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Measuring carpet length to fit 14 stairs requires experts; it is not a recommended DIY project. Furthermore, stair carpet fitting requires more than basic mathematical knowledge; the details that go into the process can overwhelm an amateur. That said, it would not harm you to take the measurements and learn the trade in your free time.
Stairs come in many shapes and sizes. Carpet measurements to cover different variants of stairs differ. You might get a higher quote for a Hollywood stair case than you would for a box stair case. The design dictates the number of square feet of carpet that will cover a portion of the tread or the stringer length of your stairs.
How to Investigate Stairs for Carpet Fitting
Many terminologies go into the simple measurements that decide the length of a carpet to fit the entire staircase. However, inches are the standard measurements for any side of a staircase.
Let’s consider the tread section, which is the point you stand on while going up a flight of stairs. Many homes and buildings have a standard set at 10 inches deep. You must take measurements to confirm your stairs conform to this.
If you have walked up a staircase and bumped your foot on a staircase, then you probably did that on the riser. The riser is typically 8 inches high. Again, take measurements to confirm.
Knowing the wording that goes onto the various sides of a staircase is just one part of the task. You must consider the design, shape, and material used to make your stairs. The box stair is one of the most common; it has no fancy designs and takes in a fair amount of carpet compared to others.
The surface of the box stair is usually 18 inches, accounting for the risers and treads. For the correct carpet size, take 18 inches and multiply by the entire width of the stairs—about 36 inches. Multiply the results with the total number of stairs, in this case, 14, the final figure is what you present to your carpet installer for fitting.
Typically, most stairs have more risers than treads. Consider this when computing how much carpet you need for 14 stairs. Here is an example of the total carpet size for 14 box stairs.
Multiply 36 inches of width by 18. Computing with a calculator gives 648 inches. Multiply 648 by 14, which is the total number of stairs. The answer is 9072 square inches. The square inches equate to 63 square feet of carpet size.
If you do not fancy the complexity of a fixed carpeted staircase in your house, there are options like the Westerly 25' Stair Runner Rug, which is 25 feet long and 26 inches wide. You can easily fit the carpet on your 14 stairs by taping it down on the treads. Here is an Amazon review of the rug.
Pie stair measurements differ from typical box stairs. They are fancier. If you have them fitted, you will need to take extra measurements to cover poles and windings.
Stairs of this nature demand a carpet whose grain aligns from stair to stair for a better finish. For ordinary pie stairs, measurements of about 40 inches by 30 are enough even for the winders. The size helps the installer to maneuver the piece until it fits.
Here is how to determine the measurements of pie stairs conjoined with cap stairs.
Measurements for box stairs, minus the noses, are easier to tabulate, but considering that most pie and cap stairs come with noses, you might have to consider an additional three inches for every 18 for the treads.
For the same number of cap stairs, which is 14 and includes a railing at the bottom or whichever side. The stairs will typically have a 90-degree winding turn. The curve is a design that opens at either end and narrows in the middle of the stairs. The curvy design means that the last three pieces of a cap stair are pie pieces. Here is how to tabulate carpet size for such a system.
For the pie stair section, plan for a 48-inch by 30-inch carpet size, which gives 1440 square inches. Multiply the figure by three. That totals 4320.
Carpet measurements for the 11 cap stairs, each covering 48 inches wide, having an 8-inch riser, a 3-inch nose, and a 10-inch tread. Require separate tabulations.
Part 1: Add the 8-inch riser to the 10, giving 18. Multiply 48 by 18 by 11, this gives 9504.
Part 2: Multiply 48 by 3 by 12 inches. This equals 1728 square inches.
Part one and two added together give 11232 square inches.
Finally, adding 11232 (Cap stairs) +4320(Pie stairs) equals 15552 square inches or 108 square feet of carpet needed.
Hollywood stairs are a common-sight in many homes nowadays. Ordinarily, they do not have a backing like most stair designs do. Therefore, they do not require a carpet.
But the carpeting decision is up to you. For a start, the stairs need about 20 inches of carpet. The steps also take in a lot of carpet length. They will take you about two times the length of the step, important for cover around the windings.
At the bottom of most stairs is a bullnose stair. The part demands a specially cut carpet because it is wider than the rest of the stairs.
Risers and treads in this section require no more carpet than an ordinary box stair would, but the outer edges demand more. The edges are bigger than those of box stairs, meaning the carpet size of the largest stair will help wrap around the section for a better finish.
Some other stair issues that might concern you are the noses of the carpet. The parts traditionally extend over the riser during installation. Typically, you will need extra inches beyond 18 that cover the step, and about three inches to solve the overhang issue in the noses.
The methods discussed here can give you the best estimate for tabulating typical stair sizes. However, if you are not an expert in the field, look for experts to help complete the task. Stair carpets are not only decorative but are essential safety additions to wooden or metallic stairs.