# How do you calculate stair carpet material.

## Recommended Posts

When I do a material list for the floor and I'm looking at my flooring take off I see my carpet and pad is only calculating the rooms and not the amount of carpet on the stairs. It does include the two stair landings as you go up the stairs, but not the tread or risers. I want to know how much carpet for the treads and risers also. How do you do that?

##### Share on other sites

The runner does show in the materials list, just not where you would expect, and it seems to calculate incorrectly.

You could write a macro to do the calculation as all the required info is available.

##### Share on other sites

I never calculate carpet on stairs.  But that's just because I hate carpet on stairs.

• 2
##### Share on other sites

Just as an FYI from a long time Flooring Industry Expert as you should never take the flooring takeoff for sheet vinyl or carpet too close to the takeoff amount.  Even though it may be 1000 square feet you may actually need 1400-1600 square feet as they come generally in 6' and 12' rolls and there is patterns to take into account and layout.

##### Share on other sites
5 hours ago, ChiefNICKELSON said:

When I do a material list for the floor and I'm looking at my flooring take off I see my carpet and pad is only calculating the rooms and not the amount of carpet on the stairs. It does include the two stair landings as you go up the stairs, but not the tread or risers. I want to know how much carpet for the treads and risers also. How do you do that?

For Carpet, add a runner. Then edit the components tab as shown

##### Share on other sites

It's a simple calc to do manually..... carpet is sold/quoted by the sq ft but in reality it is costed as a broadloom ie width of the carpet....

This is why sq ft is generally useless to calculate carpet quantities.

Carpet is usually 12ft wide (3.66m).... and the stairs are usually 4ft wide or less (except for winders but I will come back to that)... so... because 12 (ft) can be divided by 4 (ft) 3 times, to find the amount of broadloom we want we take the total length of all the steps and divide it by (in this case) 3 to get 3 equal strips.

We are using a 1/3rd width.... or to put it a simpler way, cut a 10ft long broadloom up into 3 equal (4ft wide) widths and you get 3 x (4ft wide) x 10ft   long strips/runners'

To work out how much you need on a stair case, it's simply a matter of using the above to do a simple calc.  Add the length up the riser and along the run with some wastage trim eg 1.6ft in length for each step multiplied by the number of steps and then rounded up to a multiple of 1.6ft....

like this.........1.6ft x 10 steps = 16ft, divide by 3 (1/3rd width) = 5.3ft of BROADLOOM carpet.  Now, if you go back to the idea of cutting it into strips, you will see that you are only getting 3 x 5.3ft long strips which is only enough to do 9 as the last step is spread across the broadloom (5.3ft / 1.6 = 3.5 or 3 and a half steps in length).  To enable four steps you either need some wastage elsewhere or increase the broadloom length from 5.3ft to 6.4 ft (1.6 x 4), which if you are following the maths you will see allows 12 steps total now.

For landings you just treat them as another step and work out how long the rise/run is and add it into your calcs.

For winders, you take the longest points for length and if they are over 4ft wide then instead of doing a 1/3rd width you do a half of 12ft which is a half width and follow the same process as above just for those winders....

Simple!

As an aside, I recently had a flooring company try to 'overquote' my client (who was making the mistake of shopping and only focusing on price per sq ft) by telling them they needed more sq footage than was required (as not many people can plan out a house full of broadloom carpet).  It got down into an argument as the retail outlet were adamant the quants were correct and my client should pay \$780 more.  That extra carpet was never going to be supplied.... the extra footage is fictitious and just means the true sq ft price is higher... The client didn't understand the principle involved so in the end I laid out the entire job for the client and installer.... they saved \$780 and my name is mud with the retailer..

• 1
##### Share on other sites

Setting proper pattern match and efficient material usage aside for a moment, here are my quick pieces of advice:

1. Yes, you can use a Runner but that has some notable issues.  First off, it doesn't give you a proper total in the material list. To get usable information, you would have to customize your Component information for each and every set of stairs you build.  And even then, this method won't work for winders, flares, starter treads, or other non continuous width stair designs where you want carpet on the whole step.
2. To get a more accurate result that doesn't need to be customized every time, you can use the steps Collection.  This method requires some pretty custom coding to parse and combine the information, but is far more accurate and can be added to the stair Components in your Defaults.
##### Share on other sites

The VERY simplest way to get this material takeoff is to forward the plan to the supplier. They'll gladly do it for free!!

• 1
##### Share on other sites
2 hours ago, robdyck said:

The VERY simplest way to get this material takeoff is to forward the plan to the supplier. They'll gladly do it for free!!

Why? You place yourself in the same position as my client of being ripped off because someone doesn't know/understand how to do a quick calc?

##### Share on other sites
19 hours ago, rgardner said:

Just as an FYI from a long time Flooring Industry Expert as you should never take the flooring takeoff for sheet vinyl or carpet too close to the takeoff amount.  Even though it may be 1000 square feet you may actually need 1400-1600 square feet as they come generally in 6' and 12' rolls and there is patterns to take into account and layout.

Yes I agree. I do add waste for it, but primarily use this information as a starting point to convert it to square yardage. Then I use it to build allowances and to pass on to our carpet vendors who come and do final take off before ordering.

##### Share on other sites

Thank you guys I was able to use a runner and change the components to list is correctly in my material list. I have the carpet runner and ID for flooring. Although the calculation of the area of the carpet on the stairs doesn't calculate correctly. Still discovering how to use, even create macros for calculations. Any tutorials on how to develop them?

##### Share on other sites
On 5/27/2021 at 11:18 AM, ChiefNICKELSON said:

When I do a material list for the floor and I'm looking at my flooring take off I see my carpet and pad is only calculating the rooms and not the amount of carpet on the stairs. It does include the two stair landings as you go up the stairs, but not the tread or risers. I want to know how much carpet for the treads and risers also. How do you do that?

To many times lately people stray from their lane. This is an example. Send your plan to a carpet guy or two and get the correct answer.

##### Share on other sites
49 minutes ago, raltd9245 said:

To many times lately people stray from their lane. This is an example. Send your plan to a carpet guy or two and get the correct answer.

Some of us like to avoid having to get our subs and suppliers to do takeoffs every time we want a rough estimate.  It adds up to an astronomical number of man hours, adds extra steps, adds to the timeline, introduces an increased chance for miscommunication, etc.  In at least the early phases it can be far more efficient to tabulate all those quantities ourselves.

##### Share on other sites

Last time I did quick calcs for stairs I think we used 2.5sqft per tread and 2sqft per riser. 9sqft per landing if the stairs are 36" wide. Add all that and add 10% for a guestimate.

##### Share on other sites
3 hours ago, raltd9245 said:

To many times lately people stray from their lane. This is an example. Send your plan to a carpet guy or two and get the correct answer.

Really?  If you are taking the time to provide quantities then it is not all that hard to gain a basic understanding of how to calculate that which you are providing..... either that or don't provide it....