SKIMFLOW® LCB is a gypsum based self-leveling underlayment designed for use directly over wood. The product is reinforced with fibers for superior performance over flexible substrates. SKIMFLOW LCB may be poured directly over wood without mechanical reinforcement to provide a quick dry, smooth surface for approved floor coverings.
Features and Benefits
- Outstanding flexural strength
- Suitable for plywood and gypsum subfloors
- Durable high strength specialty cement
- Outstanding heal
- Non-alkaline – adhesive friendly
- Withstands construction/renovation traffic
- 50 lb. (22.5 kg.) Bag Kraft paper, double wall bag
- 5 gallon pail (19 L) with pour spout
- 1 gallon bottle (3.8 L) with pour spout
To maintain warranty, subfloor must be properly primed. Use approved primer on all surfaces. All supporting surfaces shall be structurally sound, solid, free of movement and well bonded. They shall be free of dust, oil, grease, tar or other contaminants that may act as a bond breaker. Do not apply over single stripwood floors or over wood subfloors prone to excessive swelling (not exterior glue or “underlayment” grade). Porous substrates will need to be sealed prior to applying primer and may require more than one coat. Make sure that the substrate is properly primed/sealed before continuing.
Remove all foreign matter by mechanical means. Floor must be free of efflorescence and excess moisture. To check moisture, test with a calcium chloride test (ASTM F1869), or relative humidity (insitu probe) test (ASTM F2170). To correct moisture problems see DEPENDABLE’s moisture protection products.
Subsurface must be watertight as SKIMFLOW LCB is extremely flowable. Make sure any holes, cracks, etc. that would permit material through to a lower level are patched or filled with DEPENDABLE WHITE SKIMCOAT prior to priming.
Application over textured surfaces generally gives best bond. Extremely smooth, glazed tile must be abraded. Steel trowelled concrete can be scarified or bead blasted to give a suitable surface. A test patch for adhesion should be performed if the installer is in doubt. Before starting installation, establish the level around the area to be filled with a transit, level or laser device. Mark a “do not exceed” level around room or area perimeter by snapping a line or marking a minimum level by setting coated nails or screws just below the level to be achieved.
Clean and sweep the floor free from dust and contaminants prior to installation. Pre-wet the floor prior to priming; for particularly porous floors mix PRIMER SL 1-to-1 with water as an initial seal. Once the floor is prepared for primer, prime the floor with PRIMER SL full strength, and wait until dry or tacky.
Clean and sweep the floor free from dust and contaminants prior to installation. Gypsum concrete must be sealed prior to installing SKIMFLOW LCB. Dependable’s GSL® ACRYLIC SEALER or ACRYLIC EMBOSSING ADDITIVE may be used to seal the floor. After cleaning, mix your sealer 4-to-1 with water and apply a first coat onto the gypsum concrete. After first coat of sealer is dry (minimum 1-4 hours), apply second coat of sealer and allow to dry. Once sealer is completely dry, prime the floor with either ACRYLIC EMBOSSING ADDITIVE or PRIMER SL full strength.
SKIMFLOW LCB can be poured directly over old adhesive residue. Dependable recommends the installer mechanically remove as much of the old adhesive as possible. Once the residue is removed prime the floor with ACRYLIC EMBOSSING ADDITIVE full strength, and the floor is ready for the pour. If the old adhesive residue is Cutback adhesive, Dependable recommends the installer encapsulates the floor with two coats Dependable’s CUTDOWN II. Consult Dependable for technical data sheet for details.
Use a long handled roller, soft bristle broom or paint brush to apply DEPENDABLE PRIMER SL. Do not cover until very tacky or dry (about 1 hour). Refer to Dependable’s Primer Tech Bulletin P-1.
Mix 1 bag SKIMFLOW LCB into 5 quarts (4.75 liters) cool clean water. (10 lbs. to 1 qt. water or 5kg. to 1 liter water). SKIMFLOW LCB can be mixed in large quantity in mortar mixers or special pumps or in smaller quantities (up to 2 bags) in a 20-40 gallon container. Use only a very clean mixing container that does not contaminate SKIMFLOW LCB with other material. Pre-dampen container to provide proper first mix. Pour in proper amount of water and then add powder while mixing. Do not over-water. If a problem is encountered while mixing and you are not getting a lump and powder free mix, try starting with 2/3 of proper water, adding powder until just wetted, then adding remainder of water and thoroughly mix at 850-1200 RPM. Mix for at least 2 minutes, but no longer than 3 minutes to a homogenous lump-free mixture. Do not shake.
Pump or pour contents onto floor. Because SKIMFLOW LCB is very flowable, allow it to build in one area until it reaches at least desired depth and maintains that depth even as material flows away. Begin at a corner of room or at a deep part of fill. Plan the pour before starting. Either work back and forth along a line of the room or from the center of the fill outwards in all directions to keep pouring against the freshest material possible. Lightly work the transition points between pours and material over or under desired depth with a screed, spreader, lightweight float or straightedge to the desired depth. Material should remain highly flowable for 20 minutes and can be walked in for over 45 minutes at normal temperatures. Any imperfection can be smoothed by surface trowelling or drawing a straightedge or smoother over the surface. As material gets stiffer and begins to gel, it may be smoothed or trowelled to a featheredge. Once material begins to gel, stay off the area for about 1.5-2 hours, after which floor should bear foot traffic. In very hot or windy conditions, protect from wind and mist fog floor. Direct sunlight, heat and wind can cause rapid drying of the product which may reduce working time. To avoid rapid drying, provide protection against these elements. Let material continue to dry before covering until evaporative moisture lessens. Moisture level may be checked by a surface moisture meter, a plastic film taped to the floor, or a plastic bucket left on the floor and the area carefully observed for residual surface moisture upon removal. In thin 1/4” applications, SKIMFLOW LCB may be covered in 4-24 hours depending on drying conditions (temperature, humidity, thickness) and requirements of adhesive and floor covering. For impervious coverings (vinyl, laminate, etc.) be sure SKIMFLOW LCB is thoroughly dry (at least 16-24 hours). Pours deeper than 3/8” require longer time or forced drying.
Multiple lifts: SKIMFLOW LCB may be placed in multiple lifts or layers. Allow the previous layer to harden and dry until there is no discernible evaporation. Once dry, prime again with Primer SL and apply the next SKIMFLOW LCB layer. Remember thicker areas of product take longer to dry.
NOTE: Temperature and humidity levels affect the drying characteristics of SKIMFLOW LCB.
LIMITATIONS - For Interior use only - Do not use...
• Where hydrostatic pressure (water) is present or moisture emissions exceeds level permitted for installed floor covering.
• Where surface or ambient temperature falls to or below 45°F 72 hours before or after installation.
• Over presswood, particle board, masonite, chipboard, single stripwood floors, luaun or similar dimensionally unstable materials susceptible to moving or swelling.
• As a trowelled patch or at less than natural minimum flow thickness.
• Exterior, exposed applications or as a wear surface.