Specification

PRODUCT DESCRIPTION
Basic Use: CertainTeed MemBrain Smart Vapor
Retarder is a vapor retarder sheeting intended
for use with unfaced, vapor permeable mass
insulation (fiber glass and mineral wool) in wall
and ceiling cavities.
Benefits: MemBrain Smart Vapor Retarder is
a polyamide film that changes its permeability
with ambient humidity conditions. The product’s
permeance is 1 perm or less when tested in accordance with ASTM E 96, dry cup method, and
increases to greater than 10 perms using the wet cup method. This process allows closed building
envelope systems to increase their drying potential with seasonal climatic changes. With a high
resistance to water vapor in winter, MemBrain reacts to relative humidity by altering pore size,
allowing water vapor to pass through it. When conditions change and relative humidity increases
above 60%, the pores in the material expand and its permeability increases. This transformation
permits drying to occur, in either direction, through the process of vapor diffusion. Thus, its lowered
resistance value supports the drying process, therefore decreasing moisture accumulation within the
construction and potential moisture damage.
OPEN ATTIC APPLICATION
The following thermal performance values are achieved at the thicknesses, weights and coverages
specified when insulation is installed with pneumatic equipment in a horizontal open blow application.
This product can be used in place of traditional vapor retarders with unfaced fiber glass insulation to provide
an insulation system that is ideal in some of the more severe climate condition areas in terms of both
temperature and humidity. In addition, MemBrain may be installed as an interior air barrier system combined
with recommended tapes and sealants.
Composition and Materials: MemBrain Smart Vapor Retarder is formed by blowing a 2-mil thick film
of polyamide (Nylon).
Limitations: MemBrain Smart Vapor Retarder is recommended for use in heating and mixed climates.
The product is not suited for cooling climates with high outdoor humidities. MemBrain is not suitable in
buildings with exceptionally high, constant indoor humidity levels, such as swimming pools and spas.
This product should also not be used with specialty-conditioned spaces with relative humidities
intentionally greater than 50%. Use of MemBrain is not recommended where residential humidification
systems are set at relative humidities greater than 50%. MemBrain’s performance in rooms with short
peaks of high humidity, such as bathrooms and kitchens, will not be affected because of the buffering
action of interior finishes.
Do not use low permeance interior finishes such as vinyl wallpaper or vapor retarding paints with
MemBrain. The drying benefits of MemBrain will diminish with the use of low permeance finishes.
MemBrain has not been tested for use with wet spray insulation systems and is not recommended at
this time. MemBrain should not be used as a vapor barrier between concrete sub floors and flooring
materials, or as a ground cover in basements and crawl spaces. This product is not recommended
for applications having direct or indirect (reflected) ultraviolet light exposure due to solar or electrical
sources. Special care should be taken when working with an open flame. Check local practice and/
or building codes for use of vapor retarders. To avoid danger of suffocation, keep this and all plastic film
away from babies and small children.
Sizes: This product is manufactured in nominal widths to cover interior walls that are 8, 9, 10 and 12
feet high. The material is folded and rolled to create rolls containing 100 linear feet of product. Available
standard sizes are listed in Table 1.
Product Name
MemBrain™, The SMART Vapor
Retarder & Air Barrier Film
Manufacturer CertainTeed Corporation
Address
P.O. Box 860
Valley Forge, PA 19482-0105
Phone [phone]
•
800-233-8990
Fax [phone]
Website www.certainteed.com/membrain
TECHNICAL DATA
Applicable Standards
• ModelBuildingCodes:
– ICC
– National Building code of
Canada 2005 & 2010
Articles 9.25.4.2
Articles 9.25.3
CCMC Evaluation Report #13278-R
•MaterialStandards:
– ASTM C 665
Section 7.4, Water-Vapor
Permeance
– ASTM E 96
Fire Resistance
– ASTM E 84
Surface burning characteristics
 Max.FlameSpreadIndex:20
Max. Smoke Developed
 Index:55
Quality Assurance
CertainTeed was the first fiber glass insulation
manufacturer to have its manufacturing plants,
R&D center and corporate headquarters registered
to ISO 9001-2000 standards..
MemBrain
™
, The SMART Vapor
Retarder & Air Barrier Film
SPOT: PMS 300 & PMS 425
Specification Sheet
PHYSICAL AND CHEMICAL PROPERTIES
PROPERTY TEST METHOD RESULT
Water Vapour
Permeance
(57ng/Pa•s•m
2
)
ASTM E96
Desiccant Method
<1.0 perm
Water Vapour
Permeance
(572ng/Pa•s•m
2
)
ASTM E96
Water Method
>10 perms
Corrosivity ASTM C665
No unusual aspect
of corrosion such as
pitting, cracking
and adhesive
cure inhibition
Fungi Resistance ASTM C1338 No growth