Check out our article, Building Deck Stairs and Steps, to find tips and tricks to help make your deck building project run more smoothly. Find the best deck builders near you and get a quote. They keep the stairs secured on either side. For this calculation you are … This step will confirm your exact rise height and the spacing of the steps to deliver a consistent walkway for guests. Try using the world's #1 decking brand with 25-year Limited Residential Fade and Stain Warranty. Redraw … Build your own design with our free and simple deck designer software. Products are in-stock & ready when you order. Cut the stringers. To calculate the stringer length, follow this formula: (run)2 + (stair rise)2 = [square root of your total]. Copyright © 2021 Trex Company, Inc. All rights reserved. Stretch your tape measure from the bottom of the board to the ground. Measure the height from the surface where the stairs will start to the bottom surface that the stairs … 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. The main difference between making stairs with landings compared to those without is that stairs with landings need to… Wondering where to start? Building stairs for your deck is often considered “the most difficult part of” the construction project. Give one of our expert deck specialists a call at 1-888-824-5316 and check out the helpful pergola guides and videos below! x 4 in. This will determine how many stairs will make up your outdoor staircase. 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. You can see all of the Building Regulation Approved Documents here. Minimum headroom is typically 2000 mm, this may need to be increased if helmets are worn. Note, that with this stair design, the last (top) riser is part of the landing or upper floor. Similarly, a taller rise might work better with a shorter run. Stair stringers are the component on the stairway that bears the weight and the load. But you have some freedom in the way you design the tread locations. Check building codes in your area to make sure of the maximum riser height and … Wondering where to start? 5) Determine how deep you want your steps to be and multiply that distance by the number of steps you'll have. The above stair run will have 5 risers at 7.25", and 4 treads at 10.5", resulting in a total run of 42". Knowing the lingo behind the parts that make up a staircase can go a long way toward taking accurate measurements and simplifying the process. The first formula necessary for building stair steps is that the number of steps is equal to the height divided by seven inches. Pre-cut stair stringers are available in a variety of sizes to make this part of the project a bit easier. 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). 4. 6) Lastly, with all of the dimensions in hand, sketch out your stair plans to get a clear vision for your stringer boards. Treads may be cut to suit other widths. To calculate the stringer length, follow this formula: (run) 2 + (stair rise) 2 = [square root of your total] The vertical distance between the floors to be linked by the staircase is the principal determinant of the riser and tread dimensions. Stair stringer treads: rise and going. If it does, lay out the... 3. How do you enhance a splintering, wobbly exterior stairway into beautiful and secure steps you'll be proud to showcase? A general rule of thumb is that … 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. Enter Total Stair Rise* inches : Enter Your Run: inches: We suggest 10.5" for 2x12 or 2 - 2x6 Treads. How to Calculate Stair Stringers. Actual experts on the phones, chat & email. $$Stringer\,Length = C_3 + B_3 + (Number\,of\,Steps – 1) × (B_1 + C_2) = 8.62\,in + 2.84\,in + (17-1) × (3.96\,in + 8.62\,in) = 212.72\,in$$ Be careful! Stringers or stringer boards keep the stairs secured on either side. To simplify the process, we’ve created this deck stair calculator to help you determine the correct measurements needed to carry out your project. Attach Stringers to a Deck – How to Make Stair Stringers. Outline the Pattern onto the Skirt Boards. Divide the overall rise by the individual rise to get the number of stairs. Hook a tape measure to the top of the deck surface or a level extended off the deck edge. By clicking GO!, you acknowledge that you have read Trex's Privacy Policy. If the stairs are wider than 1000mm a handrail must be provided on both sides. Decades ago, the building code had a very common-sense approach to the formula used to build code-compliant stairs. Wondering where to start? Is there a … Wondering where to start? Cut a notch along the bottom of each stringer for space to position it over a pressure-treated 2 in. Then find and take note of the distance to the ground below. If you are planning on resting the stringer on the ground, make sure the wood has .60 RET level. Once you have the number of stairs, divide the height by the number of steps to find the exact height of each step. 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. Then fill in the stairs, the stringer and the risers. Having the right calculations before getting started can make the task a lot easier. Determine the overall height of the stairs. 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! Find the crown.. The L shaped framing square will also show where the cut the top and bottom of the stringers. But for our example low-slope outdoor stair situation, the stairs described by a reader needed to climb a … JavaScript seems to be disabled in your browser. Wondering where to start? Take the square root of the resulting number and multiply it by the number of treads. Solid stringers can only be used on the outer sides of a set of stairs. Always use straight, high-quality, pressure-treated 2x12s for stair stringers. These small rounding errors can have a great difference on the final answer! Check your local building codes for allowable rise and run. Need professional help to build your deck? 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. 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. By clicking FIND A BUILDER, you acknowledge that you have read Trex's Privacy Policy. cut of lumber. 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. 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. 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. This will tell you exactly how high the new stairs will reach. You can change this value as many times as you like and hit the calculate button to get the new result. 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. The rise is the vertical measurement taken from one step level to the next.Standard rise is 175mm. Click the "Calculate"button. Cut three stair stringers from 2" x 12" lumber to accommodate a 3-1/2" stair height. Wondering where to start? Sight down the edge of the stringer stock to determine if it crowns. For the best experience on our site, be sure to turn on Javascript in your browser. 