Product Brochure

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Please note that wedi product systems might trap rising
moisture during cure time or in general from uninsulated
concrete ground floors not equipped with a vapor barrier.
Concrete subfloors must not be subject to hydrostatic water
pressure. Do not use wedi product where substrate is subject
to excessive moisture and moisture content changes.
 Wood subfloors and structures attached to wooden
subfloors and all wall and bench framing must be
kept dry, and wood moisture content must be
maintained at consistent service and use levels and
must not exceed 15%. Where constant moisture
or vapor is present, ventilation must be installed to
eliminate exposure of the wood structure from below
the wedi product layer.
 Concrete and Cement-based subfloors and structures
must be fully cured (at least 28 days but up to 3
months for new Portland cement-based concrete
or lightweight concrete under normal conditions,
depending on thickness, mix ratio, and ambient
climate). Field verification of full cure (see moisture
level indicators below) is necessary to determine a full
cure. In addition, residual humidity must not exceed
the following value per each floor type when setting
wedi product and/or tile coverings:
 Calcium Sulphate Screeds: 0.5%
 Calcium Sulphate Screeds, heated: 0.3%
 Cement Screeds: 3.5%
 Gypsum based underlayment: 1% (or per
man-ufacturer recommendation)
 Anhydrite Screeds: 0.5%
 Conduct measures with CM device.
 wedi products must be used with suitable tile
adhesive, grout, and tile.
 Do not use wedi products as a wear surface or
without tile or other suitable coverings.
 When adhering wedi product to subfloors or
other horizontal areas such as benches, choose
a cement-based thin-set or epoxy-based thin-set
adhesive designed to work with the substrate and
wedi’s cement-based surface coating. We generally
recommend cement-based thin-sets meeting or
exceeding ANSI 118.4 (Modified Dry Set Cement
Mortar). Ensure that a thin-set mortar coverage of
95% or more is achieved to fully bond and support
the wedi product or the tile. This is especially
important in wet area applications in order to avoid
water moving and accumulating between wedi
and tile. Ensure that the thin-set mortar application
thickness is within the permissible range for these
products and does not exceed a thickness in excess
of 1/4 inch (when compressed). Use a range of
notch trowels to adhere these wedi products:
 wedi Building Panel on floors or solid walls:
min. 1/4 in. x 1/4 in. up to max. 5/16 in. x 5/16
in. square notch trowel and applied to floor
substrate (compressed thin-set thickness 1/8 in.–
5/32 in.). A skim coat of thin-set mortar may be
applied to the wedi Building Panel to improve
the bond.
 wedi Fundo Shower Bases on floors: min. 3/8
in. x 3/8 in. up to max. 1/2 in. x 1/2 in. square
notch trowel and applied to floor substrate
(compressed thin-set thickness 3/16 in.– 1/4 in.).
A skim coat of thin-set mortar must be applied
to the wedi shower base using the flat side of
the trowel to ensure an improved bond.
 wedi Subliner Dry Sheet membranes and sealing
tapes on floors or walls: min. 3/16 in. x 3/16 in.
up to max. 1/4 in. x 1/4 in. square notch trowel
and applied to the substrate (compressed thin-
set thickness 3/32 in.– 5/32 in.)
 Alternatively, different notch trowel types can
be used if the result is compressed thin-set layer
thickness within the recommended range. This may
require applying a notched thin-set layer on both the
substrate and wedi product.
 All thin-set mortar applications over substrate and
wedi product should be flat troweled on surfaces
before combing through the mortar using the
notched side of the trowel.
 Some substrates may require priming to allow
for thin-set mortar adhesion (such as gypsum
underlayment). wedi Building Panels are installed
to wall framing using wedi fasteners, including
washers for safe load distribution. wedi’s coated
coarse-thread screws are suitable for use with wood
framing and framing 20 ga. or lighter. In heavier
metal framing, use wedi self-tapping screws. The
fasteners are applied through wedi Building Panel