ESTIMATING A JOB
To determine the amount of stone needed for a project, calculate total square footage of the project area. Measure the linear footage of outside corners to determine the amount of corner pieces required. One linear foot (lf.) of corners covers approximately ¾ (.75) of a square foot of flat area. Subtract square footage of area covered by corner stones to determine the required square footage of flat stone needed. It is a good idea to have extra stone on hand for cutting and trimming.
Our flat stones are sold in increments of 50 square feet per pallet and our corner stones are sold in increments of 5linear feet.
If you have an area that measures 100 inches high by 246 inches long and contains one outside corner that measures 96 linear inches (i.e., 96 inches high in this case), you will calculate the required stone as follows:
Determine your total square footage: 100 in. x 246 in. = 24,600 in2
Divide by 144 in2 / ft2: 24,600 in2 / 144 in2 / ft2 = 170.83 ft2 or 171 ft2 total area
Determine the area covered by corners: 96″ x 0.75 = 72″
Divide by 12″ to convert to feet: 72 / 12 = 6 ft2 covered by corners
Determine square footage of flat stones needed: 171 ft2 – 6 ft2 = 165 ft2
Divide: 165 ft2/ 50 ft2 per pallet= 3.3 pallets of flats needed
Round up: 3.3 pallets rounds up to 4 – 50 ft2 pallets or 200 ft2 of flat stone
Determine linear feet of corner stones needed: 96″ / 12″ per foot = 8 lf. of corners
Divide: 8 lf. / 10 lf. per carton = 0.8 cartons of corner stones needed
Round up to next whole number: 0.8 cartons rounds up to 1 – 10 lf.carton of corners
” Type “S” Masonry Cement (or pre-mixed Stone Veneer Mortar)
” Masonry Sand (or pre-mixed Stone Veneer Mortar)
” Dye Colorant for Masonry Cement (if desired)
” Minimum 2 ½ lb. Galvanized Expanded Metal Lath (for all but unpainted and untreated brick, concrete, or masonry surfaces)
” Galvanized Nails, Galvanized Screws, or Corrosion-Resistant self-tapping pancake-head screws (for installation against metal walls).
” Flashing that meets local building codes
” Weather Resistant Barrier – kraft waterproof building paper or asphalt saturated rag felt (for all but unpainted and untreated brick, concrete, or masonry surfaces)
Petracraft Stone requires no wall ties, footings, or structural support due to its light weight and subsequent minimal shearing force. This coupled with low cost makes our stone economically feasible.
STEP ONE: Prepare the Surface
Petracraft Stone can be easily applied to any structurally sound surface without any wall ties, footings, or structural supports needed. Install the stone directly to the surface of any clean (unsealed, unpainted, or untreated) brick, concrete block, or other masonry surface. Sealed, painted, or treated brick, concrete block, or other masonry surface must have metal lath securely installed prior to stone installation. For all other surfaces, metal lath and building paper must be applied prior to installation.
On metal surfaces, it may be necessary to use a metal lath with a paper backing if there is no way to attach a building paper to wall. Attach the lath with self-tapping screws every 12″. The screws should be a size that allows for at least a 3/8″ penetration into the metal wall surface and has a pancake-style head that will not pull through the metal lath. Apply a ½” to ¾” scratch coat and allow to cure for at least 36 hours before proceeding.
On rigid backwall surfaces, attach a weather-resistant barrier. Attach the lath by nailing or screwing on centers every 6″, hitting studs whenever possible. Always attach lath right side up with small cups pointing upward. In all cases, when attaching lath to an outside corner, a single sheet of lath MUST wrap around the corner at least 6″ on each side. DO NOT butt edges of lath up to an outside corner. This can result in corner stones cracking during freeze / thaw cycles and will void the stone warranty. Overlap all lath joints at least 6″.
On open studs or insulation board (½” or less), it may be necessary to use a metal lath with a paper backing if there is no way to attach a building paper to wall. Attach metal lath to studs using galvanized nails or screws every 4″ on center. Apply a ½” to ¾” scratch coat and allow to cure for at least 36 hours before proceeding.
STEP TWO: Mortar the Stone
Lay out stones randomly near your work area. After choosing a stone, apply a ½” thick layer of masonry cement evenly on back of stone. If installing an EasyFit® style stone, mortar must be tinted to match the stone to facilitate hiding of the joint lines.
Note: use type “S” masonry cement mixed according to the manufacturers instructions.
STEP THREE: Apply the Stone
Stones installed at ground level will most likely stain and discolor over time. To avoid this, install stones a minimum of 4″ above grade if earth or 2″ above pavement or concrete.
