Stone and Stucco

InSoFast panels are ideally suited as a drain and dry insulation board for use under traditional stucco and thin-veneer stone applications. The panels utilize tongue and groove edges to provide a smooth continuous insulation substrate and include built-in studs for lath attachment. The InSoFast panel has drainage channels which are flashed to drain bulk water.

Flashing, Weather Resistive Barriers, and Concrete Sealers


It is important to properly flash and seal all penetrations through the InSoFast panels. See stucco manufacturer’s specifications and details which supersede the generic InSoFast details.

For wood or steel framed structures, InSoFast panels must be installed over sheathing with a weather resistive barrier. The weather resistive barrier must be properly sealed and flashed so that bulk water can move down the drainage channels of the InSoFast panels and exit out weep screed or drains at openings, penetrations, and bottom of the wall.

For concrete or masonry CMU walls, follow local building codes and stucco manufacturer’s instructions for proper flashing and sealants. Make sure to properly manage bulk water from the drainage channels into weep screeds or drains at openings, penetrations, and bottom of the wall.

Lath Attachment

Attach lath to InSoFast studs using #6 to #8 sharp-point, coarse thread screws.

Consult local building codes for screw type, spacing, and wind loading while following stucco manufacturer’s specifications and referencing InSoFast testing noted below.