- SUBFLOOR PREPARATION:
- All substrates must be clean, dry, structurally sound, properly cured and free of dirt, oil, paint, old adhesive, wax, sealers, curing agents and any material that may inhibit bonding. General scouring with 20 grit or #3 1 / 2 paper will remove most compounds. All loose materials must be vacuumed from the surface after scouring. The subfloor must be flat to a tolerance of 3/16” in a 10’ radius. Hollow spots, popping spots and squeaks are related to unevenness in the subfloor. Grinding concrete floors is preferred over the use of filling compounds. If filling/leveling compounds are used, they must be Portland cement based and have a compressive strength equal to or greater than 3000 psi when cured. Moisture level in concrete subfloor will fluctuate. Any cementitious material used must be rated for the highest moisture content possible. Consult the cementitious material manufacturer’s application directions. Use of product over light weight concrete and all gypsum based materials requires the use of Titebond Concrete Primer or equivalent prior to application of adhesive.
- MOISTURE CONTENT LIMITATIONS:
- Titebond 821-Step may be used as an adhesive and moisture control system for concrete slabs with elevated moisture levels. Calcium chloride or in-situ RH testing is NOT necessary. To ensure a proper bond and full moisture control, it is essential that the concrete be dry to the touch and fully cured before installation. For flooring adhesive only application method, concrete subfloor moisture cannot be greater than 3 lbs./1000 sq.ft./24 hours on a Calcium Chloride Test or greater than a reading of 4.5 on a Tramex Concrete Moisture Encounter or 75% relative humidity per an in-situ probe test.
- INSTALLATION: ONE-STEP ADHESIVE, MOISTURE AND SOUND CONTROL METHOD:
- When using this method, follow all previous instructions for subfloor preparations. Be sure to obtain the correct trowel. Trowel product with the correct trowel and immediately install the wood flooring into the wet adhesive. To reduce slippage, secure the first two starter rows with starting blocks fastened to the substrate or wedges against starting wall. Remaining planks must be placed firmly into adhesive. Planks that are not flat should be weighted for several hours. 100% adhesive coverage, with no voids, is required to qualify for the all-in-one installation warranty. Open time depends on relative humidity and is usually around 90 minutes. Be sure to seat the flooring into the adhesive firmly. Any low or high spots may cause voids in the adhesive and void the warranty.
- INSTALLATION: ADHESIVE ONLY METHOD:
- It is recommended that the adhesive be allowed to flash for 30 minutes prior to installing the wood flooring. To reduce slippage, secure the first row using Titebond Wood Flooring Tape. NOTE: Do not walk on the floor during the installation. You should not work on top of the wood. Normally, ultimate strength will be reached in 24-48 hours. Wait at least 2 days before finishing an unfinished floor. Titebond 821-Step can be used in conjunction with Titebond 531 Plus Moisture Control System for an installation with NO MOISTURE LIMITATIONS.
NOTE:The recommended flash time for Titebond 821-Step is 30 minutes, depending upon subfloor moisture and humidity.
- RE-SEALING AND RE-OPENING PARTIAL PAIL:
- Scrape sides of pail (this will aid in removal of adhesive later). Place plastic trash bag over unused adhesive, working out any air pockets. Replace lid on pail and tightly seal. Upon re-opening pail, remove trash bag. Material should be ready for use.
- GLUING PLYWOOD OVER CONCRETE:
- 1. Use 5/8″ CD Exposure 1 Plywood subfloor panels, 4′ x 8′ sheets; cut sheets into 2′ x 8′ or 4′ x 4′ sections
2. Score the back of the panels half the thickness of the panel on a 12″ x 12″ grid in order to relieve tension in plywood
3. Use a 1/4″ x 1/4″ square-notched trowel to apply adhesive to concrete
4. Lay sections in a staggered joint pattern in the adhesive, with 1/8″ spacing between sheets, and 3/4″ minimum expansion space at walls and all vertical obstructions
5. Add weight as necessary to ensure adhesive remains in contact with plywood as it cures
6. Allow adhesive to dry overnight before proceeding with flooring installation
- As the pre-finished flooring is being installed, immediately wipe any wet adhesive from the flooring, tools and equipment with mineral spirits. Do not allow adhesive to cure on surface of the flooring, tools or equipment. Follow solvent manufacturer’s directions when working with solvents. Cured adhesive will be difficult to remove.
- Titebond 821 Premium may be used for above-, on- and below-grade applications and on all substrates listed in this specification guide. All applications are susceptible to moisture and should be tested for moisture prior to installation in several locations within the installation area.
Acceptable conditions of concrete for above-, on- and below-grade applications are:
- Less than 3 lbs. /1000 sq.ft./24 hours on a Calcium Chloride Test (ASTM F1869)
- Less than a reading of 4.5 on a Tramex Concrete Moisture Encounter
- Relative humidity (RH) of 75% or less when tested with an in situ probe (ASTM F2170)
Acceptable conditions of wood substrates are a moisture reading of less than 12% or be no more than 4% different from the flooring being installed when using a Tramex, Delmhorst or equivalent wood moisture meter. If subfloor moisture conditions do not meet above guidelines at the time of flooring installation, or they could exceed them at any time after installation, then a Titebond moisture control system should be used.
- Do not install solid wood below-grade
- Do not use on concrete with curing agents or sealers (except for recommended Titebond or Franklin products)
- Avoid allowing adhesive to cure on wood flooring surface
- Do not allow foot traffic for 8 hours after installation
- Do not use as a leveler
- Installations in dry climates or over dry subfloors will take longer to cure
- Temperature and humidity will affect the open time and the cure time of the adhesive
CAUTION: Do not sand, scour or abrade any material that is suspected of containing asbestos fibers. Asbestos is known to cause cancer. Federal law requires that asbestos be handled by a licensed and certified hazardous materials contractor.
* The recommended flash time for Titebond 821 Premium Wood Flooring Adhesive is 30 minutes, depending upon subfloor moisture and humidity. Specific questions regarding “flash time” should be directed to Franklin Technical Service at 1.800.347.4583.