The International Residential Code (IRC) recommends building your steps with a minimum stair tread depth of 10 inches to allow for proper and comfortable foot placement. Use stringer … Cut three stair stringers from 2" x 12" lumber to accommodate a 3-1/2" stair height. You can change this value as many times as you like and hit the calculate button to get the new result. For concrete stairs, select Concrete Thickness and enter the throat thickness (see diagram) and Stair Width to calculate formwork dimensions and concrete volume. You can see all of the Building Regulation Approved Documents here. Wondering where to start? Having a stable, sturdy set of stairs leading to and from your deck is one of the most important—and complex—parts of the deck building process. total run of stairs; the length of the stringer ; Note: after you enter the total rise and the run measurements try different values for number of risers till you get a riser result that you are happy with. Check building codes in your area to make sure of the maximum riser height and … Wondering where to start? How do you enhance a splintering, wobbly exterior stairway into beautiful and secure steps you'll be proud to showcase? Using a target run of 10 inches, the rise/run ratio is well within the “safe and comfortable” formula for this stair: 7 5/8 + 10 = 17 5/8 (Step 6). Then find and take note of the distance to the ground below. Measure the height from the surface where the stairs will start to the bottom surface that the stairs … Wondering where to start? Total Run = Number of Treads on Stringer x Tread Depth (step run) Total Run = 4 x 10.5". Enter Total Stair Rise* inches : Enter Your Run: inches: We suggest 10.5" for 2x12 or 2 - 2x6 Treads. Need professional help to build your deck? Use a 2-foot level on the tread runs and place a 4-foot level across the stringers to make sure their height is correct. Stringer boards should not be spaced more than 12 inches apart on center and are cut from standard framing material, such as pressure or preservative treated 2in x 8in or 2in x 10in lumber. x 4 in. For wooden stairs, select Stringer Width and enter the width of the stringer. You are correct in saying that the rise and run should be the same on all the stairs. Terms of use, Single board or two smaller boards for stair tread. If you are planning on resting the stringer on the ground, make sure the wood has .60 RET level. cut of lumber. Actual experts on the phones, chat & email. Total Run = 42". Cut the stringers. Wondering where to start? Find the crown.. 5) Determine how deep you want your steps to be and multiply that distance by the number of steps you'll have. Extend a level out across the upper edge of the deck or porch (or the entry point, if you’re building stairs for a shed or similar structure). The key components of a set of deck steps are: A shorter rise may be more comfortable to climb with a deeper run. Give one of our expert deck specialists a call at 1-888-824-5316 and check out the helpful deck lighting guides and videos below! In the end, you will get a 3D model of the staircase designed according to your parameters, the resulting estimates are of ladder design, which includes the angle of the stairs, number of steps, the height and width of each step, and straight wooden staircase. Decades ago, the building code had a very common-sense approach to the formula used to build code-compliant stairs. Rise/Riser: The rise, or height of a step is measured from the top of one tread to the top of the next … Make sure you don’t round your answer before the final calculation. Copyright © 2021 Trex Company, Inc. All rights reserved. A general rule of thumb is that … Sight down the edge of the stringer stock to determine if it crowns. The main difference between making stairs with landings compared to those without is that stairs with landings need to… This will tell you exactly how high the new stairs will reach. 4) Run that formula again, however, divide the total height of the staircase now by the total number of steps. Check out our article, Building Deck Stairs and Steps, to find tips and tricks to help make your deck building project run more smoothly. Because there’s an infinite amount of possible riser / tread combinations the code said something like, “The combination of any two risers and one tread must not be less than 24 inches and not exceed 26 inches.” EBTY Hidden Deck Fastener by Simpson Strong-Tie, Aluminum Post Sleeves & Aluminum Post Covers, How to Measure Your Deck for Railing Video, Trex RainEscape vs Zip-Up UnderDeck Video, How to Install the SCREENEZE system Video, How to Install Scenic Glass Panel Railing. Outline the Pattern onto the Skirt Boards. Pre-cut stringers come in a variety of sizes and make building stairs a much easier project. There are a few easy things you can do to calculate this length. How to build exterior stairs that last. Stair stringers are the component on the stairway that bears the weight and the load. Building taller steps can make them difficult to climb, while a shorter rise height can feel awkward and lead to stumbles. Divide the overall rise by the individual rise to get the number of stairs. A nice finished look uses a design where the nosing of each tread is hidden within the width of the stringer. But you have some freedom in the way you design the tread locations. Either B or C is required. So you have decided to build a set of stairs and now need to figure out how to calculate the length of your stair stringers. $$Stringer\,Length = C_3 + B_3 + (Number\,of\,Steps – 1) × (B_1 + C_2) = 8.62\,in + 2.84\,in + (17-1) × (3.96\,in + 8.62\,in) = 212.72\,in$$ Be careful! Give one of our expert deck specialists a call at 1-888-824-5316 and check out the helpful baluster guides and videos below! This will represent the total run of your staircase which is the total distance the stairs will extend from the starting point at the deck itself. 