Ask the Builder

Ask the Builder: Consider upkeep when deciding on materials for outdoor stairs

By Tim Carter
Saturday, November 28, 2009

Q: I need to build some custom stairs outdoors. I was thinking of using stone, but I am open to other ideas. I was thinking of using custom iron stairs, but I don't know how to weld or fabricate them. Can you give me a few suggestions about what it takes to build a custom staircase? -- Laura S., Locust Valley, N.Y.

A: I can relate to your confusion. There are so many materials you can use to build outdoor stairs that it can be hard to make a final decision.

I recommend that you think about how much maintenance you are willing to do. If you choose wood or metal, you'll have to take care of them over time. Granted, you can select a metal that doesn't corrode or a special steel that develops a patina of rust, but these are probably way beyond your budget.

Natural stone, brick and even concrete are materials that should not require any maintenance in your lifetime other than a periodic cleaning to remove dirt, algae and possibly moss that can make the stair treads slippery.

I've built outdoor stairs from many materials, including brick, fieldstone, flagstone, wood and metal. I'm partial to any natural stone and brick, as they seem to blend better with plants, bushes and trees. What's more, they're nearly maintenance free. I love the fact that I just have to clean them periodically.

I can tell you that you only want to build the stairs once. This means you have to plan carefully, making sure that your stairs connect seamlessly between the different levels in your yard. Make sure the stairs meet all local building codes with respect to the sizes of the treads and the risers. People trip and fall on steps every day. Don't underestimate the importance of keeping the stairs code-compliant. Contact your local building department for a copy of the section of the building code that deals with stairs. You may be able to get this online at no cost.

Building codes change every few years, but I've discovered that the most comfortable combination of rise and run happens to be a rise of 7.5 inches and a run of 10 inches. This simply means that each tread on the stairs is 10-inches deep and the vertical distance between the top surface of each tread and the landing above or below is 7.5 inches.

If you decide to use thinner natural stone or brick, you usually apply these on top of a poured-concrete base. This means the concrete must be poured to mimic the finished profile of the stairs, but be sunk into the ground the thickness of the stone or brick covering plus the thickness of the mortar you will use to bond the stone or brick to the concrete. Be sure the concrete has a rough texture, and make sure to place reinforcing steel in the concrete so it doesn't break apart over time.

If you decide to use solid slabs of natural stone, you just need to make sure they are the correct size so that, when stacked one on top of another, they create a rise and run that satisfies the building code. You'll need lots of help with these, as each piece of stone will weigh hundreds of pounds.

Avoid shortcuts in the planning process. Take your time and draw up what you plan to do. I urge you to do the math in your yard to make sure the stairs are going to work and that all the dimensions are correct.

Tim Carter is a columnist for Tribune Media Services. He can be contacted via his Web site at http://www.askthebuilder.com/printer_Submit_Question.shtml.


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