Retaining Walls

The Mistake I Made Installing Pressure-Treated Timber Stairs


Math Errors

So I’ve talked to you in the past about some of the difficulties and challenges of building stairs. They’re not easy. From a mathematical standpoint, it works out just like rise over run. You look at the hillside behind me and you say, “OK let’s say we’ve got 15feet of height differential.  We’ve got a 6-inch stair, so that’s going to equal 30stairs.” Then we figure that at the depth 12 inches per stair, you’re going to have about 30 feet. You measure, “do we have 30 feet?” And it all works out on paper. But when you get out in construction, sometimes things go wrong.  So, today I want to show you something that didn’t go right that we’re about to fix and what happened and how it could have been prevented.

Right here we started building the stairs as we normally do. And the one thing I want to point out is these for 7 or 8 stairs look fantastic from an aesthetic standpoint.  They’re solid and they’re strong.  The problem is that they’re too deep. We’ve got 3 ½ timbers exposed. Each timber is 6inches, so that gives you roughly about 20inches tread depth. So we get up about 7 stairs and we’ve run out of Earth. We’re too deep into the earth.

Hillside Woes

If we keep going up like that we’re going to be basically excavating this entire hillside, and here’s part of the result of that is that gigantic pile of dirt. So, in the end, we made a mistake. We screwed up. We didn’t calculate in how correctly, and that happens. So what do we do? Well we’ve got to go back and fix it. One of the thoughts was we could transition this to a set of deck stairs, but you decide it’s not the right feel for the project. You’ve got to go back to the beginning, take out the stairs, and rebuild them.

If we keep going up like that we’re going to be basically excavating this entire hillside, and here’s part of the result of that is that gigantic pile of dirt. So, in the end, we made a mistake. We screwed up. We didn’t calculate in how correctly, and that happens. So what do we do? Well, we’ve got to go back and fix it. One of the thoughts was we could transition this to a set of deck stairs, but you decide it’s not the right feel for the project. You’ve got to go back to the beginning, take out the stairs, and rebuild them.

Fix Mistakes

In this case, we actually don’t have to take up the stairs, and that’s the good news because this repair is going to go from about a day long repair to get us just back to where we were to probably about 4-5hours. You can see if we add the stairs in correctly 2 timbers per stair. We’re going to take this timber out, pull it forward, and we’ll have 2 timbers in a stair. Then we can just fill in. We are basically abandoning the rest of these timbers below, and just creating more strength to the structure. So, we lose a little bit of material, but we gain a ton in time.

So I want to say that not everything always goes perfectly on the job.  But when it doesn’t, go back, take your time and figure out what went wrong.  How can you avoid this in the future by doing a little bit more of the math work upfront? Which frankly on this project we didn’t do it down to an exact. We looked at it and based it off of our experiences on other projects and did not account for just how incredibly steep this hillside is.

Save Headaches

So, had we done that we probably would have saved ourselves a headache. But you learn a few lessons the hard way sometimes, just as we did here. But we won’t let that happen again in the future.  During the entire process, keep the customer involved and keep the lines of communication open. You acknowledge what you should have done differently and then you just do the right thing.

So, here’s our retaining wall. This is going to look fantastic when it’s done. We’re going to get rid of this dirt today. We’re going to haul it out to our shop and we’re going to use it for another project. Then we’re going to come back and say we’re going to put sod in. I expect all that to be pretty close to completion by this afternoon which will be about a 9-hour day working with 2 guys out here.


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