[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"doc-seo-663961-105":3,"detail-sidebar-cat-0-en-105":79,"doc-detail-663961-en":129},{"code":4,"msg":5,"data":6},0,"ok",{"site_id":7,"language":8,"slug":9,"title":10,"keywords":11,"description":12,"schema_data":13,"social_meta":72,"head_meta":74,"extra_data":76,"updated_unix":78},105,"en","pdhonline-course-c662-stairs-stairways","PDHonline Course C662 - Stairs & Stairways","","PDHonline Course C662 introduces stair design from historical origins to practical planning and safety considerations. It explains how builders evolved stair and stairway construction, emphasizing step uniformity and “mental cadence” for balance and accident prevention. The course then reviews legacy stair code formulas, including tread-riser constraints, and contrasts them with modern code requirements, beginning with Section 1009 limits for riser heights.",{"@graph":14,"@context":71},[15,34,54],{"@type":16,"itemListElement":17},"BreadcrumbList",[18,23,27,31],{"item":19,"name":20,"@type":21,"position":22},"https://docshare.wps.com","Home","ListItem",1,{"item":24,"name":25,"@type":21,"position":26},"https://docshare.wps.com/document/","Document",2,{"item":28,"name":29,"@type":21,"position":30},"https://docshare.wps.com/document/exam/","Exam",3,{"item":32,"name":10,"@type":21,"position":33},"https://docshare.wps.com/document/pdhonline-course-c662-stairs-stairways/663961/",4,{"url":32,"name":10,"@type":35,"image":36,"author":41,"headline":10,"publisher":44,"fileFormat":47,"inLanguage":8,"description":12,"dateModified":48,"datePublished":48,"encodingFormat":47,"isAccessibleForFree":49,"interactionStatistic":50},"DigitalDocument",{"url":37,"@type":38,"width":39,"height":40},"https://docshare.wps.com/thumbnails/pdhonline-course-c662-stairs-stairways/663961.png","ImageObject",300,407,{"name":42,"@type":43},"jayni","Person",{"url":19,"name":45,"@type":46},"DocShare","Organization","application/pdf","2026-10-29",true,{"@type":51,"interactionType":52,"userInteractionCount":22},"InteractionCounter",{"@type":53},"ViewAction",{"@type":55,"mainEntity":56},"FAQPage",[57,63,67],{"name":58,"@type":59,"acceptedAnswer":60},"Why did ancient civilizations carve steps in mountainous areas?","Question",{"text":61,"@type":62},"They needed a way to ascend and descend rough terrain, so steps were carved into mountain rocks to facilitate escalation.","Answer",{"name":64,"@type":59,"acceptedAnswer":65},"What issue can arise when stair step dimensions are not uniform?",{"text":66,"@type":62},"Breaking uniformity disrupts the involuntary cadence people expect on stairs, which can lead to missteps, unwanted accidents, and unsafe conditions.",{"name":68,"@type":59,"acceptedAnswer":69},"What key change do new building codes make compared with old formulas?",{"text":70,"@type":62},"Modern codes abandon the earlier tread-riser formulas and instead specify direct limits in Section 1009, starting with maximum and minimum stair riser heights.","https://schema.org",{"og:url":32,"og:type":73,"og:title":10,"og:site_name":45,"og:description":12},"article",{"robots":75,"canonical":32},"index,follow",{"doc_id":77,"site_id":7},663961,1793235471,{"code":4,"msg":80,"data":81},"success",[82,86,90,93,98,103,108,113,118,121,125],{"id":22,"doc_module":4,"doc_module_name":25,"category_name":83,"show_sort_weight":84,"slug":85},"Story & Novel",90,"story-novel",{"id":26,"doc_module":4,"doc_module_name":25,"category_name":87,"show_sort_weight":88,"slug":89},"Literature",80,"literature",{"id":33,"doc_module":4,"doc_module_name":25,"category_name":29,"show_sort_weight":91,"slug":92},70,"exam",{"id":94,"doc_module":4,"doc_module_name":25,"category_name":95,"show_sort_weight":96,"slug":97},5,"Comic",60,"comic",{"id":99,"doc_module":4,"doc_module_name":25,"category_name":100,"show_sort_weight":101,"slug":102},6,"Technology",50,"technology",{"id":104,"doc_module":4,"doc_module_name":25,"category_name":105,"show_sort_weight":106,"slug":107},7,"Healthcare",40,"healthcare",{"id":109,"doc_module":4,"doc_module_name":25,"category_name":110,"show_sort_weight":111,"slug":112},8,"Research & Report",30,"research-report",{"id":114,"doc_module":4,"doc_module_name":25,"category_name":115,"show_sort_weight":116,"slug":117},9,"Religion & Spirituality",20,"religion-spirituality",{"id":116,"doc_module":4,"doc_module_name":25,"category_name":119,"show_sort_weight":116,"slug":120},"World Cup","world-cup",{"id":122,"doc_module":4,"doc_module_name":25,"category_name":123,"show_sort_weight":122,"slug":124},10,"Lifestyle","lifestyle",{"id":126,"doc_module":4,"doc_module_name":25,"category_name":127,"show_sort_weight":94,"slug":128},19,"General","general",{"code":4,"msg":80,"data":130},{"doc_id":77,"user_id":131,"nickname":42,"user_avatar":132,"doc_module":4,"category_id":33,"category_name":29,"doc_title":10,"doc_description":12,"doc_content":133,"file_id":134,"file_url":135,"file_type":136,"file_size":137,"view_count":22,"is_deleted":4,"is_public":22,"is_downloadable":22,"audit_status":22,"page_count":101,"language":138,"language_code":8,"site_id":7,"html_lang":8,"table_of_contents":139,"faqs":140,"seo_title":141,"seo_description":12,"update_tm":78,"read_time":142},3985747859343,"https://ap-avatar.wpscdn.com/davatar_276721f389ce27ea32af1340a28f341c","|  |\n| --- |\n| |\n| PDHonline Course C662 (4 PDH)\u003Cbr>Stairs & Stairways\u003Cbr>Instructor: Ruben A. Gomez, PE\u003Cbr>2026\u003Cbr>PDH Online • PDH Central\u003Cbr>9820 Bucklow Hill Dr Orlando, FL 32832-7126\u003Cbr>[info@PDHonline.com](info@PDHonline.com)\u003Cbr>[PDHonline.com](PDHonline.com)[ ](PDHonline.com)[PDHonline.org](PDHonline.org)\u003Cbr>An Approved Continuing Education Provider |\n\n1.0 PROLOGUE  \nThe old civilizations with enclaves in the mountainous areas of Europe, Asia, South and North America, such as the tribes of Catal Huyuk in today’s Turkey or the Incas of Machu Pichu in Los Andes, found the need to carve steps in the mountain rocks to facilitate escalation through the rough terrain.  \nIn building construction, stairs became a necessity the moment civilized man decided to elevate the house floor above the surrounding ground as in the Sumerian Ziggurats orthe Harapan cities of the Indus Valley. He first started with a single stepping stone and kept on adding up as the need arose, and little by little we ended up with the stairs and stairways we have all around us today.  \nStairs come in all kinds, shapes, configurations and materials. In this course we will cover all the basic information that is needed to know about stairs and be successful in planning an efficient, comfortable and reasonably safe set of stairs.  \nWhen you plan your building layout and start calculating your floor to floor heights by adding the required finished floor to ceiling space, as well as the interstitial space plus the structural thickness allowances so to arrive to the “magical figure”. While in that process you need to keep in mind the stairway(s) configuration and details, for you do not want to end up with risers with fractional dimensions ending in 1/16ths or 1/32nds of an inch. Your draftsmen, builders, stair fabricators and carpenters coming after you will be appreciative of your anticipation.  \nIn the “old times” a 7” x 10” combination of riser and tread was considered ideal, but as time passed and experience accumulated, the practitioners figured that in order to accommodate the shoe size found in 95% of the human adult population, an 11” tread was a more convenient dimension, therefore, in these “new modern times” you will hear that the most comfortable riser/tread combination should be as close as possible to 7” x 11”, which the reader will find often as being used in the pages of this course.  \nAnother important factor which should be kept in mind is the workings of the human mind. As a person ascends or descends (particularly the latter) a stairway, he (or she) develops an involuntary cadence where there is a mindset based on an unconscious expectation of uniformity when it comes to the size of the steps. Such a cadence is particularly important to help maintain the person’s balance, efficiency and a feeling of safety. Therefore, any break in the uniformity that sponsors disruption of said cadence may provoke missteps, unwanted accidents and therefore, should be avoided at all cost.  \nThat is why when a forensic engineer is first confronted with a stair accident, he will pull his tape measure and look for inconsistencies in riser dimensions and unevenness, before he continues on the pursuit of other factors such as: stair width, configuration, tread depth, friction factors, condition of the surface, code compliance and so on.  \n2.0 OLD CODES’ FORMULAE  \nOld building codes were very eager to furnish “fit all sizes” formulas that worked well for as long as the riser/tread configuration was kept within the proximity of the 7 x 10 proportion. However, when either the riser or the tread were taken to the outer edges of those limits, the resulting stairs were borderline cases of absurdity and were close to impossible to maintain in compliance with the principle of continuity and “mental cadence” mentioned in the prologue above.  \nBelow are the most known and used of those rules and formulas. Please bear in mind that any of the tread dimensions resulting from ","cbCaispkfK9n4Cbm","https://ap.wps.com/l/cbCaispkfK9n4Cbm","pdf",1962112,"English","# Prologue\n# Old Codes’ Formulae\n# New Codes’ Approach","[{\"question\":\"Why did ancient civilizations carve steps in mountainous areas?\",\"answer\":\"They needed a way to ascend and descend rough terrain, so steps were carved into mountain rocks to facilitate escalation.\"},{\"question\":\"What issue can arise when stair step dimensions are not uniform?\",\"answer\":\"Breaking uniformity disrupts the involuntary cadence people expect on stairs, which can lead to missteps, unwanted accidents, and unsafe conditions.\"},{\"question\":\"What key change do new building codes make compared with old formulas?\",\"answer\":\"Modern codes abandon the earlier tread-riser formulas and instead specify direct limits in Section 1009, starting with maximum and minimum stair riser heights.\"}]","PDHonline Course C662 - Stairs & Stairways | PDF",126]