LATICRETE® 18
Sound Control Underlayment
Data Sheet 253.0
1. PRODUCT NAME
Approximate Coverage
LATICRETE® 18 Sound Control Underlayment
Standard Configuration – 150ft² (13.5m2 ) per unit
Plus Configuration - 100ft² (9m2) roll per unit
2. MANUFACTURER
LATICRETE International, Inc.
1 LATICRETE Park North
Bethany, CT 06524-3423 USA
Telephone:
(203) 393-0010 ext. 235
Toll Free:
(800) 243-4788 ext. 235
FAX:
(203) 393-1684
Shelf Life
Factory sealed containers of this product are guaranteed to be of
first quality for one (1) year if stored off the ground in a dry area.
Limitations

3. PRODUCT DESCRIPTION
LATICRETE 18 Sound Control Underlayment is a high
performance acoustical underlayment system that muffles impact
noises and reduces sound transmission through ceramic tile,
stone and other hard surfacing materials. LATICRETE 18 Sound
Control Underlayment consists of two (2) factory-proportioned
components which are mixed on site to form a sound dampening
mortar. Non-toxic and non-flammable, this compound is easily
applied by trowel and cures rapidly. For new construction and remodeling work, LATICRETE 18 Sound Control Underlayment
combines low installed weight with minimal “above substrate”
thickness. At the same time, high compressive strength provides
the load bearing support required by ceramic tile and other hard,
rigid flooring. Sound Control Underlayment is available in two
configurations: “Standard” configuration, is used when an
acoustical suspended ceiling is present or “Plus” configuration
(with or without ceiling) which incorporates a thin, fiberous sound
control mat. Established by independent laboratory testing to be
an effective sound attenuating barrier, LATICRETE 18 Sound
Control Underlayment is job proven and time tested as a practical
and economical solution to the problem of unwanted noise.
Adhesives/mastics, mortars and grouts for ceramic tile,
pavers, brick and stone are not replacements for waterproof
membranes. When a waterproof membrane is required, use
a LATICRETE Waterproof Membrane (see Section 10 Filing
Systems).
Note: Before installing wood flooring or other moisture sensitive flooring
materials over this product, consult manufacturer of flooring material for
recommendations on substrate moisture content. Allow LATICRETE 18
Sound Control Underlayment to dry in accordance with those
recommendations.
Cautions




During cold weather, protect finished work from traffic until
fully cured.
Contains Portland cement and silica sand. May irritate eyes
and skin. Avoid contact with eyes or prolonged contact with
skin. In case of contact, flush thoroughly with water.
Do not take internally. Silica sand may cause cancer or
serious lung problems. Avoid breathing dust. Wear a
respirator in dusty areas.
Keep out of reach of children.
4. TECHNICAL DATA
Applicable Standard
Uses
Designed specifically for use under ceramic tile, natural stone,
brick pavers, indoor/outdoor carpet, resilient flooring and other
decorative floor coverings. Suitable for interior applications over
structurally sound, clean, concrete. May also be installed over
clean, well-bonded asphalt tile, vinyl tile or resilient flooring.
Ideal for: Vestibules, Bathrooms, Kitchens, Dining Rooms.
Also ideal in high-rise or commercial construction such as:
Apartments, Condominiums, Offices, Hotels, Schools, Hospitals,
and Libraries or wherever else sound control is required. Also
suitable for filling and leveling uneven surfaces as a conventional
underlayment.
Suitable Substrates

Concrete

Cement Mortar Beds

Ceramic Tile and Stones

Cement Backer Board**

Exterior Grade Plywood*
*Interior use, plus configuration only.
**Consult cement backer board manufacturer for specific installation
recommendations and to verify acceptability for exterior use.
Packaging - Factory proportioned kit consisting of:
Standard Configuration/Plus Configuration
5gal. (19L) pail (latex)
220lbs (100kg) drum (powder)
LATICRETE 18 Sound Control Underlayment meets or exceeds
the noise control requirements of:

Building Code of the City of New York (Sec. C26-1208.1).

