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This document provides building code specifications, sketches, photographs, and examples of defects used in inspecting indoor or outdoor stairs, railings, landings, treads, and related conditions for safety and proper construction.

A stair inspection checklist provided in this document outlines information to collect during a field investigation of the condition of an interior or exterior stairway for safety defects. Having investigated cases of severe injury related to falls and railing collapses we developed this field data collection checklist. We also include references to key documents on building codes and stair and railing safety. © Copyright 2009 Daniel Friedman, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use links at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

Catalog of Common Stair & Railing Specifications, Stair & Rail Defects & Trip Hazards

Stairway, Railing, Landing Basic Dimensions & Rules

• Attic stairs are often non-standard, steep, missing railings; attic folding stairs or pull-down stairs have special requirements for securing, fitting, etc.
• Balusters & Railing Enclosures (vertical posts comprising the barrier in guards and railings)
• Basement stairs and basement walkout stair covers
• Checklist & Form for stair inspections is provided here
• Codes: building codes for stair construction are similar but not identical, as we compare in some notes
• Exterior stairs may present additional non-standard tripping hazards
• Fire stopping is required on interior stairs in some constructions
• Guards (railings on landings and open hallways, porches, screened porches, balconies that are more than 30" above floors or grade)
• Lighting: shall be provided over stairs, with switches at top and bottom
• Railings: required on any run of any continuous run of steps comprising 4 or more risers
• Stairway headroom, height, width width and stair dimension specifications
• Stairway landings are required depending on stair total height or in other conditions
• Step riser specifications for height, angle, etc.
• Step stringer defects such as rot, loose connections, bending, loss of tread connection
• Step tread specifications for width, depth, uniformity, & examples of defects
• Stair tread nose requirement on some treads, shape and angle requirements

Separate specifications are provided for circular stairs and winder stairs

Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

STAIRS, RAILINGS, LANDING INSPECTIONS, CODES
  Attic stairs
  Balusters & Railing Enclosures
  Basement Stairs & Walkout Covers
  Checklist for Stair Inspections
  Codes for Stairs
  Exterior stairs
  Fire Stopping for Stairways
  Guardrails on Balconies & Landings
  Lighting over Stairs
  Railings on Stairways
  Stair dimensions: width height &c
  Stairway headroom
  Stairway landings
  Step riser dimensions
  Step stringer defects
  Step tread dimensions
  Stair tread nose dimensions
  Wiinder stairs

...

Technical Reviewers & References

Search InspectAPedia

• Daniel Friedman - principal author/editor of the InspectAPedia^® Website
• Critique, contributions wanted: Contact Us to suggest corrections or additions to articles at this website, and if you wish, to receive online listing and credit as a contributor. Particular thanks are due to the many experts and also consumers who read and critique technical articles at InspectAPedia.com.
• Thanks to Alan Carson and Bob Dunlop, Carson Dunlop, Associates, Toronto, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education, publications, report writing materials, and home inspection services. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
• "The Elimination of Unsafe Guardrails, a Progress Report," Elliott O. Stephenson, Building Standards, March-April 1993
• "Are Functional Handrails Within Our Grasp" Jake Pauls, Building Standards, January-February 1991
• The Stairway Manufacturers' Association, (877) 500-5759, provides a pictorial guide to the stair and railing portion of the International Residential Code.
• Critique, contributions wanted: Contact Us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.

Attic & Basement Stair Inspection & Safety Concerns

We've had several reports of severe injury involving collapsing attic stairs, including involving home inspectors as well as occupants. Attic & Basement stair defects can be grouped by the stair type as we describe just below.

Basic information is just below. See Attic stairs for full details of this topic.

