Windows Support Systems
Frequently Asked Questions
(Q) What types of Cable Support Kits do you have available?
(A) Window Support Systems products can fit any bay or bow window, with options to customize a kit to your specific needs.

    Our Cable Support Kits fit bay or bow windows designed to allow a cable to run down the inside of the mullion and hold at the bottom. We offer these kits in both the Straight Line Clamp and Lo-Profile Cleat versions.

    Our Cable Adjustment Arm Kits fit bay or bow windows which use threaded mullion rods in their assembly. Our product adds support by attaching to the top of these rods. We offer the Cable Adjustment Arm Kit in both the Straight Line Clamp and Lo-Profile Cleat versions.

(Q) How many support options are available for connecting a cable from a bay or bow window to the main structure?
(A) The options listed below are ranked on their combination of: a) strength and b) speed of installation, from most effective to least effective:
  1. Window Support Systems Straight Line Clamp: Holds up to 1,500 lbs. per cable without any cable slippage.

  2. Window Support Systems Lo-Profile Cleat: The cable locks up after moving less than 3/16" during installation, and holds up to 1,000 lbs. per cable.

  3. Eye screw with chain or cable: Begins to fail with a weight load of less than 172 lbs.

  4. Four-finger marine cleat: Begins to fail with a weight load of less than 151 lbs.

(Q) What is “zero slip” and why do I need it?
(A) Cable slip is a condition that occurs, in most cases, after window installers have left the job site. The problem exists with lacing-style cable cleats, in which the cable is hand-wrapped around extending lugs and must be pulled tight to “lock up.” It takes a window’s load of several hundred pounds to fully tighten a cable around these cleats – which can occur days or months AFTER installation, a time during which your window is not totally secure. In testing, this cable slip has ranged from 5/16” to over 1” and beyond.

That’s why our patented Straight Line Clamp, which clamps the cable secure from day one and features zero slip, is so crucial to maintaining ultimate window support.

(Q) What is a Cable Adjustment Arm and why is it better than using a turnbuckle?
(A) The standard turnbuckle has been around forever, used on everything from horse-and-buggies to classic screen doors. It’s great for adding tension to a chain or cable, but testing has proven that turnbuckles do not have the strength to hold a heavy bay or bow window. And, when adding normal vibration, they will “back off” within days of installation – allowing the window to sag. The Cable Adjustment Arm was designed to correct these flaws. It’s rated to over 1,500 lbs. of support, where most turnbuckles are lucky to support 400 lbs. In addition, the Cable Adjustment Arm is not affected by vibration, is easier to adjust and designed to work in limited-clearance installations. The turnbuckle simply features outdated technology. The Cable Adjustment Arm is clearly superior, offering total support and convenient installation.

(Q) Why are your kits the best?
(A) Cable Support Kits are all we do. We have invested years of research and testing into designing the strongest, most reliable Cable Support Kit ever. We’ve also taken the lead in addressing the industry’s pressing concerns around safety and installation ease. All of our kit components are independently tested – including long-term analyses— by highly qualified companies such as Architectural Testing, Inc.

In addition, Window Support Systems has implemented a supplier quality program that is in compliance with the Andersen® Corporation “Quality Program.” Every kit will reach the job site complete and ready for fast, streamlined installation— resulting in unparalleled window support!

(Q) What are the differences between your Straight Line Clamp and your Lo-Profile Cleat?
(A)Both are highly engineered, patented devices. Our Straight Line Clamp has set a new industry standard in that it will hold 1,500 lbs. per cable with zero slip. It requires no wrapping of the cable— you just pass it through the center of the device and tighten the clamp screws. Major window manufacturers such as Andersen Corporation®, Marvin Windows and Doors® and Pella Corporation® are featuring the Straight Line Clamp in all of their cable support kits.

The Lo-Profile Cleat, with its patented cross-lock feature, eliminates the need for additional fence staples or wire clamps. After lacing, the cable is run through a cross hole at the end and pulled tight. This cross-locking feature reduces slip, making the Lo-Profile the best lacing-style cleat available. It is rated at 1,000 lbs. of support per cable, easily outperforming all other cleats— and can be the perfect support device for lighter, “economy” windows.

(Q) What’s wrong with the other kits on the market? Why should I go with a Window Support Systems kit?
(A)Independent tests have proven that other kits fall far short in offering long-term reliability. When you take into account the weight of the windows themselves, plus vibration from storms and increasing vehicle traffic, it is more important than ever to have reliable support. Window Support Systems kits give you the uncompromised strength, safety and reliability needed under all conditions. Check out the Slip Comparison Chart and Test Results Comparison to see the results for yourself!

(Q) How do I make sure my new bay or bow window has a Straight Line Cable Support Kit?
(A)Most major window manufacturers in North America are now using a Window Support Systems Straight Line or Lo-Profile Cable Support Kit. Check out our "Who's Using Our Products?" page to get a partial list of the quality window manufacturers who feature our support kits. If the company making your bay or bow window is not listed on this page, be sure to specify the kit you want when ordering your window. Do not accept a substitute! Your bay or bow window needs the total support our kits provide.

(Q) Are your Cable Support Kits hard to install? Are there instructions?
(A)In addition to offering unmatched performance, Window Support Systems kits are easy to install and can be finished in minutes— saving valuable time on the job site. They come with detailed instructions, which will be included with your window. Instructions can also be printed from this website.

(Q) Why is "Made in USA" important to homeowners and builders?
(A)We strongly believe that the quality of our American-made kit components is higher and more consistent than that of competitive offerings that are imported – predominantly from Asian countries. It is not worth the risk of diminishing the performance of your new bay or bow window (and the value of your home!) just to save a few pennies.