduce moisture vapor emissions and be resistant to damage from high alkalinity. It is an environmentally friendly material containing no hydrocarbons or other solvents making it zero VOC.

Perdure MVT is designed as a negative side moisture vapor retarder to reduce moisture vapor transmission though concrete.

ADVANTAGES

• Reduce moisture vapor transmission rate through concrete.
• Provides excellent resistance to highly alkaline conditions.
• Gives excellent bond to properly prepared concrete.
• Can be rapidly resurfaced with a variety of finished flooring covering materials

TECHNICAL DATA
Tensile Strength ASTM D-638	10,400psi
Tensile Elongation ASTM D-638	2-4%
Modulus of Elasticity ASTM D-638	2500psi
Bond strength to concrete, ASTM D-4541	400-500psi100% concrete failure
Permeability ASTM E-96	1 coat (10-12mil) – 0.09 Perms2 coats (20mil) –    0.04 Perms
Water vapor transmission grams/hr/m2 ASTM E-96	1 coat – 0.0232 coats – 0.012
Alkali Resistance7 day immersion14 day immersion ASTM D-1308	10% NaOH– unaffected50% NaOH- unaffected10% NaOH- unaffected50% NAOH- unaffected
Hardness Shore DASTM D-2240	85
VOC	Zero
Water absorption ASTM D-570	Zero
Mix ratio	2A : 1B
Pot life	30 minutes
Recoat time minimum maximum	4-6hr 72 hr

NOTE: It is important to understand the difference between moisture vapor transmission and moisture content. You may have low moisture content and have a bond failure at some point in the future due to vapor transmission through the slab. A high moisture content in the slab will usually not cause a problem unless conditions are right to cause movement of that moisture to the surface. So, its moisture transmission to the surface whether it is from high moisture content in the slab or under the slab that causes the problem.

Allowable moisture vapor transmission for düraamen™ flooring systems

The maximum moisture vapor transmission through concrete when tested as per the Calcium Chloride Test, should not exceed 3.0lbs/24hr/1000 sq.ft.