Properly installed split face stone can take your wall from bland to grand. While previously identified as hand or machine-split natural stone, newer brands of split face stone, says Black and Decker's "Complete Guide to Masonry and Stonework," include the entire family of natural and cultured veneer stone. The primary characteristic that gives split face stone its beauty is its exposed edge or face that carries a naturally broken or split appearance. Its attraction to builders and homeowners alike is its ease of application and its universal appeal in both interior and exterior applications.
Analyse the surface of the subject wall and determine if it is an existing stone, mortar, concrete or brick surface, requiring no preparation. If it is not one of these materials, its surface must be prepared (see Steps 2 through 4).
Apply a vapour barrier to exterior walls. If the application is on an exterior wall, staple a standard vapour barrier in sheets cut to fit and overlap all edges 6 inches. Seal all edges and overlaps with all-weather repair tape.
Attach metal lath. Nail strips of 18-gauge metal lath on 6-inch centres. Nail tightly with 1 1/2-inch masonry nails.
Apply mortar scratch coat. Beginning at the top of the wall, trowel 1/2 inch of rich mortar onto the entire surface of the lath wall. Allow the material to partial-dry for 4 hours and then, using a scraper or scrap lath, scratch horizontal support lines 1/8 inch deep, 2 inches apart across the entire wall.
Determine the visual effect you wish to achieve. Stand back and examine the overall location of the wall and decide on its intended function and visual effect -- naturally blended, dramatic or colour-contrast. Select the split face stone pattern, object size and colour that best fits the look you seek to create.
Preset the stone segments. Arrange stones in 25-square-foot sections on the driveway or another large area, alternating size, thickness and colour to achieve a blended look. Repeat the process until you have defined the entire wall pattern.
Size and cut the stones. Using a mortar hammer or stone chisel, trim the stones to produce a closely fitting pattern. This is best achieved by holding the subject stone in one hand and chipping 1/8-inch pieces of stone away -- back and forth across the stone -- until the desired size takes shape.
Stack the stones in reverse order, ending with the first stone for the upper right position on the top of the stack. Place the stacks near the wall.
Determine grout requirement. Grouting split face stone walls is optional and almost totally aesthetic. If your design look calls for grout, decide on a complementary or contrasting colour scheme to acquire.
Mix the mortar. Mix 2 parts sand and 1 part Portland cement in a mortar trough and add water to a creamy consistency. Mix for at least 5 minutes.
Lightly moisten a 25-square-foot section of the wall using a masonry brush. It should be just enough to prepare the wall for the first prearranged section of stones.
Apply mortar to the wall. Beginning at the top of the wall, or subsequent sections, trowel 1/2 inch of mortar onto the wall. Go over the surface to ensure that it is a consistent thickness.
Install the stones. Dampen the backside of the stones and apply a 1/4-inch coat of mortar. Using both hands, press the stones in place with a wiggle motion to marry the mortar surfaces. Wipe the excess mortar from the gaps around the stone, being careful to minimise getting mortar on the outside surface of the stone.
Grout the stones if you have chosen to use grout on your wall. Fill your grout bag two thirds full of grout. Beginning at the top of the wall, apply the grout in sections. Allow the grout to set for one hour and tool the material to the desired thickness.
Do not wipe wet mortar from stone faces as this will stain the stone and make cleanup difficult. Always check local building codes for scratch coat drying time and vapour barrier requirements. Take a picture of each of the stone sections before you stack them.
Never work with stones higher than face level. When on scaffolding or a ladder, do not attempt to reach an extended arm to a work space; move the support instead.
Tips and warnings
- Do not wipe wet mortar from stone faces as this will stain the stone and make cleanup difficult.
- Always check local building codes for scratch coat drying time and vapour barrier requirements.
- Take a picture of each of the stone sections before you stack them.
- Never work with stones higher than face level.
- When on scaffolding or a ladder, do not attempt to reach an extended arm to a work space; move the support instead.