Fox Blocks
Airlite Plastics Co.
6110 Abbott Street
Omaha, NE 68110
877.369.2562
www.FoxBlocks.com
Plumbing
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
1/2" (38.1 mm) wide continuous vertical furring strip that is centered 6 inches (152.4 mm) from the corner’s apex.
Fox Blocks
Airlite Plastics Co.
6110 Abbott Street
Omaha, NE 68110
877.369.2562
www.FoxBlocks.com
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" iForm 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.
Wall Penetrations
Install wall penetration sleeves that run from the exterior to the interior of Fox Block walls prior to concrete placement.
Installing the penetrations prior to pouring is important to avoid the expense of drilling a hole through the reinforced
concrete wall
Lay-out and mark the location of any dryer vents, electrical, gas, phone, plumbing or telephone penetrations on the
interior and exterior face of the wall, using the sleeve as a template to mark the location. Then cut the hole through the
foam plug from both faces of the form the using a keyhole saw so that the sleeve will be snug tight. Be sure to pay
attention to the location of horizontal and vertical steel reinforcement when locating the wall penetrations. If an
oversized hole is cut, use expanding foam to fill in any gaps to prevent air infiltration leaks.
Before placing the concrete in the Fox Block wall, insert a metal or PVC sleeve, which is the length of the overall
thickness of the Fox Block form. The sleeve should be slightly larger than the pipe penetrating through the wall. Some
builders like to have the length of the sleeve sticking out the interior and exterior sides of the wall and cut off the extra
length after placing the concrete. The sleeve should be water sealed with compatible foam and waterproofed with a
caulk compatible with EPS foam. For drainage purposes insert the sleeve at a slight angle so that the exterior side of the
sleeve is slightly lower than the interior side of the sleeve.
Plumbing Chases
Cut plumbing chases into the EPS foam of the Fox Block stay-in-place forms after the concrete has been placed into
the Fox Block wall. The chases are used to run smaller diameter pipe behind the drywall along the face of the wall.
When placing pipe within the foam, the maximum diameter of pipe and fittings is determined by the foam thickness.
The Fox Block maximum foam thickness to run pipe chases is 2 5/8" (66.7 mm). Place the pipe in the chase and hold
it in place with compatible adhesive, expansion foam, or strap fastened to the nearest plastic studs.
Fox Blocks
Airlite Plastics Co.
6110 Abbott Street
Omaha, NE 68110
877.369.2562
www.FoxBlocks.com
You can place vertical chases anywhere within the wall when following the foam thickness guide. It is best to run
horizontal chases between the horizontal joints of the stacked forms when ever possible. This will avoid the
interference of running into the plastic ties. When this is not possible, cut through the plastic tie.
Most installers use an electrical hot knife for cutting the chase into the foam. The hot knife should come with a depth
stop, so it can be adjusted to the required depth. A router may also be used, but it does not provide the clean and
professional results that a hot knife does.
Fox Blocks does not recommend embedding pipe within the cavity of the form or concrete core. Doing so affects the
structural capacity of the wall and also places the pipe where it cannot be maintained. Instead, fur out the wall with
metal or wood studs or run the plumbing on an interior framed wall. If this is not an option be sure to have an
engineer review the structural design of the wall.