Over Open Studs

Apply paper-backed galvanized 3.4 lbs. 3/8” rib expanded metal lath to the studs using galvanized nails or staples every 6” vertically on stud centers with a minimum penetration of 1”.  Overlap lath sides no less than 1/2” and ends no less than 1”.

For metal studs use corrosion-resistant self tapping screws with a 3/8" head that provides a minimum 1/2” penetration beyond the inside metal surface.

Over Wood Products

Cover the wall surface (plywood, drywall, paneling, etc.) with a weather resistant (15 pound felt) barrier, lap joints by applying felt horizontally with the upper layer lapped over the lower layer not less than 2” and end laps not less than 6”.  Install a minimum of 2.5 lbs diamond mesh metal lath. Use galvanized lath for exterior and black metal lath (non-galvanized) may be used for interior.

Lap lath sides not less than ½” and end laps not less than 1”.  Please note it is critical that the lath is attached with the small diamonds pointing upwards.  On the inside and outside corners turn the corner 16” minimum each way.

Attach wire lath using a minimum of 1 ½ “ galvanized nails or Staples on 6” centers vertically and to centers horizontally penetrating studs a minimum of I”.

After attaching the lath, apply a mortar scratch coat to cover the metal lath and apply the stone while the scratch coat is still moist.  If the scratch coat dries before applying the stone, the scratch coat should be remoistened by spraying it with water.

Over Rigid Insulation Board

Surface preparation is the same as wood related sheathing with the following exceptions: Nails should be 4” on center vertically and 16” on center horizontally penetrating studs a minimum of 1”.

Metal Panels

Surface preparation is the same as wood sheathing, except the lath should be attached with self-tapping screws with a minimum 3/8” head that provides 1/2” minimum penetration beyond the inside metal surface.

Clean Untreated Masonry

No Special preparation is needed. Note: On newly poured concrete examine the area for release agents (form oils). If present, the surface must be etched using an appropriate acid or Sand Blasting.  If acid is used, rinse thoroughly before proceeding.

Painted, Sealed, or Dirty Masonry

You must clean the surface down to the masonry by sandblasting, water blasting, acid etching or wire brushing before installing stone veneer.  If you are unable to use the above methods you may elect to attach metal lath without a vapor barrier.  Attach lath with corrosion-resistant nails or other approved fasteners.

Note:  If sand blasting is used, you must wash the surface prior to applying stone.