Always install corner stones first unless you are installing an EasyFit® style stone. Corner stones have a long and a short leg. These should be alternated in opposite directions. Apply remaining stones by working from the bottom up or top down. Joints between stones should be as uniform as possible.
If installing an EasyFit® style stone, joints should be as tight as possible since these stones are designed to be installed with minimal or no mortar joints. Ensure that EasyFit® style stones are installed level and plumb. The first course of EasyFit® style stone should be applied at the bottom and you should complete each course entirely before proceeding up to the next course. If EasyFit® style stone corner pieces are required for your application, install a corner piece first and then the adjoining flat pieces in each course before installing the next corner piece. Note that corner stones have a long and a short leg. These legs should be alternated in opposite directions with each course. When using an EasyFit® style stone, ensure that vertical joints do not line up from course to course.
Press stone firmly into place with a gentle wiggling motion to promote bonding. The masonry cement on back of stone should squeeze around the stone’s edges. When installed correctly, backing/scratch coat will not be visible. If installing an EasyFit® style stone, strike off excess mortar around the edges of the stone before placing the next stone.
Note: Stones can be shaped with wide-mouth nippers or a hatchet, or cut with a masonry saw. Cut or broken edges should be coated with mortar and installed in such a manner that the edge cannot be easily seen from average eye level. For EasyFit® style stone, place cut edges within a course and only finished edges at exposed areas. Always wear a dust mask and safety glasses when cutting Petracraft Stone.
STEP FOUR: Remove/Dress Excess Masonry Cement/Mortar
Use a grout bag to fill in joints, if required. Be careful not to smear mortar on the stone surface. If mortar does get on the stone surface, it should be removed after the mortar has become crumbly by using a whisk broom or dry bristle brush. DO NOT use water or a wire brush to remove mortar.
When mortar joints are firm, use a wooden or metal striking tool and remove excess mortar. At the same time, firmly press mortar into the joints so edges are thoroughly sealed.
STEP FIVE: Brush Joints
Using a whisk broom, brush mortar joints until smooth and all loose mortar has been brushed away. Brush off any loose mortar on face of stones. NEVER let mortar set overnight before brushing joints. DO NOT treat mortar joints with anything wet and DO NOT use any acid or acid-based products.
STEP SIX: Clean Stone – Completion
Clean any remaining grout/mortar mix off stone with a broom or brush. You may wish to apply a waterproof sealer to the surface of the stone, as sealed surfaces provide ease in cleaning.
Sills are used under windows. Petracraft Stone has sills for use with stone veneer and with brick. Sills are also used as Watertables to provide a transition piece between your stone wainscot and another exterior finish. Install using galvanized metal supporting brackets (a galvanized right angle bracket with a holding capacity 5 lbs./LF minimum (Simpson A-21 Hanger)) fastened with galvanized nails or screws penetrating studs 1″ at a minimum of 16″ on center. Use construction adhesive to bond stone at bracket locations. Caulk and flash as required to ensure that water cannot penetrate the area behind the sill / watertable.
Petracraft Stone can be cleaned using a mixture of granulated soap and water and a soft bristle brush. Rinse with clean water. NEVER use a wire brush, acid, acid-containing products, sandblasting, or pressure washing on your stone.
Never use salt or other de-icers on or near Petracraft Stone. De-icing agents will damage your stone and Petracraft Stone is not warranted against damage caused by these agents. Do not install Petracraft Stone below water level or in an area subject to chlorine or other chemical contact. Never use acid, acid-containing products on your Petracraft Stone. Damage caused by these conditions is not covered under warranty.
Efflorescence is a naturally occurring phenomenon on concrete and masonry products when salt deposits form on the surface as water that has penetrated the stone or wall behind the stone evaporates. Efflorescence may occur on Petracraft Stone. Efflorescence may be removed by scrubbing stone with a soft bristle brush and a solution of 1 part white vinegar to 5 parts water. Rinse thoroughly. NEVER use a wire brush, acid, acid-containing products, sandblasting, or pressure washing on your stone.
Scuff marks on Petracraft Stone may be removed by cleaning your stone as described above. Keep in mind that scuff marks occur on natural stone and can actually enhance the look of your stone installation.
Sealing of Petracraft Stone is not necessary. However, if you choose to seal your stone installation, choose a breathable sealer that is recommend for use on handcrafted stone. Contact the sealer manufacturer to ensure that their product will perform to your requirements. Damage to Petracraft Stone caused by or magnified by the application of a sealer is not covered under warranty.
Petracraft Stone is NOT designed to be installed in a horizontal or face up position. The reason for this is primarily because of the increase in water absorption by the stone. If you install any Petracraft Stone in a horizontal position, it is highly recommended that you seal the stone and maintain the integrity of the sealer for the life of the stone. Stone installed horizontally is not covered under warranty.