What Is A Rim Joist

What Is A Rim Joist. Floor framing is often done using 2x or engineered timber, which includes plywood and OSB.

A plywood subfloor and completed flooring such as tile, wood, or carpet are used to cover the floor joists. 16″ on center is the most frequent spacing.

A sturdy wood band will run down the side of a home being constructed this is commonly formed of 2x material or engineered timber such as plywood and OSB. The rim joist is what it’s called.

What Is A Rim Joistrim joist

The purpose of this article is to explain what a rim joist is.

Working Rim Joist

Rim joists, or band joists, perform two primary functions they provide lateral support for joists by preventing them from tilting under the weight of the load-bearing walls.

The rim joist also caps off the joist cavities, or open spaces between the joists, by covering the ends of the joists.

Rim joists also offer a substantial mass of wood that is convenient for nailing external wall sheathing, siding, and trim boards.

Size And Material Of Rim Joists

The strength of your rim joist is determined by its size and the contractor you pick to construct it. Rim joists, like other types of joists, come in a range of diameters. A rim joist will never sag or droop in this manner.

We’ve created a lot of exceptions in the past. Floor joists can be even smaller than rim joists, therefore 2 x framing timber like 2 x 10s or 2 x 12s is commonly used for floor joists and rim joists.

TJIs, or engineered wood joists, are another option. Engineered and conventional lumber are used to construct many houses and buildings.

For the most part, we employ 2×12 rim joists with TJI floor joists. Every component of the frame will be accompanied by a blueprint detailing its specs and plans.


Is it necessary to pressure treat the rim joists?

The rim joist, which is placed above the cinder block or concrete foundation wall and produces the outside box of the floor, is one of the most significant pieces of a floor assembly.

The sill plate is responsible for ensuring that the rim joist stays on its intended path. Unfortunately, because this area of your property stands directly on damp ground, moisture may have found its way into your home in other ways.

If you use rim joists, do you need joist hangers?

Screwing straight through the rim joist into the supporting beam is usually faster and stronger than utilizing joist hangers in most circumstances.

Because beams typically carry greater weight than floor joists, the current screws may not be able to hold the increased load of a new beam across an existing one.

Rim the joists should be insulated?

Because they’re both above ground, rim joists should be insulated to the same amount as an above-grade wall.

Because you don’t want air leaks in your rim joist, only air-impermeable insulation like rigid foam or polyurethane spray, not fiberglass batt insulation, which might leak part of its trapped air through gaps in the wood should be utilized.

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