M ACdverti$er
Th e
omponent
anufacturing
Don’t Forget! You Saw it in the
Adverti$er
September 1st, 2016 #09206 Page #64
How to Select a Connector Series – Holdowns How Select a Connector — Holdowns How toto Select a Connector SeriesSeries – Holdowns By Paul McEntee, PE, SE
By Paul McEntee, PE, SE
This article discusses how to select holdowns and tension ties, which are key components in a continuous load path. They
This article holdowns and tension ties,uplift which are key components in a continuous load path. They are used to discusses resist uplifthow dueto toselect shearwall overturning or wind forces in light-frame construction. In panelized roof are used to resist uplift due to shearwall overturning or wind uplift forces in light-frame construction. In panelized roof construction, holdowns are used to anchor concrete or construction, holdowns are used to anchor concrete or masonry walls to the roof framing. masonry walls to the roof framing. Holdowns can be separated in two basic categories – post-installed cast-in-place. Cast-in-place holdowns, Holdowns canand be separated in two basic categories – like the STHDand holdowns or PA purlin anchors, are post-installed cast-in-place. Cast-in-place holdowns, straps that are installed at the time of concrete like the STHD holdowns or PA purlin anchors, are
placement. They are attached with nails to wood framing
straps that are installed at the time of concrete
or with screws to CFS framing. After the concrete has
placement. They are attached with nails to wood framing been placed, post-installed holdowns are attached to
or with screws to CFS framing. After the concrete has
anchor bolts at the time of wall framing. The attachment
been placed, post-installed holdowns are attached to to wood framing depends on the type of holdowns
anchor bolts the timemodels of wall using framing. TheSimpson attachment selected, withatdifferent nails, to wood framing depends on the type of holdowns Strong-Tie® Strong-Drive® SDS Heavy-Duty
selected, with different models using nails, Simpson Connector screws or bolts. Strong-Tie® Strong-Drive® SDS Heavy-Duty A third type screws of overturning restraint is our anchor Connector or bolts. tiedown system (ATS), which is common in multistory construction with large uplift forces.is (I our discussed A third type of overturning restraint anchorthe
system insystem this blog post.) tiedown (ATS), which is common in multistory
construction with large uplift forces. (I discussed the system in this blog post.)
Given the variety of different holdown types, a common question is, how do you choose one? For prescriptive designs, such as the IRC portal frame method, the IRC or IBC may require a cast-in-place strap-style holdown. (Randy Shackelford did a great write-up on the PFH method in this post.) For engineered designs, a review of the design loads may eliminate some options and help narrow down the selection.
Holdown Type Cast-in-Place Nailed SDS Screws Bolted
Maximum Load (lb.) 5,300 5,090 14,445 19,070
PHONE: 800-289-5627
Read/Subscribe online at www.componentadvertiser.com
FAX: 800-524-4982