Hanging a basement stairs....

[Michael Donahue]

I need to rebuild my basement stairs and I'm not quite sure how to hang them. As I understand it, you don't put the first tread even with the top floor, but rather you make it one rise lower. This is how the old stairs are built now. Between the floor and the first tread there is a vertical 2x8 almost like a header that's inset just under the floor. Is this piece meant to stay there? If so, how do I mount my new stringers to it if it's in place? Would I instead attach a similar piece to my stringers and then mount all of that? Sorry the picture isn't that great, but it gives you the general idea.

Two more questions if you don't mind! :D

1. Should I anchor the bottom into the concrete floor some how?

2. I'm in northern CT just by the Mass border, so my borgs sell green doug fir and those a few towns north of me sell KD spruce for framing lumber. I've always used the spruce 2x4's for my projects because I didn't want wet lumber in an existing wall or on my workbench, for example. But some people swear by the fir. Which would you use for the stairs?

[Anthony Watson]

Michael,

There are a variety of ways to hang the upper end of the stair stringers, depending on what kind of support is available on the upper end, and how much distance you have for the stairs. The three options I would consider:

Option 1: Make the first tread the same height as the top finished floor. Then attach the stringers to the floor framing with joist hangers. Bolt the hangers to the floor structure first, then slip in your stringers and nail from the sides. Of course, while this is easy to implement, it adds the width of the first tread to the total run of the stairs. This may be a problem if the stairs fit in a confined stairwell, where you may run into headroom problems.

Option 2: If you have a wall under the upper end of the top finished floor, you can use the same technique as above, just drop the first tread down the height of a riser. Bolt a ledger board to the studs, and cut the stringers back the depth of the ledger. Then attach the stringers with joist hangers. I used this option for the basement stairs at my in-laws, where I bolted a pressure treated ledger board to the concrete wall.

Option 3: If there's no wall under the upper end, and you have limited distance and/or headroom in the stairwell, you can use metal straps for each stringer. Nail a 16" or longer metal strap to the bottom of the stringer, bend it up flush with the end of the stringer, then nail it into the floor framing above. This is the approach I used on the stairs in my own garage. It's strong, and works well.

As for the wood to use, since this is a basement, I would use pressure treated 2x12's to frame my stringers. If the top is fastenend securely you wouldn't necessarily need to anchor the bottom end, but adding a cross brace or metal "L" brackets and anchoring into the floor would provide a bit more stability, especially side to side. Alternatively, you may be able to brace the stairs into a side wall?

A 7 to 7.5" riser is about the ideal, but you can increase or decrease that up to an inch or so as long as you keep the ratio of the stair treads and risers to something between 17 and 18. For example, 10-1/2" treads and a 7" riser add up to 17-1/2", or an 9-1/2" tread with an 8" riser would also be 17-1/2". Keep in mind, building codes are very strict about stairs, and most areas don't allow 8" or steeper risers anymore. Stairs that steep aren't very comfortable anyway.

Anthony

[Matt Ocel]

Michael -
Is that 2 risers? Can't tell by the pics.

Anthony has some good ideas.

Or

If you had a little better pic I could dial you in on what I would do.

[Michael Donahue]

Michael -
Is that 2 risers? Can't tell by the pics.

Anthony has some good ideas.

Or

If you had a little better pic I could dial you in on what I would do.


I can't find my camera so I can't get a better pic :( What you're looking at anyway on the top is the edge of the laminate in the hallway just outside the basement door, then a drop to the first tread. The riser appears to be nothing but a 2x8 nailed between the joists, and it's located so it's just flush with the subfloor in the hallway.

[harry strasil]

http://img.photobucket.com/albums/v81/irnsrgn/odd/staairs.jpg

[Matt Ocel]

Michael -
You can do as Anthony stated by using straps(if you have accsess from underneith or behind.
I would take off the existing 2x8 and install a 2x10, cut new stringers, and use 2x4 "pinch blocks mounted on the 2x10 between the stringers. Then either toenailing(or toe screwing) or using a simpson stair stringer hanger.
My outside stringers would also be cut to set my tread onto, and not on a cleat as shown on the pic.

Since you are replacing an existing stairway, you should be able to use the same rise and run, but if you have enough room ie headroom, landing area, I would build the new stair to comply to local building codes. Typically run = not less than 10" and rise = not greater than 7 3/4".

[Richard Wolf]

If you are copying the design of the existing staircase, open risers, you should use a riser on the top step. If you screw the top riser into the stringers, you can then screw the top riser into the existing header.

Richard