Add new joist hangers on top of old?

[atgcpaul]

Can you add new joist hangers on top of old ones?  Every joist hanger that is attached to my deck ledger is rusted at the bottom where the joist sits.  Can I slip another joist hanger over the existing one and then screw (with the proper screws) or nail then in place without having to remove the old hanger?  Do they sell slightly wider hangers?

[blackhat]

I’ve never seen such a beast. Swapping them one at a time by pulling the old fasteners and swap for new shouldn’t be terrible. Why are they rusting?  Wrong hangers on ACQ lumber?

[tomsteve]

no way the holes would line up. they typically arent hard to pull off with a flat bar and cats paw

[Splinter Puller]

I'd grind and pull of the old ones but they do sell wider joist hangers.   You can get them for LVL lumber at 1-3/4" wide.   But, just pry the old ones out.  The old nails will probably be fairly loose.   Use longer nails on the new ones.

[Cooler]

A suggestion: 

I replaced all the under-structure to my deck piece meal (the deck can be repaired, but I could not replace it because of building codes).

A palm nailer is probably the best investment I made for that project (along with a Sawzall).  

Palm nailers are not very expensive, so I recommend it heartily.

Do note that "hot dipped" galvanized is vastly superior to cold galvanized nails.  The hot dipped zinc adheres extremely well to the steel.  Not so with cold galvanized; indeed sometimes the zinc will flake off the heads of the nails just by hammering them in.

If it does not says specifically that it is hot dipped, then it is probably cold galvanized (also called "impact plated").

Cold galvanizing entails placing the parts in a drum with pellets of zinc, and then tumbling the drum.  Eventually some of the zinc adheres to the nails.

These nails are hot dipped and say so on the package.



These nails do not say "hot dipped" and are almost certainly cold galvanized, and are substandard.

[Roly]

A suggestion: 

I replaced all the under-structure to my deck piece meal (the deck can be repaired, but I could not replace it because of building codes).

A palm nailer is probably the best investment I made for that project (along with a Sawzall).  

Palm nailers are not very expensive, so I recommend it heartily.

Do note that "hot dipped" galvanized is vastly superior to cold galvanized nails.  The hot dipped zinc adheres extremely well to the steel.  Not so with cold galvanized; indeed sometimes the zinc will flake off the heads of the nails just by hammering them in.

If it does not says specifically that it is hot dipped, then it is probably cold galvanized (also called "impact plated").

Cold galvanizing entails placing the parts in a drum with pellets of zinc, and then tumbling the drum.  Eventually some of the zinc adheres to the nails.

These nails are hot dipped and say so on the package.



These nails do not say "hot dipped" and are almost certainly cold galvanized, and are substandard.

Just use joist hanger nails, they are the correct strength and proper coating for treated wood and rust prevention. A inspector may not ok other than hanger nails.  Roly

[Turner52]

You could also go with double joist hangers on each one. This would move the nail holes out wider if you centered them on the existing. It would also give you the bottom suport you need.

[joe1086]

Just went through this....most nails were fairly easy just to pull out. Others I cut off with a oscillating too.  Works better if the joists were toe nailed in before the hangers were installed. DAMHIKT

[Cooler]

When I first moved into the house some 24 years ago, I knew that some of the deck's joists had to be replaced.  None of the contractors wanted to build a new deck as it was built over a steep slope and required footings about 10 feet deep.  One contractor quoted me $3,500.00 per post ($14,000.00 total) just to install new posts.  I think he really did not want the job.

In any case I hired a "contractor" from Lowes to replace the two worst joists.  He re-used the old joist hangers (from 1953) and installed them using plated dry wall screws. 

I ended up replacing those joist hangers right away and doing the rest of the replacements myself. 

Drywall screws?  Really?

He said,"They're fine; I used the zinc plated ones.".

[DieselDennis]

When I first moved into the house some 24 years ago, I knew that some of the deck's joists had to be replaced.  None of the contractors wanted to build a new deck as it was built over a steep slope and required footings about 10 feet deep.  One contractor quoted me $3,500.00 per post ($14,000.00 total) just to install new posts.  I think he really did not want the job.

In any case I hired a "contractor" from Lowes to replace the two worst joists.  He re-used the old joist hangers (from 1953) and installed them using plated dry wall screws. 

I ended up replacing those joist hangers right away and doing the rest of the replacements myself. 

Drywall screws?  Really?

He said,"They're fine; I used the zinc plated ones.".

At least he used something you could remove easily.