How to build steps at the back of your house: A blog about building some concrete steps.

It took me a long time to figure out how to build these stairs, because I wanted them to be both good-looking and reasonably easy to make. I finally decided on a design inspired by the concrete stairs you often see in public buildings and office parks.

In theory it should be easy enough to adapt my design for stairs with three or more risers. But in practice if you have that many steps you probably want a permanent, immovable structure made of cinder block or something like that, so you should probably consult a professional. The instructions below are just for two-step stairs like mine.

I’ve been wanting to build some concrete steps at the back of our house for several years now, but never seemed to get around to it. Well, this past weekend I got inspired and decided it was time to start tackling my honey-do list.

So let’s get started!

I installed a 12×12 concrete slab back in October 2007, so I’ll be using that as my base for the steps. See how I built the slab: Preparing for a Concrete Slab.

Here’s a look at the area where the steps will be built.

These are the steps that I built at the back of my house. The first step was to remove the old rotting ones. The new ones are made from concrete, with rebar reinforcement inside.

Above you can see the formwork or “mold” that I used to pour the concrete steps. I made this out of scrap wood, probably around $10 worth of wood total. It’s not pretty, but it is strong and it gets the job done.

I started by sinking some 2×4 posts into the ground and then attaching them together with more 2×4 pieces to make a square frame in which I could pour the concrete.

The concrete is poured in layers, each layer is tamped down with a long piece of 4×4 wood to remove any air bubbles and help consolidate the concrete.

After pouring all four steps, I smoothed off the edges with an edging tool, which looks like a large putty knife with a handle attached at a right angle.

I did one step per day for four days, waiting 24 hours between pouring each step because it takes about 24 hours for concrete to reach 90% of its full strength.

I have a couple of projects going on around the back of my house. One is to build a deck and the other is to build a concrete block retaining wall.

My wife has been wanting some steps down our hill for a while so this seemed like the perfect opportunity to knock it out and enjoy our new tools at the same time.

Steps:

I grabbed a pencil and some graph paper and started designing the steps. The first thing I did was determine how many steps I would need and where they would be placed.

Next I determined how wide I wanted them to be, how much tread I needed, how much riser height was comfortable, etc. After some calculations I saw that my rise was going to be too great for just one step, so I decided that two were needed with a landing in between. From my drawings it looks like the overall rise of both steps is about 35″. In order to make sure that everything was square and level, I used two pieces of string as guides. This worked out very well as long as you remember to keep your strings pulled tight!

I ended up putting 2×4’s into the ground as temporary forms to hold up my concrete. My forms were 4-1/2″ wide

The first step to building your steps is to work out how many you are going to need. We wanted three steps so that there aren’t big gaps between the treads.

The size of the concrete blocks we used was 440mm x 215mm x 100mm. The steps will be 440mm wide, with a rise of 100mm and a run of 215mm (the horizontal distance from the front of one tread to the front of the next).

The foundation for our steps has been dug out, compacted and ready for pouring. If you are building onto an existing foundation then you’ll have to dig a trench down the side of it or chisel through it.

We used quick-setting cement in our footings because we were in a hurry and it’s not going to be taking much weight. We mixed it with water according to the instructions on the packet, and then poured it in until it was level with the top of the foundation. We also put in some reinforcing mesh (re-bar). We waited two days until it was set before continuing.

The need for some back steps became evident when I was faced with the prospect of shoveling snow off the back porch. The porch was built without any steps, and the previous owner had used boards laid across the concrete to reach the ground. I have a bad back and this wasn’t an option for me.

The first step was to figure out how many steps we needed, and how much height they would need to cover. It’s always good to know your starting point! We decided on three steps, so I measured from the bottom of the porch floor to the ground, which turned out to be about 32′. To find out how tall my steps would need to be, I divided 32′ by 3, which means that each step would be about 10 1/2″ high.

The job ended up being more complicated than expected. See my original post for the full story, but I ended up having to build a form and then pour a layer of concrete on top of the ground, then build another form and pour those steps. The idea is that this will keep the ground from eroding away from under the steps over time, and also help prevent frost heaves from pushing them out of level in the winter.

The first thing I did was dig out about 30 inches behind the existing steps. Then I built a form (just 2x4s nailed together) and filled it with concrete to make a sort of foundation for the new steps.

I waited about a week for that to dry, then cut down the old brick steps by about 8 inches so that they were flush with the new concrete foundation. Then I built another form around that:

With the forms built and ready to go, I mixed up some quick-set concrete and poured it into place. I had done this a few times now so it wasn’t too bad:

After leveling out each step as best as I can, all that’s left is to wait for it to dry! It says on the bag that you should let it sit overnight before walking on it, but