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Use of Connectors and Brackets
Home Builder’s Guide to Coastal Construction
FEMA 499/June 2005
Technical Fact Sheet No. 17

Purpose: To highlight important building connections and illustrate the proper
use of various types of connection hardware.

Key Issues
--In high-wind regions, special hardware is used for most framing connections.
Toe-nailing is not an acceptable method for resisting uplift loads in high-wind
regions.
--Hardware must be installed according to the manufacturer’s or engineer’s
specifications.
--The correct number of the specified fasteners (length and diameter) must be
used with connection hardware.
--Avoid cross-grain tension in connections.
--Metal hardware must be adequately protected from corrosion (see NFIP Technical
Bulletin 8-96).
--Connections must provide a continuous load path (see Fact Sheet No. 10).

Proper fasteners must be used with connection hardware. Fill all nail holes with
specified fasteners, unless reduced nailing is specified by design. The length
and diameter of the fasteners must be as specified by the manufacturer or
engineer; some specifications require non-standard nails.

Avoid load path failure at roof-to-wall connections. Improper connection to only
one member of top place can lead to failure under uplift loads. Instead, nail
connector to outside face of both top plate members, or nail to stud and top
plate members.

Proper bracket connection. Offset bracket vertically to achieve minimum
specified end spacing for bolts. Bolt, screw, or nail diameter and quantity as
specified. Material to which bracket is attached must have adequate thickness
for maximum bracket capacity.

Truss member connections are made with metal plates that connect the individual
parts of a truss to form a structural component. Every joint must have a
connector plate on each face sized and positioned according to engineered
designs. Plates must be fully embedded, and gaps at joints should be minimized
(see ANSI/TPI-1 95).

Truss-to-Truss and Rafter-to-Truss Connections are made with metal hangers
specified by the truss designer.

Roof-to-Wall Connections are made with metal rafter ties or straps, sometimes
referred to as hurricane straps. These connectors replace toe-nailing and
provide added uplift resistance. The strap should extend above the centerline of
the rafter or, for the strongest connection, completely over the rafter.

Important
Coastal environments are conducive to rapid corrosion of metals. All connection
hardware must be properly protected. Galvanized coatings on readily available
hardware may not be adequate or in compliance with local coastal building codes.
Special-ordered hardware, re-galvanizing, field-applied coatings, or stainless
steel may be required.

Stud-to-Top-Plate Connections are made with metal straps, nailed to the side
and/or face of the stud and the top of the top plate. These connections replace
toe-nailing or end-nailing and provide added uplift resistance. The strap should
wrap over the top plate.

Stud-to-Stud Connections are made with nailed metal straps, or brackets with
threaded rods, that connect one story to the next.

Header Connections are made with nailed straps. They transfer accumulated uplift
loads from the header to the jack studs. The straps should extend the full depth
of header.

Joist-to-Beam Connections are made with ties similar to roof-to-wall connections
or with wood blocking.

Wall-to-Foundation Connections are made with metal brackets or bolts that
connect wall studs and/or sill plates to foundation walls, beams, or band
joists.

Continuous Rod Connections are made with a system of threaded rods, couplings,
and brackets. These connections can be used to tie the roof and walls to band
joists and support beams.

Pile Connections are made with special brackets, spiked grids, bolts, or other
types of connectors that attach the main floor beams to the piles. It is
extremely important to follow design specifications for this connection (see
Fact Sheet No. 13 for further details).

Important
These are examples of typical connectors used in residential construction. For
the required continuous load path to be maintained, all connectors used must be
adequate to resist the loads expected to act on them. Stronger connectors may be
necessary to areas subject to high winds or earthquakes.


Additional Resources
American National Standards Institute. National Design Standard for Metal Plate
Connected Timber Trusses, ANSI/TPI-1 95.
 

 

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