Building Code of the City of Los Angeles (Sub-Section
91.4903 (h); RGA 1-79).
Performance Properties
Test/Test Method
Results
Compressive Strength
ASTM C-109 (Modified)
Point Loading Strength
> 600 psi (4.2) MPa
Surface Burning Characteristics
ASTM E-84
Flame Spread
Fuel Contribution
Smoke Density
Thermal Conductivity
>5000 psi (35.2) MPa
0
0
0
0.705 BTU in/hr o F ft2
0.10 W/m K
Working Properties
Time to Traffic [70oF (21oC)]
Pot Life
Foot Traffic
Heavy Traffic
Wet Density
4 hours
24 hours
72 hours
56lbs/ft3(900kg/m3)
Data sheets are subject to change without notice, for latest revision check our website.
533578179/RP/02/22/05
SOUND CONTROL PROPERTIES
CONFIGURATION
Floor/
Ceiling
Assemblies
Standard
Thickness
Above
Substrate
(floor covering
not included)
Installed
Weight
(approximate)
0.5 in
(12mm)
nominal
1.7 lbs/ft2
(8.3 kg/m2)
plus ceiling
weight
 52
Plus
(with
suspended
ceiling)
1.0 in
(25mm)
nominal
Plus
(without
suspended
ceiling)
1.0 in (25mm)
nominal
2.7lbs/ft2
(13.2kg/m2)
2.7/bs/ft2
(13.2kg/m2)
Sound
 52
 52
Transmissions
Class (STC)*
ASTM E 492
Impact
 51
 56
 52
Insulation
Class (llC)*
ASTM E 492
Impact Noise
0
+5
+2
Rating (lNR)*
FHA Bulletin
750
Service
Cycles 1-14
Cycles 1-14
Cycles 1-14
ASTM C 627
Rating TCA
Extra Heavy
Extra Heavy
Extra Heavy
Rating**
*These ratings are based on independent laboratory tests.
Copies of complete test report available upon request. (Data
Sheets 253.21/253.22/253.23).
** Tile Council of America Service Rating Categories.
Specifications subject to change without notification. Results shown
are typical but reflect test procedures used. Actual field performance
will depend on installation methods and site conditions.
5. INSTALLATION
Surface Preparation - All surfaces should be between
40oF(4oC) and 90oF(32oC) and structurally sound, clean and free
of all dirt, oil, grease, loose peeling paint, concrete sealers or
curing compounds. Dry, dusty concrete slabs or masonry should
be dampened and excess water swept off. Installation may be
made on a damp surface. Vinyl tile or other resilient flooring
must be firmly bonded. Remove wax or sealers from the surface.
Wipe clean with a wet sponge or towel and allow to dry. Apply a
primer coat of LATICRETE® 18 Sound Control Underlayment
liquid (undiluted) with a brush or roller and allow to dry. Unsound
wood floors will require the use of either 4 mil polyethylene or 15
lb. Builders felt and diamond wire lath securely fastened to the
floor. Refer to LATICRETE Technical Data Sheet 152 (refer to
section 10, Filing Systems).
1. Installer must verify that deflection under all live, dead and
impact loads of interior plywood floors does not exceed industry
standards of L/360 for ceramic tile and brick or L/480 for stone
installations where L=span length;
2. Minimum construction for interior plywood floors:
SUBFLOOR: 5/8” (15mm) thick exterior grade plywood, either
plain with all sheet edges blocked or tongue and groove, over
bridged joints spaced 16” (400 mm) o.c. maximum; fasten
plywood 6” (150mm) o.c. along sheet ends and 8” (200mm) o.c.
along intermediate supports with 8d ring-shank, coated or hot dip
galvanized nails (or screws); allow 1/8” (3mm) between sheet
ends and ¼” (6mm) between sheets edges; all sheet ends must
be supported by a framing member; glue sheets to joints with
construction adhesive; UNDERLAYMENT: 5/8” (15mm) thick
exterior grade plywood fastened 6” (150mm) o.c. along sheet
ends and 8” (200mm) o.c. in the panel field (both directions) with
8d ring-shank, coated or hot dip galvanized nails (or screws);
allow 1/8” (3mm) to ¼” (6mm) between sheets and ¼” (6mm)
between sheet edges and any abutting surfaces; offset
underlayment joints from joints in subfloor and stagger joints
between sheet ends; glue underlayment to subfloor with
construction adhesive. Refer to Technical Data Sheet 152
“Requirements for Direct Bonding of Ceramic or Stone Tiles Over
Wood Floors” for complete details.
3. DO NOT bond to particle board, luan, Masonite® or hardwood
surfaces. For white and light colored marbles use
LATICRETE 220 Marble and Granite Mortar WHITE. For green
and moisture sensitive marbles, use LATAPOXY® 300 Epoxy
Adhesive, refer to Data Sheet 633.0.
Isolate perimeter of installation and any restraining surfaces with
¼” (6mm) thick minimum and 1” (25mm) tall minimum foam
spacing. Expansion joints shall be provided through the tile work
from all construction or expansion joints in substrate. Follow
ANSI Specification AN-3.8 “Requirements for Expansion Joints”
or TCA Detail EJ171 “Expansion Joints”. Do not cover expansion
joints with mortar. If LATICRETE 18 “Plus” configuration is to be
used, install all components of the LATICRETE Sound Control
“Plus” package in accordance with instructions provided. Apply
mat adhesive with a 1/8” x 1/8” (3mm x 3mm) notched trowel. Cut
mat and place into the adhesive while it is wet and tacky. Press
corners and edges of each piece into adhesive to prevent curling.
After placing the mat and before the adhesive dries roll or tamp
the surface to work out air bubbles. Remove wet adhesive with
water. Follow ANSI Specification AN-3.8 “Requirements for
Expansion Joints” or TCA Detail EJ171 “Expansion Joints”. Do
not cover expansion joints with mortar.
Mixing – LATICRETE Sound Control Underlayment Liquid must
be diluted 2.5 parts water to 1 part latex. Stir LATICRETE 18
Sound Control Underlayment thoroughly before use. For a 3.5
gallon (13 ℓ) bucket of powder, mix 1.5
quarts (1.4 ℓ) of LATICRETE 18 Sound Control Underlayment
Liquid with 3.5 quarts (13 ℓ) of water. For a 5 gallon (19 ℓ) bucket
of powder, mix 2 quarts (1.9 ℓ) of LATICRETE 18 Sound Control
Underlayment Liquid with 5 quarts (4.7 ℓ) of water. This is
equivalent to 9 quarts
(8.5 ℓ) of diluted latex for 25 lbs (11.3 kg) of powder Mix by hand
or with slow speed mixer to a smooth lump free easily screeded
mix. For best results, do not mix excessively wet or “soupy”
mixes.
Application - Pour the mix onto the prepared floor, then trowel or
spread to a uniform thickness. Metal screed or gauging strips are
recommended to achieve uniform thickness and maximum
coverage. Patch or fill any voids or uneven areas with the same
mix. Allow to harden. Ceramic tile may then be installed using a
LATICRETE Liquid Latex Fortified or Epoxy Thin-Set mortar.
Follow manufacturer’s recommendations for installing vinyl tile,
linoleum, carpet, wood parquet over concrete. Before installing
wood flooring over LATICRETE 18 Sound Control Underlayment
consult wood flooring manufacturer for recommendations on
substrate moisture content. Do not fasten wood flooring or carpet
tack strips with nails. Use the adhesive methods of installation for
these materials. Construction adhesive can be used to secure the
Data sheets are subject to change without notice, for latest revision check our website.
533578179/RP/02/22/05
carpet tack strips. Allow LATICRETE® 18 Sound Control
Underlayment to dry in accordance with those recommendations.
9. TECHNICAL SERVICES
Technical assistance
6. AVAILABILITY AND COST
Information is available by calling the LATICRETE Technical
Service Hotline (hours 8:00 AM to 5:30 PM EST):
Toll Free:
(800) 243-4788 ext. 235
Telephone:
(203) 393-0015 ext. 235
FAX:
(203) 393-1948
Availability
Technical and safety literature
Cleaning - Clean tools and tile work with water while mortar is
fresh.
LATAPOXY®
LATICRETE and
materials are available worldwide.
For distributor information, call:
Toll Free:
(800) 243-4788
Telephone:
(203) 393-0015
For on-line distributor information, visit LATICRETE at
www.LATICRETE.com
Cost - Contact a LATICRETE Distributor in your area.
7. WARRANTY

