Your installation questions answered
Frequently asked questions
Can PermaBASE® be screwed on with the same screws used for gypsum boards?
We recommend the use of a screw with a very large trumpet head, which will press the board firmly against the mounting studs or furring, thus avoiding any vibrations. Also, in very humid areas and/or for exterior use, the use of an anti-corrosive, high-performing screw is highly advisable (do not use drywall or galvanized screws there!).
What kind of fasteners do I use to install PermaBASE® Cement Board?
Corrosion-resistant screws or galvanized roofing nails. We strongly suggest PermaBASE™ Cement Board Screws.
What kind of fasteners do I use to install PermaBASE UltraBacker® Cement Board?
Corrosion resistant screw or galvanized roofing nails. Strongly suggest PermaBASE screws since they do not have nibs like competitor screws.
What kind of fasteners do I use to install PermaBASE PLUS® Cement Board?
Corrosion resistant screws or galvanized roofing nails. Strongly suggest PermaBASE screws since they do not have nibs like competitor screws.
What is the fastener spacing for floor applications?
Every 8” o.c. along the perimeter and field of board.
What is the fastener spacing for interior wall applications?
Every 8” o.c. along the perimeter and field of board.
What is the depth of fastener placement in wood and metal?
Long enough to go into woods studs ¾” and metal framing 3/8” (min. three threads).
What do I tape the PermaBASE® Cement Board joints with?
4” wide alkali-resistant PermaBASE™ Cement Board Tape for all exterior applications.
What do I use to tape the PermaBASE UltraBacker® cement board joints?
2” Alkali resistant mesh tape and mortar mix.
What do I tape the PermaBASE PLUS® cement board joints with?
2” Alkali resistant mesh tape and mortar mix.
Do I need to treat the joints on PermaBASE products?
All joints and corners must be finished with PermaBASE Cement Board Tape on approved mortars or basecoats.
Should I install the board vertically or horizontally?
Both methods are approved as long as you stagger the joints.
What is the height limitation for installing PermaBASE® Cement Board in the CBMV/PB system?
Low rise residential or commercial applications. Higher heights may be approved by a design professional.
When is it acceptable to install PermaBASE® Cement Board directly to the studs?
For interior applications. For exterior jobs, PermaBASE should always be installed over a primary sheathing and furring strips.
What is the required minimum gauge of the metal studs?
Minimum of 20 gauge or heavier.
What is the required joist spacing for floors?
For flooring applications with 16" o.c. floor joists, 5/8" tongue-and-groove exterior-grade plywood or 3/4" tongue-and -groove exterior-grade OSB may be used. For 19.2" o.c. and 24" o.c. floor joists, 3/4" tongue-and-groove exterior-grade plywood or OSB must be used. Tile size for floors with 24" o.c. floor joists must be 12" x 12" or larger. The joist and subfloor assembly must meet L/360 as well as the appropriate code tables for live and dead loads.
What is the required maximum stud spacing for walls?
16” o.c for wood and metal.
How do I create a waterproof installation?
All joints and fastener heads must be treated with waterproofing material to complete the waterproof installation.