Conventional or home-made attic or basement stairways

Attic Folding Stairs or Pull-Down Attic Stairs

Watch for these common folding attic stair or ladder defects:

• Loose or missing bolts or hardware securing the attic folding stair hinges
• Loose or missing bolts securing the stair or ladder treads to the attic stair stringers or sides
• Attic folding stairs cut too long, causing a pressure point at the folding hinge, leading to split or broken attic folding stair stringers or sides
• Attic pull-down or folding stairs cut too short, perhaps not reaching the floor, leading to an unsafe "hanging" attic stair
• Attic folding stairs installed over an existing building stairway such as to a lower floor, attic folding stairs folding down onto or into the lower stairwell (unsafe to enter or exit)
• Attic pull down stair spring and hinge bent, loose, broken - risk breaking spring or hinge parts striking users pulling down the stairs
  
• Attic stair frame not properly secured to the ceiling rough opening

Balusters

Basic information is just below. See  Balusters & Railing Enclosures for full details of this topic. For more details about balusters (vertical spindles in railing construction) see details at Railings for a discussion of safety barriers along stairs, and Guards (railings on landings and open hallways, porches, screened porches, balconies that are more than 30" above floors or grade).

As our photo shows, a toddler (in this case very carefully held and supervised) can easily fall through open landing balusters or open balusters on a stairway.

We often see guards and railings enclosed using horizontal members or mesh or link fencing materials. Because a toddler can easily climb these materials, they are not safe for guard or railing enclosures and should not be used.

We also often see decks and porches more than 30" above ground level with no rail whatsoever, perhaps relying on the placement of plants or furniture to discourage people from stepping too close to the edge. Where building code enforcement was absent or lax we found a deck eight feet above ground with no railings at all. A local inspector opined that because the deck was not attached to the house (it abutted the house) it was exempt from building code enforcement.

Our opinion was that code exemption did not do much to reduce the falling hazard and that guards and railings should be provided regardless.

Exterior Stair Trip Hazards

We also often see trip hazards at exterior stairs and walks, details which may escape some building inspectors. It's common for gravel, dirt, or asphalt to settle inside of the step perimeter made of landscape ties such as shown in our photo. When the wood projection is 1/8" or more above the other walking surface (asphalt in this photo) it's a tripping hazard that should be corrected.

• Landscape tie stair edges raised above brick or stone interior - trip hazard (photo at above left)
• Landscape tie stair components rotted
• Masonry stairs frost-damaged, pitched (photo at above right, Justin Morrill Smith Historic Site, Strafford VT)
• Outdoor stairs should be designed so as not to accumulate water on the tread surface (Wet stair tread surfaces become slippery or icy)

Stair Guardrail, Newell Post & Baluster Specs & Defects

Guards or guard rails referred to in stair codes and specifications refer to the safety barrier placed along the open sides of a horizontal walking surface such as a landing, balcony, deck, or porch. The equivalent safety barrier placed along a stairway itself is discussed at >Railings.

Balusters for Guards & Railings

Stair Railing Specs & Defects

Railings in stair codes and specifications refer to the safety barrier along steps or stairs. Also see Guards for details about safety railings on landings and open hallways, porches, screened porches, balconies - horizontal walking surfaces.

Stair Handrail Dimensions & Shape

Examples of Stair & Landing Railing Defects

Stair Stringer Defects

The stair stringer is the diagonal supporting structure that carries the weight of the stair assembly as well as people using the stairs. You can see a stair stringer along the upper-edge of the set of stairs lying on their edge in our photo at above-right, after the stairs fell from the stair opening (our photo at above left) during a building renovation project. The stair stringer is secured to the structure at stair top, stair bottom, stair sides, depending on where there are building surfaces present.

Some common stair stringer defects we've found include:

• Stair stringer poorly secured to the top landing of exterior porches and decks
• Stringer loose, rotted, damaged, bowed, not secured to the building side wall where it should be, indoors or out
• Stringer improperly cut, deep notching, under-strength (see photo at Stair Riser Specifications & Defects)

Rotted stair treads or stringers: watch for rot in wooden stairs, especially at exterior entrances and decks. Where the stair stringer is mounted against a building wall water is often trapped, leading to hidden rot and sudden collapse.