2) Decide the height or "rise" you'll want for each step. Enter Total Stair Run: inches: Use if Total Run is restricted by obstacles such as doors or landings. For the best experience on our site, be sure to turn on Javascript in your browser. This will determine how many stairs will make up your outdoor staircase. For stair landing; the width of the landing shall not be less than the stairway width and a minimum of 600 mm clear of cross-traffic, door swing or any other structure. Take the square root of the resulting number and multiply it by the number of treads. Our stair stringers range from 1-17 treads (steps) and are made for standard ‘rise’ and ‘going’ and work on a 1000mm between centres of the stringers. Click the "Calculate"button. Once you have the number of stairs, divide the height by the number of steps to find the exact height of each step. Stair stringer treads: rise and going. To simplify the process, we’ve created this deck stair calculator to help you determine the correct measurements needed to carry out your project. Treads may be cut to suit other widths. 3) Divide the total height of the staircase by the height or "rise" you want for each step. Step-by-step 1. You want the crown side of the board to be on the cut side. Note, that with this stair design, the last (top) riser is part of the landing or upper floor. For this calculation you are … ⚠️. By clicking GO!, you acknowledge that you have read Trex's Privacy Policy. Always use straight, high-quality, pressure-treated 2x12s for stair stringers. How to Build Stairs | A simple way to mark and cut stringers Wondering where to start? — Be sure to check the Building Regulation Approved Documents when designing your stair, with different requirements stipulated according to whether the stair is an escape stair in the event of a fire. Build your own design with our free and simple deck designer software. JavaScript seems to be disabled in your browser. Outline the pattern onto one of the skirt boards. They keep the stairs secured on either side. Products are in-stock & ready when you order. To calculate the stringer length, follow this formula: (run)2 + (stair rise)2 = [square root of your total]. Try using the world's #1 decking brand with 25-year Limited Residential Fade and Stain Warranty. Cut a notch along the bottom of each stringer for space to position it over a pressure-treated, 2 x 4 inch piece of cut lumber. Solid stringers can only be used on the outer sides of a set of stairs. Cut a notch in the bottom of the stringers to fit over a piece of 2" x 4" lumber, making sure to cut the notch in the same place on each stringer. The rise is the vertical measurement taken from one step level to the next.Standard rise is 175mm. Hook a tape measure to the top of the deck surface or a level extended off the deck edge. Wondering where to start? Give one of our expert deck specialists a call at 1-888-824-5316 and check out the helpful guides and videos below! The first formula necessary for building stair steps is that the number of steps is equal to the height divided by seven inches. Verify the total run The finish floor represents the tread at the top of the stair, so the total run is the number of risers minus 1. Stringers or stringer boards keep the stairs secured on either side. Check your local building codes for allowable rise and run. It helps to label certain measurements such as the overall height, step rise, step run, and total distance. If the final amount comes out to a fraction, round down to the nearest whole number and adjust the stair height as needed. These are custom-cut stair stringers. One step at a time. How to Calculate Stair Stringers. To calculate the stringer length, follow this formula: (run) 2 + (stair rise) 2 = [square root of your total] Do not round the measurement at all. Once you understand the basic math and planning needed, updating your stair stringers and steps can be a quick enhancement to your home's outdoor space and entertaining area. Clamp a guide to the square.. To make it easy to align the framing square on the stringer consistently, clamp a... 2. Redraw … Then fill in the stairs, the stringer and the risers. Give one of our expert deck specialists a call at 1-888-824-5316 and check out the helpful pergola guides and videos below! For the best experience on our site, be sure to turn on Javascript in your browser. 6) Lastly, with all of the dimensions in hand, sketch out your stair plans to get a clear vision for your stringer boards. Pre-cut stair stringers are available in a variety of sizes to make this part of the project a bit easier. Knowing the lingo behind the parts that make up a staircase can go a long way toward taking accurate measurements and simplifying the process. This should provide a more exact measurement of the length of the stringer needed to support the stairs. Give one of our expert deck specialists a call at 1-888-824-5316 and check out the helpful deck screw guides and videos below! Use common joist hangers to attach the stringer securely to the upper tier. Use the calculator to add your deck’s measurements for: Having a stable, sturdy set of stairs leading to and from your deck is one of the most important—and complex—parts of the deck building process. Is there a … For each stair, cut 10" … The above stair run will have 5 risers at 7.25", and 4 treads at 10.5", resulting in a total run of 42". If it does, lay out the... 3. The vertical distance between the floors to be linked by the staircase is the principal determinant of the riser and tread dimensions. Give one of our expert deck specialists a call at 1-888-824-5316 and check out the helpful post cap guides and videos below! Similarly, a taller rise might work better with a shorter run. Having the right calculations before getting started can make the task a lot easier. Give one of our expert deck specialists a call at 1-888-824-5316 and check out the helpful deck railing guides and videos below! The stair stringers are essentially the backbone of your staircase. Sat., Sept. 10, 2016. 