Deck Joist Hangers: What to Check
Rusted or under-nailed joist hangers weaken your deck. Learn what they do, the warning signs, and how The Great House replaces them.
OUTDOOR LIVING & DECKS
12/21/20263 min read
ASK MASON · DECK
Deck Joist Hangers: The Small Metal Parts Holding Up Your Deck
Mason shows what joist hangers do, the signs they’re failing, and how we fix them.
Every board on your deck hangs on small pieces of metal called joist hangers.
Watch Mason’s video, then read how they work, what goes wrong, and how we fix them.
IN THIS GUIDE
01
What Mason Checks
How Joist Hangers Hold Your Deck
JOISTS
The boards that hold up your deck floor.
HANGERS
Metal brackets at each end of a joist.
EVERY HOLE
Each hole gets the right fastener.
Joists are the boards that hold up your deck floor. At each end, a joist sits in a metal joist hanger.
The hanger is fastened with the right nails or screws in every hole. That’s what lets it carry the load.
Hangers are often installed with missing nails, the wrong nails, or none at all.
Mason’s diagram: joists sitting in metal hangers under the deck
An empty nail hole is a missing piece of your deck’s strength.
02
Warning Signs
Signs Your Hangers Are Failing
RUST
Rusty or flaking hangers.
EMPTY HOLES
Missing nails or empty holes.
A DIP
A low spot in the deck floor.
Outdoors, rain and treated lumber can slowly rust the metal away.
As the hanger weakens, the joist can slip or drop. The floor sags, and the whole deck loses strength.
Check this today
From under the deck, look at the hangers with a flashlight. Every hole should have a fastener, and the metal shouldn’t be flaking.
03
How We Fix It
An Afternoon Now, or a New Frame Later
We inspect every hanger under the deck. Rusted or loose hangers are replaced with new coated ones, and every hole gets the right fastener, the way the manufacturer requires.
Caught early vs. caught late
Caught early, it’s an afternoon of work. Caught late, it’s a new deck frame.
In Northern Virginia
Fairfax County’s deck guide requires hangers deep enough for the joist (at least 60% of its depth) and installed without bending the flanges. Every deck in Fairfax County needs a building permit. We fixed this on our White Birch project in Fairfax.
Planning a bigger project?
Building a new deck? We use coated hangers and the right fastener in every hole. See prices and real projects on our deck and outdoor living page.
What goes wrong: a fully nailed hanger vs. one with missing nails
ASK MASON · DECK
Want to know another problem?
SPOTTED ONE OF THESE SIGNS?
We’ll check it before it turns into a big repair
Free in-home visit from a Class A licensed team. We check the problem and the rest of your deck, then give you a clear written plan.
ABOUT THE AUTHOR
The Great House team
Written by the team at The Great House LLC, a Class A licensed builder and remodeler in McLean, VA (License #2705197237). We have renovated 30+ Northern Virginia homes since 2022.
PLANNING A PROJECT?
Our deck and outdoor living service
See prices, real photos and how we work: our deck and outdoor living page. Real projects: our project gallery.
Serving McLean, Vienna, Great Falls, Fairfax, all of Northern Virginia.