Our photo shows rotting basement stair treads; from the stair top we could see that the entire stairway was twisting and in danger of sudden collapse. The sketch, courtesy Carson Dunlop, predicts stair rot exactly where it's found in our photograph.

Stair Riser Specifications & Defects

Bad Deck Stair Example: Nothing is right about the exterior stairs shown in our photo from a 1991 home inspection:

• This stair stringer is too-deeply notched and could split;
• The stair risers are too high, as our client is showing with our tape.
• The stair treads are too narrow.
• There is no railing and the height above ground is more than 36".
• The deck and platform railing is open with no balusters.

Stair Tread Specifications & Defects

Stair Step Treads

• Step tread depth (=> 10") (measured 12" from smaller side of irregular stair shapes such as triangular treads on curves or spirals)
• Step tread depth uniformity (<= 3/8" variation)
• Stair tread depth for winder stairs (>= 6" at smallest point)
• Stair tread uniformity for winder stairs at the 12" walk-line (<= 3/8" variation)
• Stair tread slope (out of level on walking surface) - (slope or "rise" must be <= 1 in 48) -- Source: IRC

Another Stair Code Example - Source BOCA 2001.

• Stair riser heights shall be 7 inches (178 mm) maximum and 4 inches (102 mm) minimum.
• Stair tread depths shall be 11 inches (279 mm) minimum. The riser height shall be measured vertically between the leading edges of adjacent treads. The stair tread depth shall be measured horizontally between the vertical planes of the foremost projection of adjacent treads and at right angle to the tread's leading edge.

Stair Step Tread Nose

• Tread nose projection past vertical riser below (3/4" to 1 1/2") required on stairs with solid risers (exceptions are below)
• Tread nose projection uniformity (<= 3/8" variation)
• Tread nose curve radius (=< 9/16")
• Tread Nose not required if tread depth is => 11"
• Tread Nose not required on open stair treads (open riser

Another Stair Code Example - BOCA 2001.

• Stair tread nose projection missing or wrong dimension: (falling hazard on descending) or tread nose extends out too far over tread (risk splitting off or trip on climbing up). Example: A nosing not less than 0.75 inch (19.1 mm) but not more than 1.25 inches (32 mm) shall be provided on stairways with solid risers where the tread depth is less than 11 inches (279 mm). - BOCA 2001.

Examples of stair tread defects

Stair Platform or Landing Specs & Defects

Common Stairway & Railing Specifications, & Trip or Fall Hazards

Stairs that are Curved or Angled, & Winder Stairs

Notes Comparing Building Codes Specifying Stair & Railing Requirements         

Sample excerpts of sources which a building code compliance inspector would be expected to cite in support of requiring a properly-designed, properly-secured guard rail include but are not limited to the citations below.

International Building Code 2000 (BOCA, ICBO, SBCCI)

1003.3.3.4 Stairway landings. There shall be a floor or landing at the top and bottom of each stairway. The width of landings shall not be less than the width of stairways they serve. Every landing shall have a minimum dimension measured in the direction of travel equal to the width of the stairway. Such dimension need not exceed 48 inches (1219 mm) where the stairway has a straight run.

1003.3.3.11.3 Handrail grasp ability. Handrails with a circular cross section shall have an outside diameter of at least 1.25 inches (32 mm) and not greater than 2 inches (51 mm) or shall provide equivalent grasp ability. If the handrail is not circular, it shall have a perimeter dimension of at least 4 inches (102 mm) and not greater than 6.25 inches (159 mm) with a maximum cross-section dimension of 2.25 inches (57 mm). Edges shall have a minimum radius of 0.125 inch (3.2 mm).

100333.11.4 Continuity. Handrail-gripping surfaces shall be continuous, without interruption by newel posts or other obstructions.

