Product Discription
Unlike conventional non-adhering membranes, which
are vulnerable to water ingress tracking between the
unbonded membrane and structure, the unique Preprufe
bond to concrete prevents ingress or migration of water
around the structure.
The Preprufe R System includes:
- Preprufe 300Rheavy-duty grade for use below
slabs and on rafts (i.e. mud slabs). Designed to accept
the placing of heavy reinforcement using conventional
concrete spacers.
- Preprufe Tape LTfor covering cut edges, roll
ends, penetrations and detailing (temperatures
between 25°F (-4°C) and 86°F (+30°C)).
- Preprufe Tape HCas above for use in Hot
Climates (minimum 50°F (10°C)).
- Bituthene Liquid Membranefor sealing around
penetrations, etc.
- Adcor™ ESwaterstop for joints in concrete walls
and floors
- Preprufe Tieback Coverspreformed cover for soil
retention wall tieback heads
- Preprufe Preformed Cornerspreformed inside
and outside corners
Preprufe 300R & 160R membranes are applied either
horizontally to smooth prepared concrete, carton forms
or well rolled and compacted earth or crushed stone
substrate; or vertically to permanent formwork or adjoining
structures. Concrete is then cast directly against the
adhesive side of the membranes. The specially developed
Preprufe adhesive layers work together to form a
continuous and integral seal to the structure.
Preprufe can be returned up the inside face of slab formwork
but is not recommended for conventional
twin-sided formwork on walls, etc. Use Bituthene selfadhesive
membrane or Procor fluid applied membrane
to walls after removal of formwork for a fully bonded
system to all structural surfaces.
Advantages
Forms a unique continuous adhesive bond to
concrete poured against it prevents water migration
and makes it unaffected by ground settlement
beneath slabs
Fully adhered watertight laps and detailing
Provides a barrier to water, moisture and gas
physically isolates the structure from the surrounding
ground
BBA Certified for basement Grades 2, 3, & 4 to
BS 8102:1990
Zero permeance to moisture
Solar reflective reduced temperature gain
Simple and quick to install requiring no priming
or fillets
Can be applied to permanent formwork allows
maximum use of confined sites
Self protecting can be trafficked immediately after
application and ready for immediate placing of reinforcement
Unaffected by wet conditions cannot activate
prematurely
Inherently waterproof, non-reactive system:
- not reliant on confining pressures or hydration
- unaffected by freeze/thaw, wet/dry cycling
Chemical resistant effective in most types of soils
and waters, protects structure from salt or sulphate
attack
Installation
The most current application instructions, detail
drawings and technical letters can be viewed at
graceconstruction.com. For other technical information
contact your local Grace representative.
Preprufe 300R & 160R membranes are supplied in
rolls 4 ft (1.2 m) wide, with a selvedge on one side to
provide self-adhered laps for continuity between rolls.
The rolls of Preprufe Membrane and Preprufe Tape are
interwound with a disposable plastic release liner
which must be removed before placing reinforcement
and concrete.
Substrate Preparation
All surfaces—It is essential to create a sound and solid
substrate to eliminate movement during the concrete
pour. Substrates must be regular and smooth with no
gaps or voids greater than 0.5 in. (12 mm). Grout
around all penetrations such as utility conduits, etc. for
stability (see Figure 1).
Horizontal—The substrate must be free of loose
aggregate and sharp protrusions. Avoid curved or
rounded substrates. When installing over earth or
crushed stone, ensure substrate is well compacted to
avoid displacement of substrate due to traffic or
concrete pour. The surface does not need to be dry, but
standing water must be removed.
Vertical—Use concrete, plywood, insulation or other
approved facing to sheet piling to provide support to
the membrane. Board systems such as timber lagging
must be close butted to provide support and not more
than 0.5 in. (12 mm) out of alignment.
Membrane Installation
Preprufe can be applied at temperatures of 25°F (-4°C)
or above. When installing Preprufe in cold or marginal
weather conditions 55°F (< 13°C) the use of Preprufe
Tape LT is recommended at all laps and detailing.
Preprufe Tape LT should be applied to clean, dry
surfaces and the release liner must be removed immediately
after application. Alternatively, Preprufe Low
Temperature (LT) is available for low temperature
condition applications. Refer to Preprufe LT data sheet
for more information.
