FHB Logo Facebook LinkedIn Email Pinterest Twitter X Instagram Tiktok YouTube Plus Icon Close Icon Navigation Search Icon Navigation Search Icon Arrow Down Icon Video Guide Icon Article Guide Icon Modal Close Icon Guide Search Icon Skip to content
Subscribe
Log In
  • How-To
  • Design
  • Tools & Materials
  • Restoration
  • Videos
  • Blogs
  • Forum
  • Magazine
  • Members
  • FHB House
  • Podcast
Log In

Fine Homebuilding Project Guides

Framing

Guide Home
  • Introduction to Framing
  • Framing Tools, Techniques, and Materials
  • Framing Floors
  • Framing Walls
  • Framing Stairs
  • Framing Roofs
  • Efficient Framing Methods
  • Timber Framing
How-To

2 Rules for Building Comfortable Stairs

As the rise goes down, the run needs to go up correspondingly, or vice versa.

By Michael Maines
  • X
  • facebook
  • linkedin
  • pinterest
  • email
  • add to favorites Log in or Sign up to save your favorite articles

On the first stairs I built, I sized them for a 1×8 riser and a 2×8 tread. The result was a disastrously uncomfortable stair, with treads too short for adult feet.  Although the rise itself wasn’t terrible, something about using it felt very cramped, and I set out to find what went into a safe, comfortable stair. Since then, I’ve built and/or designed many stairs, and every time I think about the lessons I learned on that first one.

For anyone not familiar with the terms, “Rise” refers to the vertical distance from the top of one tread to the top of the next tread. It also happens to be the dimension of one of the cuts on each of the actual stair stringers–the framing members that hold up the stair treads. The “Run,” however, seems to cause some confusion. It’s the horizontal distance from the face of one riser to the face of the next riser, or from nosing to nosing, and the other stringer cut—it’s NOT the size of the tread itself, which includes a leading edge overhang of ¾” to 1 ¼” (according to the IRC for most residential stairs).

The IRC (International Residential Code) calls for a maximum rise (“r”) of 7 ¾” and a minimum run (“R”) of at least 10”. They use the term “tread” instead of “run” but I think that’s the cause of some confusion, so I’ll use the standard term “run.”

IRC code limit stair: rise r ≤ 7 3/4" run R ≥ 10" r+R = 17 3/4" (good) 2r+R = 25 1/2" (within range) → stair will be comfortable
IRC code limit stair:
rise r ≤ 7 3/4″
run R ≥ 10″
r+R = 17 3/4″ (good)
2r+R = 25 1/2″ (within range)
→ stair will be comfortable

Rule one says that rise plus run (r+R) should equal 18 inches. Why? That’s what most people find to be a comfortable stride on most stairs. You can cheat a bit up or down, but below 17” and more than 19” will result in steps that require strides either too big or too small for most people. On my first stair, r+R was roughly 15 inches—way too far from 18” to be comfortable or safe. The IRC limit gives an r+R of 17 ¾”—pretty darn close to 18.

I relied on the 18” rule for several years, until I met another carpenter who insisted that a better measure was that twice the rise plus (2r+R) the run should be 25 inches. After trying to decide which rule really was better, I settled on the idea of using both. If a stair meets both numbers, it will be comfortable. If it meets only one of the numbers, it will be less comfortable. If it meets neither number, it will not be comfortable.

My first stair had a 2r+R of about 23. The IRC limit gives a 2r+R of 25 ½”. My ideal stair has a 7” rise and an 11” run. I usually end up having to squeeze the stair for one reason or another, but on the rare occasions I can include a 7-11 stair, it ends up being very comfortable. I call it a lazy stair, because it seems to take no effort to use (but you still feel like you’re getting somewhere). Its r+R is 18” and its 2r+R is 25”, right where they should be.

