Deck railing

Deck railing is a guard rail to prevent people falling from decks, stairs and balconies of buildings. Over time, many different styles of deck railing have been developed.

The most common residential deck railing design is built on-site using pressure treated lumber, with the vertical balusters regularly spaced to meet building code. Cable railings typically use stainless steel cables strung horizontally. Glass balusters and glass panels open the view while still providing safety. With the increasing popularity of composite lumber for decking, manufacturers are providing composite railing components. Other options include wrought iron and sheet steel, into which custom designs can be cut.

Building code varies on the national, state, county and municipal level. Most areas in the world that use a variation of the International Building Code require a guard rail if there is a difference of 30" or more between platforms. Other common requirements are that no space on the railing be greater than that through which a 4" sphere could pass and that the railing assembly be able to withstand a load of 50 pounds per square foot.

The typical deck railing is generally built from pressure treated lumber. Posts on a deck are also typically pressure treated wood and standard sizes are 4x4, 6x6, and 8x8. These posts give structural support to the railing assembly and are the most critical part for the safety of the guard rail assembly. In between the posts, two 2x4s are attached to the posts with screws for the best connection. The lower board is placed 3.5" from the top of the finish deck to the bottom of the board. The top board is placed with the top at 35" from the deck. Then the vertical 2x2 pressure treated wood balusters are installed spaced regularly every 3.5". Then a 2x6 is installed horizontally across the top of the posts and to 2x4. The 2x6 should be fastened with screws to the posts and 2x4 boards for the most rigidity.

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Wikipedia