RPBZ Retrofit Post Base
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The RPBZ retrofit post base is designed to reinforce existing posts and columns. The single, versatile model will fit on any size post consisting of a double 2x4 or larger. RPBZ can also be used to reinforce new post-base connections, such as braced carports, patio covers, decks and other structures. The RPBZ can be installed with the CPS composite plastic standoff to meet a 1" post standoff code requirement. A single RPBZ can be installed on a post that is flush to a corner, and two RPBZs can be installed at away-from-edge conditions to fortify the post-base connection to resist both wind and seismic forces.
Strong-Drive® SDS Heavy-Duty Connector screws install easily and provide excellent holding strength for post-to-flange connections. Additionally, the RPBZ can be purposed as a temporary base fixture for posts when shoring beams. RPBZ comes standard in ZMAX® finish to meet exposure conditions in many environments. See additional Corrosion Information.
- 12 gauge
- ZMAX coating
- Use all specified fasteners; see General Notes.
- 1/4" x 1 1/2" Strong-Drive SDS Heavy-Duty Connector and base connection fasteners are not provided with RPBZ. Simpson Strong-Tie CPS series composite post standoff sold separately.
- Post bases do not provide adequate resistance to prevent members from rotating about the base and therefore are not recommended for non-top-supported installations, such as fences or unbraced car ports.
RPBZ Connector-Only Values
- See footnotes below.
RPBZ Anchorage-to-Concrete Values
- Allowable load for design shall not exceed minimum of Connector Only Value and Anchorage to Concrete Value.
- Allowable connector loads are based on DF/SP lumber. For SPF/HF, multiply table loads by 0.86.
- Double 2x4s may be used in lieu of 4x4 post.
- For installation on 6x or larger members, if four RPBZ post bases are used, allowable loads may be taken to be 1.5 x the tabulated two-part value.
- For installations into concrete, the minimum compressive strength is f'c = 2,500 psi. Designer is responsible for concrete member uplift design.
- Away-From-Edge loads require face of wood post to be a minimum of 2 1/2" away from near edge of concrete on all four sides of the post.
- Allowable anchorage to concrete uplift and shear loads for the 3/8" diameter anchors are calculated per ACI 318-19. Shear loads assume cracked concrete while uplift loads consider both cracked and uncracked concrete values, and all are qualified for Wind and Seismic Design Categories A&B.
- Embedment depth for these post-install anchors must be a minimum of 2 3/4" and are for use with SET-3G™ or AT-XP® structural anchoring adhesives or Titen HD® screw anchors.
- Allowable uplift and shear loads for the Titen Turbo™ masonry screws do not carry a particular “cracked” or “uncracked” designation.
- Titen Turbo masonry screws and non-stainless-steel Titen HD screw anchors should be used only in interior-dry and non-corrosive environments.
- For connection to wood framing, loads are based on penetration of the Strong-Drive® SDS Heavy-Duty Connector screw’s entire threaded section into the main member. If thread penetration into the main member is less than the “Thread Length” as shown in the table for DF/SP, reduce allowable load by 172 lb./in. of thread not in the main member. Use 121 lb./in. for SPF/HF. Exception: installations onto 5/4" southern yellow pine deck boards where screw tips protrude through the backside achieve full load.
Code Reports & Compliance