The Perfect Stair (in my opinion): rise r = 7" run R = 11" r+R = 18" (perfect) 2r+R = 25" (perfect) → Stair will be comfortable
The Perfect Stair (in my opinion):
rise r = 7″
run R = 11″
r+R = 18″ (perfect)
2r+R = 25″ (perfect)
→ Stair will be comfortable

You have probably had the experience of using stairs, often in an institutional setting, that felt ridiculously shallow, possibly even requiring stutter steps, or inducing the strong desire to take two steps at once. A not-too-extreme example of that would be something like a 4” rise and a 14” run. That would give an r+R of 18”, right on the money for stride length. But 2r+R is only 22”, pretty far from 25”, and results in the stairs feeling like you need to take them two at a time, or that you are shuffling up them one step at a time.

Shallow stair example: rise r = 4″ run R = 14″ r+R = 18″ (perfect) 2r+R = 22″ (too low) → won’t be comfortable
Shallow stair example:
rise r = 4″
run R = 14″
r+R = 18″ (perfect)
2r+R = 22″ (too low)
→ won’t be comfortable

Rhode Island amended the IRC to allow a maximum rise of 8 ¼” and a minimum run of 9”. With an r+R of 17 ¼” and a 2r+R of 25 ½”, both numbers are close enough to the ideal to be comfortable for most people. On the ProHOME, Mike Guertin used Rhode Island’s amendment to his advantage. I had designed the stairs with a 7 7/16” rise and 10” run (r+R≈17.5”, 2r+R≈25”, good numbers). Mike was able to eliminate a tread and riser and use the headroom gained to create more floor space and an interesting nook in one of the bedrooms, using a rise of 8” and a run of 9 ¼”, for r+R of 17 ¼” and 2r+R of 25 ¼”, well within the comfort zone.

Mike Guertin’s ProHOME adjusted dimensions: rise r = 8″ run R = 9 1/4″ r+R = 17 1/4″ (good) 2r+R = 25 1/4″” (almost perfect) → stairs will be comfortable
Mike Guertin’s ProHOME adjusted dimensions:
rise r = 8″
run R = 9 1/4″
r+R = 17 1/4″ (good)
2r+R = 25 1/4″” (almost perfect)
→ stairs will be comfortable

What if situation allowed for keeping the maximum rise of 8 ¼” and we expanded the run to 10 1/2”? Then r+R would be 18 ¾”, acceptable, but 2r+R would be 27”, which is more than ideal. Very tall people may find stairs with those dimensions comfortable, but the vertically challenged among us would not. How about a minimum run of 9 ½” but keep the riser down at 7”? 2r+R would be 24 ½”, pretty good, but r+R is only 16 ½”, not enough, and the stair would feel diminutive.

staircase staircase with storage

Here’s a good example of a stair I don’t think anyone would mistake for being comfortable. I designed and built it many years ago, but recall using a stepladder for dimensional inspiration. Aside from the treads being too small for safety, the rise would have been about 12” and the run about 4”. The r+R, then, was 16” (too low) and 2r+R was 28” (too high). Fortunately, the stair is used primarily for storage.

Steep stair example: rise r = 12" run R = 4" r+R = 16" (too low) 2r+R = 28" (too high) → won't be comfortable
Steep stair example:
rise r = 12″
run R = 4″
r+R = 16″ (too low)
2r+R = 28″ (too high)
→ won’t be comfortable

 

To summarize:

The rise plus the run (r+R) should be within an inch of 18”.

Twice the rise plus the run (2r+R) should be within an inch of 25”.

Break those rules at your own risk.

Molasseskat commented with a good idea; here is a graph that shows what I consider the “sweet spot” for stair design. I included icons for each of the stairs described in this article:

Graph that shows the "sweet spot" for stair design

More great stair-building articles:

stair stringers
How To Assemble Deck-Stairs
Laying Out Basic Stair Stringers – To ensure level tread cuts and plumb riser cuts on stair stringers, it’s crucial to get the layout right. Deck-Stair Layout 101 – Deck stair layout is simple, right? Probably right, unless it’s the first time you’ve tackled the task. With numerous “stair calculators” available, figuring rise and run dimensions is easy. Applying those dimensions is another matter. Watch this tutorial to see how to layout a basic set of deck stairs.
Lay Out Accurate Stair Stringers With This Custom Tool – If you’re framing a staircase, you could hope that the stair gauges on your framing square bear against the edge of a nice straight board, but they might not—in that case there’s a better way. Watch this video to learn how to lay out accurate stair stringers. Framing a Staircase – Regardless of the method you choose, every set of stairs requires the same basic approach to get from one floor to another safely, comfortably, and legally. In this photo slideshow, Fine Homebuilding author John Spier takes you through the steps of framing a staircase.