To acquire technical and safety literature, please visit our
website at www.LATICRETE.com.
10. FILING SYSTEM
Additional product information is available on our website at
www.LATICRETE.com. The following is a list of related
documents:
DS 236.0: LATICRETE 9235 Waterproofing Membrane
DS 230.13: LATICRETE Product Warranty
DS 230.12: LATICRETE 10 Year System Warranty
LATICRETE International, Inc. warrants that LATICRETE 18
Sound Control Underlayment is free from manufacturing defects
and will not break down, deteriorate or disintegrate under normal
usage for a period of one (1) year from date of purchase subject
to her terms and conditions stated in Data Sheets 230.13
LATICRETE Product Warranty (see 10. FILING SYSTEM).
In addition, when used as a component of a LATICRETE System
Installation, LATICRETE 18 Sound Control Underlayment, is
warranted for a period of ten (10) years from date of purchase
subject to the terms and conditions stated in Data Sheet 230.12
LATICRETE System Warranty (see 10. FILING SYSTEM).
8. MAINTENANCE
LATICRETE and LATAPOXY grouts require routine cleaning with
a neutral pH soap and water. All other LATICRETE and
LATAPOXY materials require no maintenance but installation
performance and durability may depend on properly maintaining
products supplied by other manufacturers.
Data sheets are subject to change without notice, for latest revision check our website.
533578179/RP/02/22/05