Fox Blocks
Airlite Plastics Co.
6110 Abbott Street
Omaha, NE 68110
877.369.2562
www.FoxBlocks.com
Drywall Attachment
Fox Blocks stay-in-place insulating concrete forms (ICFs) are used in all types of residential and commercial
applications. Fox ICF walls provide unparalleled energy efficiency, safety, durability and comfort.
Fox Blocks ICFs features a flat interior configuration. It contains plastic polypropylene ties or studs that hold the form
together during concrete placement and later serve as the furring strips for fastening interior and exterior finishes.
The Fox Blocks studs are spaced vertically 8" (203.2 mm) on center and are 1 1/2” (38.1 mm) wide and 0.23" (5.8 mm)
thick. The studs are recessed 5/8" (15.9 mm), but are clearly marked with a raised expanded polystyrene (EPS) bead on
both sides of the stud. This makes it easy for the baseboard installer to find the studs to fasten to. The Fox Block
installer stacks the forms in a running bond pattern aligning the studs so that they create a continuous vertical furring
strip.
On the Fox 45 and 90º corner forms, the closest studs to the apex of the corner on each return are centered at the
following distances from the corners:
90-Degree
Inside Return
90-Degree
Outside Return
45-Degree Inside
Return
45-Degree
Outside Return
9 1/4"
11 1/4"
13 1/4"
15 1/4"
17 1/4"
(235 mm)
(286 mm)
(336 mm)
(387 mm)
(438 mm)
1" and 9”
1" and 9”
1" and 9”
1” and 7”
1" and 9”
(25.4 and 228.6
mm)
(25.4 and 228.6
mm)
(25.4 and 228.6
mm)
(25.4 and
177.8 mm)
(25.4 and
228.6 mm)
10", 6”, 2 ½”
12", 6”, 2 ½”
14", 6”, 2 ½”
16", 6”, 2 ½”
18", 6”, 2 ½”
(254, 152, 63.5
mm)
(305, 152, 63.5
mm)
(356, 152, 63.5
mm)
(406, 152, 63.5
mm)
(457, 152, 63.5
mm)
N/A
N/A
N/A
N/A
2” and 10”
2" and 9”
2" and 10”
(51 and 254mm)
(51 and 229
mm)
(51 and 254mm)
2” and 6"
2” and 6"
2” and 8"
(51and 152 mm)
(51 and 152 mm)
(51 and 203mm)
All of the 45 and 90 degree corner forms have a corner bracket molded into the 90-degree corner forms. This corner
bracket provides a 1 1/2" (38.1 mm) wide continuous fastening strip right in the apex of the corner. There is another 1
Fox Blocks
Airlite Plastics Co.
6110 Abbott Street
Omaha, NE 68110
877.369.2562
www.FoxBlocks.com
1/2" (38.1 mm) wide continuous vertical furring strip that is centered 6 inches (152.4 mm) from the corner’s apex.
Additionally there is a 1 1/2" (38.1 mm) wide fastening strip running perpendicular to these two vertical strips. This
horizontal strip will be staggered vertically and located approximately every 7 to 9 inches (177.8 to 228.6 mm). All of
the fastening strips are recessed 5/8" (15.9 mm) beneath the face of the EPS foam face. Therefore, the 9 ¼” will have
continuous fastening strips located 2 1/2 inches, 6 inches and 10 inches (63.5, 152.4, and 254 mm) from the outside
corner, the 11 1/4" will have continuous vertical fastening located 2 ½” inch, 6 inches and 12 inches (63.5, 152.4. and
305 mm) from the outside corner, the 13 1/4" will have a fastening strip located 2 ½” inch, 6 inches and 14 inches
(63.5, 152.4. and 356 mm) from the outside corner, the 15 1/4” will have a fastening strip located 2 ½” inch, 6 inches,
and 16 inches (63.5, 152.4, and 406.4 mm), and the 17 1/4” will have a fastening strip located 2 ½” inch, 6 inches, and
18 inches (63.5, 152.4. and 431.8 mm).
15-Minute Thermal Barrier Requirement. All model building codes require that the interior face of the foam
insulated wall for all buildings be finished with an approved 15-minute thermal (fire) barrier, such as minimum ½" (12.7
mm) thick regular gypsum wallboard attached to the plastic studs. This requirement includes unfinished basement areas
and some crawl spaces. Other building materials documenting the ASTM E-119 fire index rating of 15 would be
acceptable.
Hanging Drywall
Run the drywall sheets horizontally rather than vertically. Since Fox Block walls provide a solid continuous foam and
concrete substrate behind the drywall, it is not necessary to butt two sheets of drywall over the plastic ties, thus saving
time and waste.
Fasteners
Use course thread, sharp-pointed #6, #8 or #10 drywall screws for fastening the drywall to the Fox Block wall, because
they have more pullout strength than fine thread screws. Use a cordless drill set at its lowest power setting rather than
an electric drill when fastening the screws into the plastic studs molded into the forms. Bring it to snug tight and stop
to prevent stripping out the plastic stud. Always follow the local building code jurisdiction regarding the fastening
schedule.
Adhesives
Some drywall contractors use a combination of screws and adhesive when hanging the drywall. This method is
acceptable as long as the adhesives are compatible with and approved for use on EPS foam materials. Petroleum or
solvent-based products will deteriorate the foam.
Heavy Objects
The plastic studs work well for fastening drywall and lightweight objects to the wall. But when hanging heavy objects,
such as cabinets and large pictures, you should fasten directly to the concrete using expansion bolts or concrete screws.
To do this, remove the foam from the concrete and replace the removed foam thickness with wood. Fasten the wood
directly to the concrete, and then fasten the heavy object to the wood.
Another way to hang heavier objects is using a 4" by 8" (101.6 by 203.2 mm) metal Grappler plate by Wind-Lock Select.
Simply pin the Grappler to the foam wall before hanging the drywall. The Grappler becomes a locking washer when
sandwiched between the foam and drywall. Place the Grappler where you are planning to hang the following items on
the wall: electrical fixtures, thermostats, HVAC fixtures, plumbing fixtures, bathroom accessories, shelving supports,
Fox Blocks
Airlite Plastics Co.
6110 Abbott Street
Omaha, NE 68110
877.369.2562
www.FoxBlocks.com
mirrors, coat racks and rods, curtain rods, smoke detectors, door bells and any wall hangings. Since the Grappler is
metal, it can be located behind the drywall with a stud finder.
Window Sills and Jambs
The Fox Blocks insulating concrete walls provides a thicker than normal wall cross-section creating wider window wells.
Drywall can be returned into the window sills and jambs. Another method would be to order jamb and sill extensions
from the window manufacturer.