Pier installation details (C) Daniel Friedman Deck Stair Planning
Deck Design-Build Online Guide

InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Start here to plan for the construction of deck or porch stairs. This article defines basic stair terms: rise, run, stringer, tread and othe rcomponents. We describe options for different types of stair supporting stringers and we give advice about choosing lumber to build deck stair stringers, treads and risers.

This three-part deck stair article series describes how to build exterior stairs used at decks & porches. We include critical safe-construction details for stairs used to access decks and porches, including avoiding unsafe deck stairs and railings.

Green links show where you are. © Copyright 2017, All Rights Reserved.

How to Plan for the Construction of Deck or Porch Stairs

Stair gauge in position on a wood scrap (C) Daniel Friedman

Stairs are primarily functional elements, but they can also have a large impact on the visual appeal of a deck. They can be prominent and grand, or minimal and understated.

Sometimes the site and deck style dictate the type of stairs you need; at other times you have a great deal of latitude in the design. Either way, stairs can be a major component of your deck’s appearance, so take some time to find a style that suits you.

One of the most visible parts of a stairway is the railing. Whether you are required to include a railing or just want to have one, be sure to include the railing in your overall design.

Likewise, lighting the stairs and the landing is an important safety consideration and may be required by your local building codes.

Stairs with three or more steps should have a railing on at least one side. The railing must be located 30 to 38 inches above the nosing on each tread. Railing posts must be spaced no more than 5 feet apart, and balusters must be spaced no more than 4 inches apart. Deck stairs are frequently built without risers, but codes often require them, and many people think stairs also look much better with risers.

To help keep children or pets from falling through, the triangular area formed by the tread, riser, and railing must not be large enough to permit a 6-inch ball to pass through. The stringers should be attached to a concrete pad, and the stairs and landing may have to be illuminated.

Stair Support Components: definition of Stair Stringer

The basic framing components of stairs are stringers, also called carriages. Typically made out of 2 X 10s or 2 X 12s, stringers are often cut to create level surfaces for treads and plumb surfaces for risers. Stringers can also be solid boards with brackets attached for the treads. Stringers can be attached to the deck framing and the landing pad with angle brackets.

The treads and the risers are related components. Treads are the part you walk on. Risers, if any, fill the vertical gaps between treads.

How to Determine the Stair Dimensions: definition of stair rise, stair run, stair tread dimensions

Stair rise and run sketch (C) Daniel FriedmanRegardless of how you plan to build your stairs, you must first calculate the overall dimensions. In the terminology of stair building,

Details about how to calculate the stair rise and run are given at STAIR RISE & RUN CALCULATIONS.

Stair Stringer Options

Stair stringer options (C) InspectApedia Carson Dunlop AssociatesMuch of the variation in stair styles boils down to how you handle the stringers. The easiest stairs to construct use solid stringers with metal brackets supporting the treads, and no risers. This style is best used on short, narrow stairs or where risers are not required.

Cut stringers involve more effort, but they result in stronger, more attractive stairs.

They also provide a solid vertical surface for attaching risers. If you want to build stairs with cut stringers, but prefer the profile of solid stringers, you can add a decorative trim board.

Illustration at left provided courtesy Carson Dunlop Associates.

Deck Stair Landing Choices

The landing is a very important consideration for any stairway, since it provides a firm surface for the first step up or the last one down. On decks, the landing also serves as support for the stringers. The best type of landing is a concrete pad. With careful planning it is possible to pour the pad while you are working on the footings and piers, but it i% safer to wait until the decking is installed.

The bottoms of the stringers are usually attached to the landing pad with angle brackets. Alternatively, the stringers can be cut to fit over a 2 X 4 kickboard fastened to the pad. For short stairs, you may be satisfied with a landing of compacted gravel; attach two 2 X 4s across the bottoms of the stringers to distribute the load.

Choose the lumber size

Short deck stairs can often be made with 2 X 10 stringers, although many builders routinely use 2 X 12s. The critical determination is the minimal width left in the board after the notches have been cut. If this width would be less than 4 inches you should use wider boards for the stringers.

To determine the length of boards you will need for the stringers, use your framing square and a tape measure, and assume that 1 inch on either represents 1 foot. On many squares, one edge of the square is graduated in twelfths of an inch to facilitate this calculation.

Figure the total rise and total run in terms of feet and inches, then mark the total run on the long side of the square and the total rise on the short side.

Determine the distance between the marks with a tape measure to determine the minimum length of the boards you will need.


Continue reading at DECK STAIR BUILDING START or select a topic from closely-related articles below, or see our complete INDEX to RELATED ARTICLES below.



Suggested citation for this web page

DECK STAIR PLANNING at - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.


Or use the SEARCH BOX found below to Ask a Question or Search InspectApedia


Frequently Asked Questions (FAQs)

Click to Show or Hide FAQs

Ask a Question or Search InspectApedia

Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.

Search the InspectApedia website

Comment Box is loading comments...

Technical Reviewers & References

Click to Show or Hide Citations & References

Publisher's Google+ Page by Daniel Friedman