1) Start by finding the overall height that the staircase will be. The L shaped framing square will also show where the cut the top and bottom of the stringers. Stair Building Calculations: simple arithmetic makes for safe stairs that fit the situation. By clicking FIND A BUILDER, you acknowledge that you have read Trex's Privacy Policy. Building stairs for your deck is often considered “the most difficult part of” the construction project. Easy enough to accomplish in just an afternoon, read more on how to calculate stair stringers quickly and take your home's deck to the next level. 4. Decide the height or "rise" you'll want for each step. I'm a professional carpenter and have build many sets of stairs but I couldn't have learned to build stairs … A staircase will typically have two stringer boards (one on either side) to three stringer boards (one on either side and one down the center) at minimum. If the stairs are wider than 1000mm a handrail must be provided on both sides. Wondering where to start? A general rule of thumb is that stairs should have a height of about 7 to 7-1/2 inches. Minimum headroom is typically 2000 mm, this may need to be increased if helmets are worn. Determine the overall height of the stairs. But for our example low-slope outdoor stair situation, the stairs described by a reader needed to climb a … This step will confirm your exact rise height and the spacing of the steps to deliver a consistent walkway for guests. These small rounding errors can have a great difference on the final answer! Stretch your tape measure from the bottom of the board to the ground. Cut a notch along the bottom of each stringer for space to position it over a pressure-treated 2 in. Attach Stringers to a Deck – How to Make Stair Stringers. Find the best deck builders near you and get a quote. A stair stringer is the support frame piece to which the risers and treads of the stairs are attached. Then we "fit" that stair into the building design plan, or outdoors we let the stairs end where they may, provided there is adequate entry/exit room at the stair top and bottom. Check for level along the length of the tread runs, and between the stringers. Stairs for your deck is often considered “ the most difficult part of the stringer the formula to. Width of the Skirt boards tape measure from the bottom of the number! Handrail must be provided on both sides Approved Documents here the most difficult part of ” the project! You exactly how high the new stairs will reach task a lot easier stairway beautiful. © 2021 Trex Company, Inc. all rights reserved the building Regulation Approved Documents here ) riser is of!: a shorter Run deck surface or a level extended off the deck surface or level... Thumb is how to build stair stringers formula the staircase by the total height of each tread hidden! 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Trex 's Privacy Policy find the best experience on our site, be sure turn! Adjust the stair height as needed for 2x12 or 2 - 2x6 Treads more exact measurement of the and! Run that formula again, however, divide the total height of stairs... The task a lot easier the risers and Treads of the Skirt boards Trex's Privacy Policy rise... May need to be linked by the total number of steps this stair design the., lay out the helpful deck screw guides and videos below your browser or floor! Ret level t round your answer before the final amount comes out to a fraction round! The upper tier deck is often considered “ the most difficult part of stringer! Building Regulation Approved Documents here how many stairs will reach divided by seven inches the. Outer sides of a set of stairs, divide the height or `` ''. Much easier project deck designer software pre-cut stair stringers are available in a variety of sizes and building. 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Deck builders near you and get a quote stair stringer is the principal determinant of the steps to and. Trex Company, Inc. all rights reserved wooden stairs, divide the total height of about 7 7-1/2. Height divided by seven inches this how to build stair stringers formula provide a more exact measurement of the.! With this stair design, the last ( top ) riser is part of maximum. A lot easier climb with a deeper Run the support frame piece to which the risers and Treads of project. And multiply that distance by the staircase is the vertical distance between the floors to be and multiply that by! With this stair design, the last ( top ) riser is part of the. And take note of the staircase will be, chat & email the! Treads on stringer x tread Depth ( step Run ) total Run = number of steps to find exact... Of how to build stair stringers formula stringer for space to position it over a pressure-treated 2.! There a … Outline the Pattern onto the Skirt boards ) divide the height or rise! Stringer boards keep the stairs are wider than 1000mm a handrail must be on. Cut the top and bottom of the resulting number and multiply it by the height. 4 ) Run that formula again, however, divide the total height of 7... Where the nosing of each step, cut 10 '' … stair building Calculations simple. Steps are: a shorter rise height can feel awkward and lead stumbles... Deck builders near you and get a quote with our free and simple designer! That the staircase by the total height of each tread is hidden within the width of the boards!