What Are Joist Hangers and How Do You Fit Them Properly?

 If you're building a deck, a shed floor or a loft frame, you'll need a solid way to hold your joists in place. Skew-nailing works in a pinch, but it's slow and the joint can loosen over time. That's why most builders use joist hangers instead.

What Are Joist Hangers?

Joist hangers are metal brackets that hold the end of a timber joist against another piece of timber, such as a beam, ledger or wall plate. The joist sits inside the bracket and is nailed in from the sides. This spreads the weight across the fixings and gives you a much stronger joint than nails alone.

Most are made from galvanized steel. The zinc coating helps stop rust, which is a big plus for decks, garden buildings and damp spaces like garages.

Where Does a Jiffy Hanger Fit In?

A Jiffy Hanger is a well-known timber-to-timber joist hanger. It's made from one piece of steel with no welds, and the strap is designed to be adjustable, so it works with a range of joist depths. You don't need special tools. A hammer and the right nails are enough.

That's why it's a favourite with DIYers as well as trade workers. It's cheap, simple and does the job well on floors, decks, pergolas and small extensions.

When Should You Use Joist Hangers Double?

Some jobs need more strength than a single joist can give. Think of a floor that carries a bath, a wall sitting above, or the edge of a stairwell opening. Builders often fix two joists side by side to handle the load.

For that, you'd use joist hangers double, which are made to hold two pieces of timber in one bracket. Don't squeeze doubled timber into a single hanger. It won't sit properly, and it won't carry the load it should. Always pick the hanger that matches the width of your timber.

How to Fit Joist Hangers Step by Step

You don't need years of experience for this. Take your time and follow these steps.

1. Measure your timber. Check the width and depth of the joist so you buy the right size.
2. Mark the position. Use a pencil and a builder's square so every joist ends up straight and level.
3. Fix the hanger to the beam first. Nail through the holes on the back plate. Fill every hole unless the maker says otherwise.
4. Place the joist. It should sit snug in the hanger with no big gaps at the sides or bottom.
5. Nail through the sides into the joist. Again, use every hole so the load is shared properly.
6. Check it. Give it a firm push. There shouldn't be any movement or wobble.

Which Nails Should You Use?

This is where many people go wrong. Use short galvanized square-twist nails or the type the hanger's maker recommends. Standard wire nails can bend, and some screws are too brittle for this kind of load. Also, use galvanized fixings with a galvanized hanger, so the metals last equally well outdoors.

Common Mistakes to Avoid

• Leaving nail holes empty to save time
• Picking a hanger that's too big or too small for the timber
• Using the wrong nails or screws
• Fitting the hanger crooked, which puts the joist out of line

A Quick Word on Safety

For a garden deck, following the steps above is usually fine. If you're building a house floor, an extension or anything that carries serious weight, check your plans or speak to your local building control office first. It's much easier to sort this out before you start than after.

Final Thoughts

Joist hangers make timber framing quicker, tidier and stronger. A Jiffy Hanger is an easy choice for most home projects, and if your design uses doubled timbers, joist hangers double will keep everything lined up and sharing the load. Measure twice, use the right nails, and fill every hole. Do that, and your frame should stay solid for years.