While adding staircase angles under the treads of the stairs that go down to our unfinished basement, I noticed that the "angle braces" that connect the top of the stringers to the ceiling joists are nothing more than what looks like door hinges (see pic). Assuming that is unacceptable, I want to replace them with proper angle braces. (FYI, in addition to these braces, the stringers are also fastened to the joists with #14 3-1/2" screws.) Would the Simpson Strong-Tie ML26Z (https://www.strongtie.com/deckconnectors_decks/ml_angle/p/ml) be a good choice? That is a 12 gauge 2x2x6 angle, which I would connect with the specified 1/4"x1-1/2" SDS Heavy-Duty Connector screws. Thanks.
What is the proper angle brace for this stair stringer to joist?
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either a right angle connector plate, otherwise known as. L-30, L50, L70's.. there numberd based on what size lumber they will fit to.. L30 works on 2x4,, L50 on 2x6 and so on
With the stringers ending against a wall (?), somebody put the hinge there thinking existing connections may not be enough. You must look carefully. The hinge is more or less useless since the small screws don't have enough bite into the header.
If you replace with similar angle type, you must use 1/2" bolts, at least 3 and the bolts must be in the center of the lumber. The top of stringer to header or other frame connection is usually done with fasteners that are driven in horizontally to resist the drop. These fasteners must have good shear strengths. For example, the drywall screws that can snap off easily at the neck are no good.
If you replace with similar angle type, you must use 1/2" bolts, at least 3 and the bolts must be in the center of the lumber. The top of stringer to header or other frame connection is usually done with fasteners that are driven in horizontally to resist the drop. These fasteners must have good shear strengths. For example, the drywall screws that can snap off easily at the neck are no good.
Thanks. I went ahead and replaced the door hinges with ML26Z angles, each held in with eight 1/4"x1-1/2" SDS screws. It may not have been necessary, but given when I first started working on these stairs the stringers were only fastened to the joists with nails, plus the door hinges, I do feel better about it. And in another thread, at joecaption and jlhaslip's suggestion, I added Simpson TA9Z staircase angles under the treads to fasten them to the stringers, since they were also only fastened together with nails which kept starting to pull out.
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