How To Allow For Minimum Forward or Backward Movement On Exterior Stairways - Building Ideas
I recently had a viewer ask me how to allow for minimum forward or backward movement on exterior stairways. I've never had to deal with this problem myself, but I can offer a few suggestions.
The first thing to keep in mind is that the connection between the stairs and the top landing or porch needs to be tight. You don't want the stairs to pull apart an inch or two while you're walking up them.
There are a few ways to achieve a tight connection at the top. One way is to use a ledger board that is nailed to the framing members. Another way is to use nails that go through the treads and into the framing members.
The standard construction for stairs is to have the stringers sitting on top of a piece of treated lumber, which is then sitting on top of concrete. If the stairs are just sitting on top of the soil, you don't need to worry about this as much, because they will move without any problems.
My first suggestion is to notch the framing plates where they are attached to the concrete foundation. This will allow the stairs to move in either direction without creating enough pressure to rip the stairs apart at the top or the bottom. However, this may not be enough. You may also need to create a frictionless connection at the bottom by applying grease or something similar.
Another suggestion is to separate the stringers from the framing plates so that they can move independently. This can be done by using a metal bracket with a slot cut into it. This method may be more difficult than the first method, but it may be more effective.
Finally, I would recommend moving the framing plates back a little further so that they don't end up forcing the risers away from the stringers.
Bonus Stair Building Engineering Tips
Local building approval might be required or contact a structural engineer if needed, before making any changes to your stairs.
Make sure that your stairs are properly anchored to the foundation.
Use the correct materials for your stairs, such as pressure-treated lumber.