Horizontal substratesPlace the membrane HDPE
film side to the substrate with the clear plastic release
liner facing towards the concrete pour. End laps should
be staggered to avoid a build up of layers. Leave
plastic release liner in position until overlap procedure
is completed (see Figure 2).
Accurately position succeeding sheets to overlap the
previous sheet 3 in. (75 mm) along the marked
selvedge. Ensure the underside of the succeeding sheet
is clean, dry and free from contamination before
attempting to overlap. Peel back the plastic release liner
from between the overlaps as the two layers are bonded
together. Ensure a continuous bond is achieved without
creases and roll firmly with a heavy roller. Completely
remove the plastic liner to expose the protective coating.
Any initial tack will quickly disappear.
Refer to Grace Tech Letter 15 for information on
suitable rebar chairs for Preprufe.
Vertical substratesMechanically fasten the
membrane vertically using fasteners appropriate to the
substrate with the the clear plastic release liner facing
towards the concrete pour. The membrane may be
installed in any convenient length. Fastening can be
made through the selvedge using a small and low
profile head fastener so that the membrane lays flat and
allows firmly rolled overlaps. Immediately remove the
plastic release liner.
Ensure the underside of the succeeding sheet is clean,
dry and free from contamination before attempting to overlap. Roll firmly to ensure a watertight seal.
Roll ends and cut edgesOverlap all roll ends and cut
edges by a minimum 3 in. (75 mm) and ensure the area
is clean and free from contamination, wiping with a
damp cloth if necessary. Allow to dry and apply
Preprufe Tape LT (or HC in hot climates) centered over
the lap edges and roll firmly (see Figure 3). Immediately
remove printed plastic release liner from the tape.
Details
Refer to Preprufe Field Application Manual, Section V
Application Instructions or visit graceconstruction.com.
This manual gives comprehensive guidance and
standard details.
Membrane Repair
Inspect the membrane before installation of reinforcement
steel, formwork and final placement of concrete.
The membrane can be easily cleaned by power washing
if required. Repair damage by wiping the area with a
damp cloth to ensure the area is clean and free from
dust, and allow to dry. Repair small punctures (0.5 in.
(12 mm) or less) and slices by applying Preprufe Tape
centered over the damaged area and roll firmly. Remove
the release liner from the tape. Repair holes and large
punctures by applying a patch of Preprufe membrane,
which extends 6 in. (150 mm) beyond the damaged
area. Seal all edges of the patch with Preprufe Tape,
remove the release liner from the tape and roll firmly.
Any areas of damaged adhesive should be covered with
Preprufe Tape. Remove printed plastic release liner
from tape. Where exposed selvedge has lost adhesion or
laps have not been sealed, ensure the area is clean and
dry and cover with fresh Preprufe Tape, rolling firmly.
Alternatively, use a hot air gun or similar to activate
adhesive and firmly roll lap to achieve continuity.
Pouring of Concrete
Ensure the plastic release liner is removed from all
areas of Preprufe membrane and tape.
It is recommended that concrete be poured within
56 days (42 days in hot climates) of application of the
membrane. Following proper ACI guidelines, concrete
must be placed carefully and consolidated properly to
avoid damage to the membrane. Never use a sharp
object to consolidate the concrete.
Removal of Formwork
Preprufe membranes can be applied to removable formwork,
such as slab perimeters, elevator and lift pits, etc.
Once the concrete is poured the formwork must remain
in place until the concrete has gained sufficient
compressive strength to develop the surface bond.
Preprufe membranes are not recommended for conventional
twin-sided wall forming systems.
A minimum concrete compressive strength of 1500 psi
(10 N/mm2) is recommended prior to stripping formwork
supporting Preprufe membranes. Premature
stripping may result in displacement of the membrane
and/or spalling of the concrete.
Refer to Grace Tech Letter 17 for information on
removal of formwork for Preprufe.
Supply
| Thickness |
0.046" (1.2 mm) |
| Roll size |
4' x 98' (392 ft2) |
| weight |
108 lbs (50 kg) |
| Minimum side/end laps |
3” (75 mm) |