1607.7 Loads on Handrails, guards, grab bars and vehicle barriers

1607.7.1.1 Concentrated Load. Handrail assemblies and guards shall be able to resist a single concentrated load of 200 pounds (0.89kN), applied in any direction at any point along the top, and have attachment devices and supporting structure to transfer this loading to appropriate structural elements of the building.

1607.7.1.2 Components. Intermediate rails (all those except the handrail), balusters and panel fillers shall be designed to withstand a horizontally applied normal load of 50 pounds (0.22 kN) on an area not to exceed one square foot (305mm2) including openings and space between rails.

BOCA National Property Maintenance Code 1993:

PM-305.5 Stairs and railings: all interior stairs and railings shall be maintained in sound condition and good repair.

Commentary: Handrails, treads and risers must be structurally sound, firmly attached to the structure, and properly maintained to perform their intended function safely. During an inspection the code official should inspect all stringers, risers, treads, and handrails.

PM-305.6 Handrails and guards: Every handrail and guard shall be firmly fastened and capable of supporting normally imposed loads and shall be maintained in good condition.

Commentary: This section provides for the safety and maintenance of handrails and guards. See Section PM-702.9 for additional requirements.

PM-702.9 Stairways, handrails and guards: Every exterior and interior flight of stairs having more than four risers, and every open portion of a stair, landing or balcony which is more than 30 inches (762mm) high, nor more than 42 inches (1067mm) high, measured vertically above the nosing of the tread or above the finished floor of the landing or walking surfaces. Guards shall be not less than 30 inches (762mm) high above the floor of the landing or balcony.

Commentary: Handrails are required on all stairs more than four risers in height. Handrails cannot be less than 30 inches nor more than 42 inches above the nosing of the treads (see Figure PM-702.9).

Guards are required on the open side of stairs and on landings and balconies which are more than 30 inches above the floor or grade below. The guard must be at least 30 inches above the floor of the landing or balcony. Guards are to contain intermediate rails, balusters or other construction to reduce the chance of an adult or child from falling through the guard. If the guard is missing some intermediate rails or balustrades, it is recommended that the guard be repaired to its original condition if it will provide protection equivalent to the protection it provided when originally constructed.

Stair Inspection Checklist & Form

Notes to Table of Stair & Railing Defects/Checklist

...

Technical Reviewers & References

Search InspectAPedia

• Daniel Friedman - principal author/editor of the InspectAPedia^® Website
• Critique, contributions wanted: Contact Us to suggest corrections or additions to articles at this website, and if you wish, to receive online listing and credit as a contributor. Particular thanks are due to the many experts and also consumers who read and critique technical articles at InspectAPedia.com.
• Thanks to Alan Carson and Bob Dunlop, Carson Dunlop, Associates, Toronto, for permission to use illustrations from their publication, The Illustrated Home which illustrates construction details and building components. Carson Dunlop provides home inspection education, publications, report writing materials, and home inspection services. Alan Carson is a past president of ASHI, the American Society of Home Inspectors.
• "The Elimination of Unsafe Guardrails, a Progress Report," Elliott O. Stephenson, Building Standards, March-April 1993
• "Are Functional Handrails Within Our Grasp" Jake Pauls, Building Standards, January-February 1991
• The Stairway Manufacturers' Association, (877) 500-5759, provides a pictorial guide to the stair and railing portion of the International Residential Code.

Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

STAIRS, RAILINGS, LANDING INSPECTIONS, CODES
  Attic stairs
  Balusters & Railing Enclosures
  Basement Stairs & Walkout Covers
  Checklist for Stair Inspections
  Codes for Stairs
  Exterior stairs
  Fire Stopping for Stairways
  Guardrails on Balconies & Landings
  Lighting over Stairs
  Railings on Stairways
  Stair dimensions: width height &c
  Stairway headroom
  Stairway landings
  Step riser dimensions
  Step tread dimensions
  Stair tread nose dimensions
  Wiinder stairs

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