 

Fine Homebuilding Recommended Products

Fine Homebuilding receives a commission for items purchased through links on this site, including Amazon Associates and other affiliate advertising programs.

Original Speed Square

A Speed Square or rafter square can help you cut rafters, measure angles, and accurately guide your saw for straight and angled cuts. It's a must have.
Buy at Amazon

Code Check 10th Edition: An Illustrated Guide to Building a Safe House

It would be great if this book didn’t need to exist, but it's definitely a must-have. It's a one-size-fits-all code book that's easy to understand and will help you sail through your inspections.
Buy at Amazon

11" Nail Puller

Pulling nails is a part of framing, so this tool is always on our belts — the cats paw makes the job easy, plus the company donates to veterans.
Buy at Amazon
Previous: Calculating Stairs Next: Laying Out Basic Stair Stringers

Guide

Framing

Chapter

Framing Stairs

Sign up for eletters today and get the latest how-to from Fine Homebuilding, plus special offers.

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

View Comments

  1. molasseskat | Sep 22, 2016 02:09pm | #1

    It might be best described using a graph of run vs. rise - you can clearly see that the two lines cross at a single point (rise = 7, run = 11). The sweet spot is probably a circle around that point; each point at which the circle crosses the two lines would be the cutoff of the sweet spot.

  2. austinindian | Mar 15, 2017 01:40pm | #2

    My architect has done drawing for our stairs and they now stand at Rise 7 3/8" - Run 11". I'm pushing for 7'' - 11'' but there are consequences..more floor space needed. I'm curious what is meant by the words "squeeze the stair" in this article. Can someone further explain?

  3. Mike_Maines | Mar 15, 2017 03:50pm | #3

    Molasseskat, I'm sorry I missed your comment (six months ago!) but I thought you had a great idea so I created a graph. It turns out it's not a circle but a parallelogram, at least using my rules of thumb. It may be a little busy but the yellow area represents a stair that most people will find comfortable. Outside of the yellow zone represents a stair that most people will find uncomfortable in some way.

  4. Mike_Maines | Mar 15, 2017 04:04pm | #4

    Austinindian, the rise and run your architect designed is well within the comfort zone, though a run of 10 1/2" might be slightly more comfortable.

    By "squeeze the stair," I mean that on my jobs space is usually at a premium, so we cheat the stair to be steeper than ideal, often with code-minimum 10" Run and approaching the code-maximum 7 3/4" Rise.

    In your case, if you'd like a shallower but still-comfortable stair, you'll need to add one or more risers to what is currently designed, then adjust the tread depth (aka Run), staying within the yellow zone on the new graph at the end of the article. For example, your floor-to-floor height as designed might be 118" (16 risers at 7 3/8"). You could change that to 17 risers at 6.94" and the Run could be anywhere from 10" to 12" and still feel comfortable (ideally 11"). Or if your design allows, you could have 18 risers at 6.56" with a Run of 12".

    Just be aware that some building codes specify a maximum number of risers from landing to landing, and that shorter risers results in more treads and greater tread depth, extending the overall run of the stairs.

  5. bpack88 | Jan 15, 2018 04:02pm | #5

    Is there a rule of thumb for taking stairs around a corner. To be able to fit mine in there would need to be three stairs on the corner.

  6. rovindelosreyes88 | Apr 01, 2018 08:40pm | #6

    The problem is when you have a small space in your ground floor like 40 square meters floor area placing your stair with that measurement (7" - 11") is really a challenge.

