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Reinforcing Deck Rim or Band Joists

It is recommended that the rigidity and strength of the rim or perimeter of your deck design be increased in order to lessen the amount of bounce and give a stable foundation for your railing system. There are a few routes that one can use to reach this goal. In order to accommodate the pliability of the material, it is possible that you will need to install double rim joists across lengthy areas. In addition to that, make use of the additional resources you have by placing blocks all the way around the perimeter. Because there is a greater chance that individuals would flock toward the edges of decks and the weight is less equally distributed over the frame, the edges of decks are more likely to bounce. This is because the weight is more concentrated in some areas. In addition, the railings are joined to the frame of the deck around the perimeter. The frame of the deck will be strengthened all the way through by using joist spacing of 12 inches on center.


Method 1: Through Screwing

When a beam supports the joists from below, it will take less time to use through screws instead of hangers to connect the rim joist to the field joists. Also, hangers aren't needed here because the rim joist doesn't carry much weight. The main job of the rim joist in this case is to keep the joists in line with each other.


Read more: Deck Joist Cantilever Rules and Limits


Pull and mark the joist layout on the inside face of the rim joist, as shown in the photos below. Then, extend the layout lines down the face of the rim joist and over the top. Mark which side of the line the field joist is on, and then start a 3-inch screw in the field joist to connect the rim joist to it. If you're working by yourself, start this screw in the middle so you can hold the rim joist and keep it balanced while you put it in. With one hand, line up the top of the field joist and drive the screw to hold the rim joist in place. Align the field joist with the layout mark you made on the inside face. Then, use two more fasteners to permanently attach the rim joist. Then, line up the rim joist with the rest of the field joists and secure it to them with through screws in the same way.


1. Measure and mark the joist layout on the rim joist, making sure to show which side of the mark the joist will fall.


2. Use a square to extend the layout marks across the face and top of the joist.


3. Start the first screw near the top of a middle joist based on the layout marks you made on the face.


4. Align the rim top to the joist and fasten it to the joist with a screw.


5. Fasten the rim joist permanently to the joist with two more through screws.


Method 2: Installing Hangers


If it's not easy to stand on the outside of the rim joist to through-screw the fasteners, it's a good idea to put hangers on the rim joist before putting it in place. With this method, it's important to make sure the layout is as accurate as possible and that the height of the rim joists doesn't change by more than 1/16 inch. To install the field joists this way, start by pulling the layout across the inside face of the rim joist and marking the side of the layout where the field joist falls. Use an end cut that is the same size as the joist to get the joist hanger to line up with the plan. When the top of the end cut is even with the top of the rim joist, drive the hanger's tab to hold it in place, and then drive 114-inch nails into the hanger holes to secure it. Install all the hangers according to the plan, and then install the rim joist by fitting the field joists into the hangers.


1. Pull and mark layout across the face of the rim joist using a square to extend the lines from top to bottom.


2. Align a joist hanger with a scrap of lumber to the layout lines and flush with the joist