basement stairs replacement?

Question

How do I calculate the cutting of new stairs? My stairs are made of 1x4's for the treads and the stringers are 1x6 without the zig zag cuts. The treads rest on 1x2's nailed to the 1x6's. No center stringer either. The treads are currently 5" to 6 1/2" with risers of 8" and 9". Then it has a landing near the top with landing also being 1" plywood. I have to back down the stairs because I'm afraid of falling. The bottom step broke and I did a pirouette while holding with my right arm to the rail made of casing. Brilliant save. I'm a professional at falling down stairs. This would be about my seventh fall. Also, when they cut the beams for the hole for the stairs they did not reinforce the beams with joist hangars or anything.

Answer 1

Not sure how small your foot is or how long your legs are, but for me that tread/rise you've got going is wacky. Not to mention it might not meet code. The IBC specs a maximum rise at 7-3/4" while others are no more than 7. I feel that treads are comfortable at 10" with a rise between 6-7." (don't forget about adjusting for finished flooring to the bottom/top stairs) Also, most building codes allow for 1/4 to no more than 1/2" difference between each riser. Could be why you're falling down those stairs so much!

Check with your local building code to see what they require including reinforcing the beams. Here's a nice looking site for help with the calculations: http://www.bobvila.com/HowTo_Library/Stairbuilding_Basics-Stairs-A1981.html

Answer 2

Looks like Cheech and Chong built your stairway! There is a least a couple of ways. Here's a calculator that can work out any stair arrangement. www.blocklayer.com/Stairs
Or you can use prefab metal brackets from ezstairs.com to make the job simpler. Also use 2x12s for the stringers and 2x10s for the treads, and you can put away your ballet shoes for good! Hope this helps.