  7. Aric61 | Jan 04, 2020 04:37pm | #7

    Looking for a little more info give this blog a read...
    https://www.aricgitomerarchitect.com/7-eleven-not-just-convenience-comfort-well/

  8. user-535881 | Jan 24, 2020 08:41am | #8

    Isn't there a 3rd rule-of-thumb?
    Run x rise = (70 to 75)

    Any idea how to add it to the graphic representation? :)

  9. tauton_stupid_captch | Sep 18, 2020 07:39pm | #9

    I wonder if the graph should be a curve not a line? What about something like this?

    File format
  10. thosmiller | Apr 27, 2021 12:00pm | #10

    Is there a different approach for disabled access, such as individual who has hip arthritis and can do 5x19 much easier than steeper stairs?

    1. andyfrog | Dec 16, 2021 05:21pm | #11

      https://inspectapedia.com/Stairs/Stair_Design_for_Seniors.php I found this article about designing stairs for seniors. It seems like the takeaway is that with shorter step heights, you want longer tread depths to make climbing the stairs less awkward.

  11. user-7147782 | May 23, 2022 01:21pm | #12

    Excellent article, delighted you settled on 7 and 11, which is commercial spec and should be residential. Stair safety is a crucial consideration. Tread is not run, you subtract nosing overhang to get the run of the stair. Another article on stairs: https://www.proremodeler.com/beautiful-hazard

  12. user-119250 | May 14, 2024 09:44pm | #13

    The IRC (New Jersey Edition allow a minimum tread of 9" & maximum riser of 8 1/4" which is good if you're tight for space.

Log in or create an account to post a comment.

Sign up Log in

Become a member and get full access to FineHomebuilding.com

Framing

Framing

Trusted, in-depth guidance from the pros for framing a durable, code-compliant house

View Project Guide

View All Project Guides »

Become a member and get unlimited site access, including the Framing Project Guide.

Start Free Trial

Introduction to Framing
  • House Framing Concepts, Tips, and More
Framing Tools, Techniques, and Materials
  • Tools
  • Techniques
  • Framing Lumber
  • Steel
Framing Floors
  • Floor Framing
  • Engineered Floors
  • Floor Sheathing
Framing Walls
  • Wall Framing Basics
  • Layout
  • Wall Assembly
  • Raising and Straightening Walls
  • Framing Rough Openings
  • Blocking
Framing Stairs
  • Stair Layout
  • Building Stairs
Framing Roofs
  • Roof-Framing Basics
  • Roof Design
  • Laying Out and Cutting Rafters
  • Framing Valleys
  • Working with Trusses
  • Dormers
  • Special Situations
Efficient Framing Methods
  • Advanced Framing
  • Double-Stud Walls
Timber Framing
  • Timber-Frame Construction
  • Timber-Frame Design

Fine Home Building

Newsletter Sign-up

  • Fine Homebuilding

    Home building tips, offers, and expert advice in your inbox.

  • Green Building Advisor

    Building science and energy efficiency advice, plus special offers, in your inbox.

  • Old House Journal

    Repair, renovation, and restoration tips, plus special offers, in your inbox.

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters

Follow

  • Fine Homebuilding

    Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.

    Start Free Trial Now
    • Facebook
    • Instagram
    • X
    • LinkedIn
  • GBA Prime

    Get instant access to the latest developments in green building, research, and reports from the field.

    Start Free Trial Now
    • Facebook
    • YouTube
  • Old House Journal

    Learn how to restore, repair, update, and decorate your home.

    Subscribe Now
    • Facebook
    • Instagram
    • X
  • Fine Homebuilding

    Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.

    Start Free Trial Now
    • Facebook
    • Instagram
    • X
    • LinkedIn
  • GBA Prime

    Get instant access to the latest developments in green building, research, and reports from the field.

    Start Free Trial Now
    • Facebook
    • YouTube
  • Old House Journal

    Learn how to restore, repair, update, and decorate your home.

