This article walks through how to install Earthaus Stone Finish, from substrate preparation through mixing, application, and sealing. It is a summary of the official Earthaus Stone Finish Installation Guide, adapted for clarity and ease of reference. To view the full document, see the Earthaus Stone Finish Application Guide (PDF).

What Is Stone Finish?

Earthaus Stone Finish is a medium-textured interior lime plaster.
Sealed with Olive Oil Soap for light sheen and increased wipeability.
Not suitable for showers or wet areas.
Can also serve as the base coat for the Earthaus Marble Finish.
Final finish depends on installer technique and owner maintenance.

Materials Summary

Total thickness: 1/16"
Two coats of Stone Plaster, each 1/32"
Mineral Pigment: One Pigment Pack per bag
Soap Sealer: One coat minimum, diluted
Primer: Required (with Earthaus Primer Grit additive)

Properties

Made from US-quarried, sustainable lime, pumice, mineral pigments, and plant-based binder
100% natural, zero VOC, no chemical additives
Breathable, mold and mildew resistant
Cures by absorbing CO₂ and re-carbonating into limestone
Excellent workability and adhesion

Where Stone Finish Can Be Used

Suitable For:

Interior vertical surfaces
Accent walls, feature walls
Base layer for Earthaus Marble Finish

Not Suitable For:

Showers or wet-area applications
Exterior application

Substrate Preparation

Approved Substrates:

Level-4 finished drywall
Previously painted drywall (must be clean and dry)
Plywood, with extra preparation (see below)
Sample boards: sheetrock, MDF, tile backer board, ceramic bisque tiles

Plywood Requires Extra Preparation. Plywood can be used, but it is flexible and resin-rich, so it needs additional prep to prevent joint cracking and tannin bleed-through: reinforce all joints with fiberglass mesh tape in quick-set drywall compound and sand flush, then apply two coats of a water-based stain-blocking primer with Earthaus Primer Grit mixed into the second coat. See the article "Can I Apply Earthaus Plaster to Plywood?" for the full method.

Not Approved:

Particleboard (risk of tannin bleed-through)
Oily, waxed, or solvent-treated wood surfaces

Primer Instructions:

Use zero-to-low VOC primer.
Add 1 cup of Earthaus Primer Grit per gallon of primer.
Mix with drill and paddle for 30 seconds.
Apply 1 even coat with brush or roller.
Allow to dry fully before plastering.

Application Sequence

Substrate Preparation
Stone Plaster Base Coat (1/32")
Stone Plaster Finish Coat (1/32")
Olive Oil Soap Sealer Application

Mixing Instructions — Stone Plaster

Add 9 quarts (2.4 gal) water to 5-gallon bucket.
Add full Pigment Pack and mix vigorously.
Strain pigmented water through 5-gal mesh strainer.
Add Stone Plaster in thirds, mixing between additions.
Final mix time: 3 minutes minimum at high RPM.
Adjust water slightly if needed; aim for thick milkshake consistency.

Coat Details

Base Coat:

Apply 1/32" coat with trowel (credit card thickness).
When ~60% dry, use clean trowel to smooth ridges.
Allow to dry fully before finish coat.

Finish Coat:

Apply "tight coat" slightly thicker than largest aggregate grain.
When semi-dry, apply second tight coat (double back).
Burnish with clean trowel as surface becomes firm.
Color will lighten significantly once fully dry.

Sealing Process — Olive Oil Soap Sealer (Required)

Apply when plaster is completely dry (minimum 12 hours).
Dilution: 1 part Olive Oil Soap : 8 parts warm water.
Mix thoroughly.
Apply liberally using brush or small roller, starting from bottom.
Avoid drips/runs; wipe excess with clean cloth.
Additional coats optional for more sheen/protection.

Tips & Common Issues

Even base coats: Prevent high spots to avoid color inconsistency.
Do not overapply: Thick coats increase risk of cracking and uneven color.
Burnishing pressure: Excessive pressure can bruise surface and darken color.
Ambient conditions: Drying time and sheen can vary with temp/humidity.
Color shifts: Final color appears lighter after drying.

Storage & Disposal

Mixed Stone Plaster: up to 14 days (covered, room temp); remix thoroughly before reuse.
Disposal: Let unused plaster dry in container; once dry, dispose in trash.

Tools List

Category	Tools Needed
Substrate Prep	Drill, small mixing paddle, roller or brush
Mixing	1200 RPM drill, egg-beater paddle, mesh strainer
Application	Hawk, trowel, scraping knife
Sealing	1-gallon bucket, brush or small roller

Project Consultation

Earthaus offers technical consultation with experts for project-specific questions.

Still Have Questions? Email [email protected] or text 1-800-917-2414.

Stone Finish — Installation Guide