24 C.F.R. § 3285.401 – Anchoring instructions.

(a) After blocking and leveling, the manufactured home must be secured against the wind by use of anchor assembly type installations or by connecting the home to an alternative foundation system. See § 3285.301.
(b) For anchor assembly type installations, the installation instructions must require the home to be secured against the wind, as described in this section. The installation instructions and design for anchor type assemblies must be prepared by a registered professional engineer or registered architect, in accordance with acceptable engineering practice, the design loads of the MHCSS, and § 3285.301(d).
(c) All anchoring and foundation systems must be capable of meeting the loads that the home was designed to withstand required by part 3280, subpart D of this chapter, as shown on the home's data plate. Exception: Manufactured homes that are installed in less restrictive roof load zone and wind zone areas may have foundation or anchorage systems that are capable of meeting the lower design load provisions of the Standards, if the design for the lower requirements is either provided in the installation instructions or the foundation and anchorage system is designed by a professional engineer or registered architect.
(d) The installation instructions are to include at least the following information and details for anchor assembly-type installations:
1. (1) The maximum spacing for installing diagonal ties and any required vertical ties or straps to ground anchors;
2. (2) The minimum and maximum angles or dimensions for installing diagonal ties or straps to ground anchors and the main chassis members of the manufactured home;
3. (3) Requirements for connecting the diagonal ties to the main chassis members of the manufactured home. If the diagonal ties are attached to the bottom flange of the main chassis beam, the frame must be designed to prevent rotation of the beam;
4. (4) Requirements for longitudinal and mating wall tie-downs and anchorage;
5. (5) The method of strap attachment to the main chassis member and ground anchor, including provisions for swivel-type connections;
6. (6) The methods for protecting vertical and diagonal strapping at sharp corners by use of radius clips or other means; and
7. (7) As applicable, the requirements for sizing and installation of stabilizer plates.