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Structural connectors, fasteners, bolts, nails, joist hangers, rafter ties etc.: this article explains the proper selection and installation of structural connectors, brackets & tie plates used to connect deck or porch framing and support members. USP connectors such as joist hangers, joist angles, joist supports, stud shoes, skew hangers, and face mount hangers used for connecting these hangers and connectors are described, their uses explained, and their applications and specifications linked. Both galvanized steel and stainless steel joist hangers, connectors, & brackets may be applied. Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman. How to Choose the Correct Bolts or Fasteners for Structural Framing Connections in Wood Frame Construction, Decks & Porches Details about choosing the right structural connectors for decks and how they should be installed are at Fasteners/Connectors, Ties, Structural. At Fasteners, Nails, Screws, Hidden, for Decks we discuss choosing the proper nail, screw, or hidden fastener for fastening deck boards, railings, or joist hangers. Spans, sizes and spacings for deck joists and deck beams are discussed in detail at FRAMING TABLES, SPANS for DECKS and are shown in Table 4-7 and Table 4-8. Basic building framing information is found at FRAMING SIZE & Spacing, Age, Types. Also see Deck Framing Tables, Spans and Deck & Porch Connections: Ledger Boards. And see Preservative-Treated Framing Lumber. see Rot-Resistant Deck Lumber & Flooring for a discussion of lumber and flooring alternatives to preservative-treated wood. At minimum, all structural hardware for decks should be hot-dipped galvanized steel. For the best protection, use stainless steel (see “Joist Hangers and Connectors,” below). At connections carrying structural loads, such as deck ledgers or railing posts, use through-bolts or lag screws. Through-bolts are stronger and should be used where possible. For the heaviest connections on a deck, such as where ledgers attach to the house or to posts, use 1/2-inch bolts or lags. Place large washers under the heads of lags and at both ends of through-bolts. Re tighten bolts and lags after the first year and check periodically for tightness. Machine-Threaded Bolts Used for Deck Construction
After drilling, saturate the hole with preservative. Use large washers under both the head and nut. Re tighten after the first year, since the wood may have shrunk. Lag Bolts Used for Deck ConstructionFor lag bolted deck connections, drill a full-diameter pilot hole for the unthreaded portion and a smaller hole (65 to 75% of the lag’s diameter) for the threaded portion. So, for example, a 1/2-inch lag would get a 5/16-inch pilot hole for the threaded portion; a 3/8-inch diameter lag would get a 1/4-inch diameter pilot hole. After drilling, saturate the pilot hole with wood preservative. It is also important that at least half the length of the lag is threaded into solid wood. For example, driving a 5-inch lag through a 4x4 post into a 2x joist will produce a weak connection with only 1 1/2 inches of anchoring. Instead, the lag screw should go through the 2x and be threaded into the thicker 4x4. Use a large washer under the head, and re tighten after the first year in case materials have shrunk. Joist Hangers and Steel Connectors Used for Deck ConstructionAt a minimum, use hot-dipped galvanized hardware. With pressuretreated wood, hot-dipped galvanized steel should conform to ASTM A153 (for fasteners) or ASTM A653, G185 (for connectors). Stainless steel offers the best protection. Type 304 or higher stainless steel is recommended for very wet environments such as poolside decks; or Type 326 for exposure to salt or saltwater. Watch out: Also, do not mix metals: Use stainless-steel fasteners with stainless-steel connectors and galvanized fasteners with galvanized connectors. And at Fasteners, Nails, Screws, Hidden, for Decks we include examples of fasteners that should not be used in joist hangers, such as drywall screws and other non-structural screws. or roofing nails. Also see Deck Nails, Screws, Hidden Fasteners and see New Preservatives and Corrosion where we describe structural fasteners designed for use in pressure-treated lumber. Suppliers of Joist, Post & Beam Hangers & Connectors & the Nails or Fasteners used With Them
-- Adapted with permission from Best Practices Guide to Residential Construction. Also see DECK COLLAPSE Case Study (collapse of a new code-approved deck) and DECK FLASHING LEAKS, ROT Case Study for an example of an older deck with rot and collapse due to improper construction and missing building flashing. Frequently Asked Questions (FAQs) about framing connectiors, fasteners, joist hangers, rafter ties... Ask a Question or Search InspectApediaQuestions & answers or comments about what types of joist & beam hangers & connectors are required for deck construction: joist hangers, connectors, steel tie plates, etc. . Ask a Question or Enter Search Terms in the InspectApedia search box just below. Technical Reviewers & ReferencesRelated Topics, found near the top of this page suggest articles closely related to this one.
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The Home Reference Book - the Encyclopedia of Homes