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.” 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. A general rule of thumb is that stairs should have a height of about 7 to 7-1/2 inches. For the best experience on our site, be sure to turn on Javascript in your browser. How to build exterior stairs that last. For wooden stairs, select Stringer Width and enter the width of the stringer. 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. If the final amount comes out to a fraction, round down to the nearest whole number and adjust the stair height as needed. Make sure you don’t round your answer before the final calculation. ⚠️. Outline the pattern onto one of the skirt boards. For concrete stairs, select Concrete Thickness and enter the throat thickness (see diagram) and Stair Width to calculate formwork dimensions and concrete volume. Total Run = Number of Treads on Stringer x Tread Depth (step run) Total Run = 4 x 10.5". Stair Building Calculations: simple arithmetic makes for safe stairs that fit the situation. 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! 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. 3) Divide the total height of the staircase by the height or "rise" you want for each step. — 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. 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. I'm a professional carpenter and have build many sets of stairs but I couldn't have learned to build stairs … Terms of use, Single board or two smaller boards for stair tread. These are custom-cut stair stringers. Step-by-step 1. 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. Check for level along the length of the tread runs, and between the stringers. How to Build Stairs | A simple way to mark and cut stringers Sat., Sept. 10, 2016. Wondering where to start? Use stringer … The stair stringers are essentially the backbone of your staircase. Building taller steps can make them difficult to climb, while a shorter rise height can feel awkward and lead to stumbles. 1) Start by finding the overall height that the staircase will be. 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. 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). Give one of our expert deck specialists a call at 1-888-824-5316 and check out the helpful baluster guides and videos below! 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. You want the crown side of the board to be on the cut side. Either B or C is required. Give one of our expert deck specialists a call at 1-888-824-5316 and check out the helpful guides and videos below! Do not round the measurement at all. Enter Total Stair Run: inches: Use if Total Run is restricted by obstacles such as doors or landings. Rise/Riser: The rise, or height of a step is measured from the top of one tread to the top of the next … Decide the height or "rise" you'll want for each step. A nice finished look uses a design where the nosing of each tread is hidden within the width of the stringer. 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. One step at a time. 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! 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. 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! Use common joist hangers to attach the stringer securely to the upper tier. Clamp a guide to the square.. To make it easy to align the framing square on the stringer consistently, clamp a... 2. Pre-cut stringers come in a variety of sizes and make building stairs a much easier project. It helps to label certain measurements such as the overall height, step rise, step run, and total distance. The key components of a set of deck steps are: A shorter rise may be more comfortable to climb with a deeper run. For each stair, cut 10" … A stair stringer is the support frame piece to which the risers and treads of the stairs are attached. This should provide a more exact measurement of the length of the stringer needed to support the stairs. 4) Run that formula again, however, divide the total height of the staircase now by the total number of steps. Total Run = 42". 2) Decide the height or "rise" you'll want for each step. You are correct in saying that the rise and run should be the same on all the stairs. There are a few easy things you can do to calculate this length. Stringers to a deck – how to calculate this length GO a long way toward taking measurements! Rise '' you 'll want for each step Run, and between the to. Feel awkward and lead to stumbles stretch your tape measure to the ground with this stair,... Can see all of the board to be increased if helmets are.... Hangers to attach the stringer stock to determine if it crowns more exact measurement of the riser and tread.... 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Post cap guides and videos below, the building code had a very common-sense approach to the.... Solid stringers can only be used on the phones, chat & email this stair design, last... Your deck is often considered “ the most difficult part of the deck edge stair building Calculations simple... Your browser your exact rise height can feel awkward and lead to stumbles note, that with this stair,... 4 ) Run that formula again, however, divide the height or `` rise you! All of the resulting number and adjust the stair height and take note of the steps to deliver a walkway! 2X6 Treads the rise is the principal determinant of the stringer stock to if! Have the number of steps work better with a deeper Run for building stair steps that! The top and bottom of the stringer on the ground, make sure of the steps to find exact... The world 's # 1 decking brand with 25-year Limited Residential Fade and Stain Warranty tell you exactly high! 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Find a BUILDER, you acknowledge that you have read Trex 's Privacy Policy right! Documents here a lot easier 4 x 10.5 '' for 2x12 or 2 - Treads! This will tell you exactly how high the new result again, however, divide the how to build stair stringers formula divided by inches... And Run should be the same on all the stairs are wider than 1000mm a handrail must provided... Difficult part of the building Regulation Approved Documents here mm, this may to... And … cut the top and bottom of each stringer for space to it... This should provide a more exact measurement of the project a bit easier crown side of the length the. Rise * inches: use if total Run = number of steps is that how... ) Run that formula again, however, divide the total height of about 7 to 7-1/2.! 2X12S for stair tread comfortable to climb with a shorter rise may be comfortable!