    Subscribe Now
    • Facebook
    • Instagram
    • X

Membership & Magazine

  • Online Archive
  • Start Free Trial
  • Magazine Subscription
  • Magazine Renewal
  • Gift a Subscription
  • Customer Support
  • Privacy Preferences
  • About
  • Contact
  • Advertise
  • Careers
  • Terms of Use
  • Site Map
  • Do not sell or share my information
  • Privacy Policy
  • Accessibility
  • California Privacy Rights

© 2025 Active Interest Media. All rights reserved.

Fine Homebuilding receives a commission for items purchased through links on this site, including Amazon Associates and other affiliate advertising programs.

  • Home Group
  • Antique Trader
  • Arts & Crafts Homes
  • Bank Note Reporter
  • Cabin Life
  • Cuisine at Home
  • Fine Gardening
  • Fine Woodworking
  • Green Building Advisor
  • Garden Gate
  • Horticulture
  • Keep Craft Alive
  • Log Home Living
  • Military Trader/Vehicles
  • Numismatic News
  • Numismaster
  • Old Cars Weekly
  • Old House Journal
  • Period Homes
  • Popular Woodworking
  • Script
  • ShopNotes
  • Sports Collectors Digest
  • Threads
  • Timber Home Living
  • Traditional Building
  • Woodsmith
  • World Coin News
  • Writer's Digest
Active Interest Media logo
X
X
This is a dialog window which overlays the main content of the page. The modal window is a 'site map' of the most critical areas of the site. Pressing the Escape (ESC) button will close the modal and bring you back to where you were on the page.

Main Menu

  • How-To
  • Design
  • Tools & Materials
  • Video
  • Blogs
  • Forum
  • Project Guides
  • Reader Projects
  • Magazine
  • Members
  • FHB House

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Podcasts

  • FHB Podcast
  • ProTalk

Webinars

  • Upcoming and On-Demand

Popular Topics

  • Kitchens
  • Business
  • Bedrooms
  • Roofs
  • Architecture and Design
  • Green Building
  • Decks
  • Framing
  • Safety
  • Remodeling
  • Bathrooms
  • Windows
  • Tilework
  • Ceilings
  • HVAC

Magazine

  • Current Issue
  • Past Issues
  • Magazine Index
  • Subscribe
  • Online Archive
  • Author Guidelines

All Access

  • Member Home
  • Start Free Trial
  • Gift Membership

Online Learning

  • Courses
  • Project Guides
  • Reader Projects
  • Podcast

More

  • FHB Ambassadors
  • FHB House
  • Customer Support

Account

  • Log In
  • Join

Newsletter

Get home building tips, offers, and expert advice in your inbox

Signing you up...

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
See all newsletters
See all newsletters

Follow

  • X
  • YouTube
  • instagram
  • facebook
  • pinterest
  • Tiktok

Join All Access

Become a member and get instant access to thousands of videos, how-tos, tool reviews, and design features.

Start Your Free Trial

Subscribe

FHB Magazine

Start your subscription today and save up to 81%

Subscribe

This is your last free article.

Don't miss another expert tip or technique from building pros. Start your free trial today.

Start your FREE trial

Already a member? Log in

We hope you’ve enjoyed your free articles. To keep reading, become a member today.

Get complete site access to expert advice, how-to videos, Code Check, and more, plus the print magazine.

Start your FREE trial

Already a member? Log in

Privacy Policy Update

We use cookies, pixels, script and other tracking technologies to analyze and improve our service, to improve and personalize content, and for advertising to you. We also share information about your use of our site with third-party social media, advertising and analytics partners. You can view our Privacy Policy here and our Terms of Use here.

Cookies

Analytics

These cookies help us track site metrics to improve our sites and provide a better user experience.

Advertising/Social Media

These cookies are used to serve advertisements aligned with your interests.

Essential

These cookies are required to provide basic functions like page navigation and access to secure areas of the website.

Delete My Data

Delete all cookies and associated data