CPTZ ZMAX Galvanized Concealed Post Base for 4x4 Nominal Lumber

A:  Hello Jem, This is Colin from Simpson Strong-Tie. The Concealed Post Tie for a 4x4 column (CPT44Z) was developed and tested to be installed on a horizontal concrete base. If you need more information or have additional questions, please contact the Simpson Strong-Tie Customer Service team at 800-999-5099. We look forward to hearing from you.

A:  Hi lilbrunedbear, this is Colin from Simpson Strong-Tie. Our CPT have a ZMAX finish, which is a medium level corrosion resistant finish comparable to hot dip galvanized. It can be used with certain Pressure Treated wood, but the PT wood supplier will have a evaluation report for corrosion resistance recommendations. If you need more information or have additional questions, please contact the Simpson Strong-Tie Customer Service team at 800-999-5099. Thank you.

A:  ​Hi logan, This is Colin from Simpson Strong-Tie. The Concealed Post Tie (CPT44Z) requires two 1/2" diameter anchor bolts into concrete to achieve the published Allowable Uplift and Lateral Load values. These load values would not apply if the 1/2" diameter anchor bolts are installed into brick. ​It is important to ensure the published capacity satisfies the anticipated load for your project. If you are unsure, we recommend consulting with a qualified designer and/or your local building department. On our website strongtie.com enter CPTZ in the search box on our home page and click the picture of the post base for more information. If you have additional questions, please contact the Simpson Strong-Tie Customer Service team at 800-999-5099.

A:  Yes, but it sounds like you may want to run your rafters 12 inches on center, but as long as you use 2" or longer lag bolts into the concrete you should be good.

A:  We can direct you to the allowable load table (link below), but it would be up to the Designer/ Engineer of Record to specify the appropriate connector(s) based on framing layout, demand loads, local building code, etc. Thank you! Load table: https://www.strongtie.com/retrofitpostbases_postbases/cptz_base/p/cptz#LoadTables