Replacing your old wood railing with a cable railing can really open up your view. Wood balusters are visually obstructive and can make enjoying the view from your deck more like trying to see a movie when the guy seated in front of you is 6 foot 7. Cable railings are becoming popular since the cables provide a safety barrier but with the least visual mass, in many cases almost disappearing from your view.
The main things to consider are:
1. Building code requirements.
2. Understanding the importance of structural rigidity in the post system.
3. What type of posts / frames to use and where to purchase them?
4. Which cable / fittings to use and where to purchase them?
5. Installation, do you hire a contractor to install the railing or DIY?
Building Codes:
Cable railings are allowed by building codes in most areas of the US. In many areas, if the rail is over
30 "off the ground, it must be at least 36 inch tall. In a few townships, it must be 42 inch tall. Cables
must be spaced and tensioned to prevent a 4 inch ball from passing through any opening. You should contact your local building code enforcement office (before buying the materials). to make sure any local code revisions are understood.
Structural rigidity:
A cable railing differs from a standard wood spindle railing in that the cables need to be tensioned quite a bit to meet the 4 inch ball code requirement. This places a lot of force on the end posts. For wood spindles it may be OK to have a 3-7 / 8 inch space between spindles but for cable, cable deflection must be
considered. It is not practical to tension the cables so that they would be impossible to deflect so most
cable railing manufacturers recommend a 3 to 3 1/4 inch space between the cables.
In a cable railing system, the end and corner posts have to be able to handle an enormous amount of force. The combined tension of all the cables can equal the weight of a small car. It is very common that an amateur cable railing designer / builder fails to understand the forces involved and how to safely counter
act them. Seek help from someone with proven experience here or your railing can end up failing your
building inspection and be very costly to rectify.
POSTS / FRAMES:
There are basically three types of material suitable for cable railing posts: metal, wood and concrete.
Note: Composite lumber is not strong enough to be used for cable railings.
Here are the main types of posts and some things to consider:
– WOOD:
Wood posts can be a good option for rustic style homes. Wood is more visually bulky than metal however so it may not be the best choice where a preserving your view is the primary concern. Wood is a good option for the budget minded as it is fairly inexpensive and can be cut and drilled with inexpensive tools. A
drill press is advisable for drilling holes straight through the post. This is pretty important since you
will be drilling hundreds of holes and if you get one crooked, it will change the "visual line of the cables" and make the whole job look sloppy. Some cable fitting manufacturers offer a drill guide to aid in
this. Wood siding is not suitable for an end post unless there is significant wood blocking behind it and
long lag screw fittings are used.
Many people elect to use one of the exotic (outdoor hardy) hardwoods like IPE (ie Brazilian Walnut,
Pronounced e-pay). These species hold up great outdoors but are really hard to cut, drill, rout etc. You
may need to upgrade to professional grade tools to get through this job.
– Metal:
Metal posts come in a wide array of styles to match your homes architectural style. Metal posts, due to
there high strength, have the least visual mass of the post types are usually the choice where the view is
of primary importance. Metal posts can be purchased directly from manufacturers over the web or you can hire a custom fabricator to build the railing on site (most expensive option). One concern with site built metal railings is that it is difficult to properly finish a railing outside of a controlled factory
environment. Prefab posts are often powder coated and sometimes galvanized and powder coated (for ocean front locations). Metal post systems are usually designed to easily be installed by a contractor or handy DIY type.
– Concrete:
Concrete can be used as an end post where there is a column or wall that is made of it. Usually the
intermediate posts are made of another material, metal or wood. Do not attempt to mount to stucco over wood as the cables will pull it right off. Understanding the construction of the post is essential.
Cables and Fittings:
Cables and fittings come in a enormous array or types and styles. Seek some advise from one of the
cable / fitting suppliers you can easily find on the web. For ease of installation, look for quick lock
fittings (swage less fittings) otherwise you will be crimping on site which adds a lot of work and
requires special tools. Some companies supply both the posts and the cable / fittings in kit form which
takes the guess work out of process.
Installation
Installation is fairly simple if your handy. A typical deck rail can be installed by a couple of people in
a weekend. When your done, you can sit back enjoy your beautiful view.