How Many Strands Of Rail Cable Should I Use & How Far Should I Space The Posts?

Hey there! Let’s get your new rail past the strictest of inspectors.

Keep these two guidelines in mind and you should pass any inspection we have heard of, and we have heard of some doozies! One inspector hung a 40lb weight on our customers’ wire to see if it would deflect or make the spacing between the cables stretch beyond 4 inches. They passed by building their cable railing system with these two steps.

Rail Cable Spacing

A common question; how many strands of cable should I use? In general, for a 36-inch rail, you will want to use 11 strands of cable and 12 for a 42-inch rail.  Most building codes call for 4-inches of spacing with deflection.  Deflection is how much the cables will separate from one another under force.  You shouldn’t be able to push a 4-inch sphere through the cables.  We recommend spacing your lines 3 inches apart or less.  Check!

Post Placement

How far should my intermediate posts be from one another? The ideal distance between all your posts for Cable Railing is 4 feet.  The scenario above with the 40lb weight passed with 5-foot spacing, however.  The further you go from 4-foot spacing the easier the lines will deflect.  In some areas in States like Florida and California, 4 foot spacing between posts is part of the code requirements.  Imagine a 50 foot run of cables spaced at 3 inches apart with no intermediate posts.  You can imagine how easy it would be to separate the lines from one another no matter how tight the lines are.  The posts support the weight of the rail cable as well, greatly reducing the pressure the end posts and fittings have to sustain to maintain tension.  Our advice is to stay as close to 4 feet between posts as you can never to exceed 5 feet.  We always recommend checking with your local building code agency to confirm what the standards are for Stainless Steel Cable Railing in your area.

Enjoy your view AND your new Stainless Cable Rail!