PACKAGING and COVERAGE
LimeStrong Sand is packaged in 32 lb. bags—enough to mix with 2 gallons of water in a common 5 gallon bucket to make one batch. Coverage per bag/batch is 80-100 square feet using two coats at 1/4 inch total thickness max.
For each bag of mix, you will need 2 gallons of clean water. To calculate water needed for any amount of dry plaster, use the online WATER CALCULATOR.
Adding color or tint to LimeStrong plaster is a simple process. Any universal colorant will work, especially quality dry-powder pigments like those selected for the LimeStrong Color System. If using the LimeStrong Color System, use the online COLOR CALCULATORS to formulate shades and blends for any amount of dry plaster. As always, add the liquid tint or pigment powder to the batch-measured mix water before adding dry plaster mix.
LimeStrong Sand finish plaster can be applied successfully on non-porous and porous substrates. Non-porous substrates include new and painted drywall, and concrete. Porous substrates include stucco, lime and gypsum plaster. Cinder or concrete block construction will need a filling/leveling base coat of a coarser, thicker material like LimeStrong BASE before applying SAND.
NEW DRYWALL: Before applying SAND, drywall should be finished and sanded to Level 3 with all joints coated flat. Screw holes should be filled and outside corners beaded and filled. Hollow joints, screw heads, and corner bead may show up in the final plaster finish.
PAINTED DRYWALL: In most cases, SAND can be applied directly to previously painted drywall. Repair dents, nail pops, holes, etc. before application.
STUCCO, GYPSUM PLASTER, LIME PLASTER: Porous substrates that are unpainted and physically and mechanically sound are ready for SAND application as-is. Substrate should be clean and dust free. If excessive suction is present, the substrate will need to be primed before application.
New drywall surfaces must be primed prior to application of LimeStrong. We recommend priming drywall surface with a high quality latex based or PVA primer gaged with Dimension Grit, a fine pumice aggregate. Dimension Grit provides mechanical key for the plaster to adhere to the drywall and allows the lime plaster to spread evenly over the primed surface without sliding. Apply primer with roller. Primer should dry for 12 hours before applying first coat of SAND.
MIXING LIMESTRONG SAND
WATER: Add 2 gallons of water (8 liters) to clean 5 gallon bucket. If using a tint to color SAND, remove 1 quart of water from the bucket and set aside for later use.
LIQUID COLORANT: Do not shake tint container. Pour entire contents of the liquid pigment container into the mix water. Rinse the container twice with the saved water and use a small paint brush to clean all of the tint pigment from the sides and bottom of the container to ensure all the tint is used. With all the tint in the water, mix with the drill as the tint may have settled to the bottom.
POWDERED COLORANT: Add weighed/measured pigment powder to pre-measured mix water while agitating water slowly to avoid settling. Tap to knock free any pigment clinging to sides of container. Mix at high speed with drill-attached paddle (30 seconds to one minute), making sure colorant is completely dissolved in the water. Add plaster immediately.
Download the PDF of our LIMESTRONG PLASTER MIXING GUIDE for more detailed instructions on mixing colorants into LimeStrong plasters.
PLASTER POWDER: 1—Pour one-third to half the bag of SAND plaster into the water. Mix well with the drill for 2 minutes. Scrape any unmixed plaster that sticks to the side of the bucket into the wet mix. 2—Repeat Step 1 until all remaining SAND has been added to bucket. Mix thoroughly and scrape sides of bucket often.
APPLYING LIMESTRONG SAND
With a standard hawk and trowel, apply first coat with a thickness of 1/16 or slightly more so the plaster covers the biggest particles (grain height). Apply as evenly as possible avoiding trowel lines and ridges. When the plaster dries about half way, trowel over it again with a clean trowel to even ridges, high points and imperfections. Avoid making it too smooth as it needs a bit of tooth for the next coat to bond to. If the plaster pulls or stretches, spray the trowel or plaster directly with a very small amount of water to lightly lubricate the plaster surface.
The application of the second coat is applied after the first coat is completely dry. For all finishes, apply another coat (grain height) and then double back over the surface with more plaster, working in random directions. This coat is where you can create a troweled texture, if desired.
TROWELED SMOOTH: When the surface has dried slightly, you can come back with a clean trowel and, optionally, a small amount of water to further smooth the surface. (Optional: apply LimeStrong Soap Finish. See below.)
SPONGE FLOAT: With a stucco sponge float or a tile sponge, you can create a sandy, matte finish that typically is more mottled in color. To create this finish, wait until the finish coat is about 50% dry, then using a slightly damp sponge move the plaster around in a swirling pattern.
WOOD FLOAT: A wood float finish is similar to a sponge float but smoother. The texture tends to be from the biggest sand grains dragging under the float to create a texture. The wood float finish is similar to the sponge. Wait until the finish coat is 50% dry and swirl and scour the surface with a damp wood float.
DRAGGED: A dragged finish is created when some type of texture tool is dragged across the surface this is timing-intensive and has to be done evenly at the right time to achieve a good result. In most cases, the dragged pattern is set into the wet plaster and then the surface is smoothed slightly with a trowel to soften the effect.
USE-WINDOW FOR MIXED PLASTER
The lime + pumice formulation of LimeStrong plasters creates a mix that is slightly hydraulic. This hydraulic reaction is strongly affected by temperature. Mixed plaster stored in warm or hot conditions will set faster than if stored in cool, above-freezing conditions. The plaster, once mixed with water, will slowly stiffen and become firm. As a general rule, the mixed plaster will be usable for 7 to 10 days. Within that 7 - 10 day window, remixing may be necessary to return the plaster to an ideal working consistency.
Store mixed LimeStrong in an airtight container and keep from freezing or extreme heat.
LIMESTRONG SOAP FINISH
A LimeStrong Soap Finish (optional) will give the plaster a silky feeling and will increase stain resistance and wipe-ability to the plaster. The soap finish is applied after the plaster finish coat has completely dried.
LimeStrong Soap Finish comes concentrated and needs to be diluted 8 parts water to 1 part soap. For a full bucket of diluted SOAP, mix the one-half gallon concentrate with 4 gallons of water.
Apply the soap with a new or clean roller. Use a roller screen in a bucket, dip the roller in the bucket, and roll off any excess with the screen. Start at the bottom of the wall, roll the soap on in random directions, taking care to avoid linear stroke patterns and drips. Apply two coats of soap, one immediately after the other. See Soap Finish Instructions for more complete details on the process.