Construction Industry/Joist hangers


How does one replace rotted ,rusty joist hangers on a wooden deck. Do we need to raise the structure. What is the process. The wood decking and the joist boards are ok, just the rusty joists are causing decking to warp etc.

Hello Deb,

Joist hangers are generally nailed to the supporting beam and form a pocket to received the joist.  There are several designs of joist hangers.  To replace the rusted hangers, select one that is a different style from the current hangers.  Also, I assume the existing hangers are not nailed on the top of the beam.     
You've got a tedious job ahead of you.  I assume that there is a crawl space below the joists which commonly is a shallow depth making it difficult to move and work.
The old hangers must be replaced one at a time.  That is to say - don't remove the old hangers without installing the new hanger immediately.  The decking usually runs opposite the joists and is spaced using a #10 spike between planks while being nailed in place.  The two or three spikes are moved to the next plank to provide a uniform and consistent spacing.
The main reason for selecting a different hanger style is to avoid using the same nail holes when replacing the hanger.  Also, you may use screws rather than nails because a power screw driver is easier to use that a hammer when you don't have much swing space.
Another method you might consider: if the joists are a smaller measurement that the beams they hang from, you can install a ledger member below the joists.  For example:  The beam is 4"x 10" (which is actually 3-1/2" x 9-1/2") and the joist is 2"x 8" (1-1/2" x 7-1/2")  A 2" x 4" ledger can be attached to the beam with 3" wood screws about 12" on center.  The joist hangers can be abandoned.
I hope this was helpful.

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Roger Zona


I am experienced in all types of construction: residential, industrial and commercial; single family, multi-family, mid-rise and high rise buildings (16 story office building) as well as remodeling, additions and tenant improvements. I can field most any question that relates to general construction. I have consulted with infrastructure (utility) contractors also and have a good general knowledge of underground utility construction for subdivisions and commercial projects.


After college, I began my career in the construction industry. I chose to become an apprentice Architect and 4 yrs later I opened my own architectural design firm. Six years later I moved to Florida to buy & develop land and build. I became a State of Florida Certified General Contractor and operated my business for 45 years. I built all types of residential and commercial buildings including warehouses, shopping centers, high rise apartments and office buildings and developed sites for other contractors. I retired and became a consultant to the construction industry. I maintain my license and continuing education requirements, operate a small construction company and write a weekly newspaper column for the Palm Beach Post (a Cox publication) with the byline "Ask The Contractor". I am the "technical editor" for a publisher of books that relate to home maintenance.

Previously - NAHA Currently - FLCA (Florida Licensed Contractors Assoc.)

Palm Beach Post newspaper - weekly Q & A column Happy Herald monthly real estate publication - monthly column

Michigan State University University of Detroit BS in Engineering

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I built a home in Palm Beach for a member of the Pulitzer Family. I was responsible for the completion of a twin hi-rise condominium project for G.E. Credit. I was a partner in the successful development of a P.U.D. (Planned Urban Development) subdivision. I represented the largest home builder from France (Bati Service, S.A.) in the development of a subdivision and the design and construction of the homes.

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