Tie Down Concrete Foundation System - Manual

Xi2
Concrete System
(For Block or Steel Pier)
Xi2 Concrete System
with Longitudinal Stabilization
(One Strut for Wind Zone I
Two Struts for Wind Zones II & III)
Instruction #08107
101113,D974
Concrete Foundation System
Installation Instructions for Wind Zone I, II & III
(Except Florida and California)
By Tie Down Engineering
Updated: 10/11/2013
REQUIREMENTS
• Install in any type soil, 4B (175 – 275 lbs.) or better.
• Main Rail spacing must be 75.5” – 99.5”, 112” exception with proper strut.
• Maximum pier height at system is 48”.
• Wind Zones II & III require sidewall anchors for up lift, check manufacturers requirements.
• Poured concrete must be must be 2.500 PSI minimum at 28 days. Bottom of footers must be below the frost line or a
minimum of 4” below finished grade, check with authorities for local requirements (LAHJ).
•
Footer Requirement: Must to be large enough for the pier load at that location and be a minimum of 22” wide
by 6” deep with anchor wedge bolts a minimum of 4” from any edge or 18” wide by 12” deep with anchor wedge
bolts a minimum of 1 ½” from edge. Strip footings minimum of 18” wide by 14’ long by 6” deep or 27” wide by 14’
long by 4” deep.
• Maximum vertical projection at sidewall is 9’ (wall and eave). Higher walls may be used when design loads are
adjusted accordingly.
• Longitudinal strut angles need to be no more than 50 degrees and no less than 25 degrees. See page 4.
• Longitudinal stabilization is easily added with Tie Down’s unique multi sided bracket. The longitudinal component of the
Xi2 System replaces end frame ties. Check manufacturer’s set-up requirements.
• The Xi2 System is installed on one of the pier footers required by the home manufacturer set up instructions.
• Two systems designed to work in conjunction with each other must be placed as evenly as possible. Measuring from
the center of the block/pier, systems are to be placed no less than 2’ and no more than 10’ from each end of home.
Additional systems per instructions, see page 3. Components of the Xi2 System such as the longitudinal strut and
connecting hardware, may extend beyond the pier location.
• For roof slopes greater than 20 degrees, (4.37” in 12” Pitch) see page 3.
• This System only replaces normal lateral frame tie and or longitudinal end tie anchorage. The home manufacturer may require
additional vertical anchor ties that are unique to a home’s design. These locations may include shear walls, marriage line ridge
beam supports, and rim plates. Check the manufacturer’s installation instructions for set-up requirements.
Xi2 components exceed HUD code 3280.306 g “Anchoring equipment exposed to weathering shall have a resistance to
weather deterioration at least equivalent to that provided by a coating of zinc on steel of not less than 0.30 ounces per
square foot of surface coated.