TA 10-1/4 in. 12-Gauge ZMAX Galvanized Staircase Angle

First when using simpson strong tie connectors always recommend downloading their full catalog: https://www.strongtie.com/resources/literature/wood-construction-connectors-catalog If you look at the catalog page for these connectors it says that they take 1/4" fasteners. Looking at a threadsize chart (this one would work: https://www.engineersedge.com/screw_threads_chart.htm ). you will see that 1/4-20 and 1/4-28 screws have an external diameter of 1/4". 1/4-20 is much more common. So I would recommend 1/4-20 bolts of the correct length and large fender washers (to better distribute the compressive force of the nut and bolt) with 1/4-20 nuts.

The load capacity depends which direction the TA9Z is installed - with 2 fasteners to the stringer and 3 to the tread it has a capacity of 500 lbs; with 3 fasteners to the stringer and 2 to the tread it has a capacity of 750 lbs. The loads are based on Douglas Fir or Southern Pine lumber and the TA9Z is to be installed with 1/4" x 1 1/2" SDS screws. The TA9Z will not bend over time as long as it is not loaded beyond its rated capacity. Thank you!

So you would use these brackets when you want to have solid stringers as opposed to cut stringers for your outdoor stairs. Note that code allows you to use only two solid stringers on either side of the tread and these brackets if you use at least 2x6 Pressure treated boards for the tread and the length of the tread is no more than 36 inches. To your question, I used two 2x6 boards for the tread. Of course, don’t forget to have at least a quarter inch gap between the two boards to allow water to flow. Then I used a 2x6 board as a riser . The top tread overhangs the riser by ~.5”. The riser is screwed directly to the back side of the bottom tread and attached to the top tread using blocking. I did not want to have Screws heads that could collect water On the top tread.

We can only support the installation as it was designed/rated. With the vertical leg up, the stair tread would need to be a bit shorter to allow for the screw heads, which would bring the edge of the tread closer to the fastener than it was designed/rated to be. Thank you!

Please check with your local building department for local code acceptability. Thank you!

Probably shouldn't be, we removed an older set that had been installed with 12' treads and some of the over hanging boards had split of along the grain line in front of the brackets. There is a longer version that can be used.

I used 1" deck screws into my 1" thick composite board decking.

Simpson Strong tie sells a specific screw for this connector. They are called “strong Drive SDSheavy duty connector screws”. Of course, if this is an exterior application get the exterior grade screws. Highly recommend downloading the Simpson Strong tie catalog as a PDF. It’s quick to search but it does take a little bit of thinking to find the right connectors and fasteners. Home Depot can pretty much can get you anything in that catalog. Even though the screw package says that pre-drilling is not required, I highly recommend pre-drilling a pilot hole for this and any screw fasteners that you use.

Yes, you can use this for interior stairs.

1/4 inch