What is the purpose of a rim joist?

In the framing of a deck or floor system, a rim joist is attached perpendicular to the joists, and provides lateral support for the ends of the joists while capping off the end of the floor or deck system.

What is rim joist on deck?





Rim joists are the perimeter joists of a deck. The two outside parallel joists, plus those that run perpendicular to all the joists, form the rim of the deck or a band that ties the structure together. Hence, they are known collectively as band boards and rim boards.

Is rim joist necessary?

Yes, if your framing a house or a deck you’ll need a rim joist. They create the edge of your floor framing and close off the open edges. For example, if your framing a 10×10 deck off the back of your house, you’ll probably be using 2×8 or 2×10 joists spaced 16 inches on center.

Can you drill through rim joist?

Since the rim joist is continuously supported by the walls or foundation it rests on, the strict notching and hole-boring rules don’t apply. Just don’t create a large hole or notch directly under a group of studs that support the end of a beam, or a window or door header above.

How do you support rim joists?

Step 1: Attach Rim Joist



Measure and cut the rim joists to length. Set one edge of a rim joist on the beam with the top edge of the other end flush with the ledger. Fasten the boards with two 3-inch deck screws. Fasten the other rim joist the same way.

Is a rim joist load bearing?





The main job of a rim joist, also called a band joist, is to provide lateral support for the joists, to prevent the joists from leaning under the weight of the load-bearing walls resting on them. The rim joist also covers the ends of the joists to cap off the joist cavities, the open spaces between the joists.

Do rim joists need to be doubled?

It is advisable to increase the rigidity and strength of your deck’s rim or perimeter in order to reduce bounce and provide a solid foundation for your rail system. This can be accomplished in a couple of ways. You may want to install double rim joists across long sections to respond to the flexibility of the material.

Do you need joist hangers on rim joist?

When a beam supports the joists from below, securing the rim joist to the field joists with through screws will save time over using hangers. Also, in this situation hangers are redundant because the rim joist carries little weight. The main function of the rim joist here is to keep the joists aligned.

How do I attach deck posts to rim joist?

Quote from the video:
Quote from Youtube video: Use stainless steel fasteners 4×4 wood guard posts can be attached to the deck frame on the outside or the inside of the rim joist depending on your design. If your post is on the outside.

How much of a joist can be notched?



Maximum depth of notch of any joist in any situation is 35mm.

Can you cut a 4 hole in a joist?

The hole cannot be larger than one-third the depth of the joist, so the maximum hole size for a 2×12 joist (actual size 1-1/2 x 11-1/4 in.) is 3-3/4 in. diameter—plenty big enough for running cable! You can drill the holes anywhere along the length of the joist (first photo).