basement framing with metal Studs Best way to fasten them to the floor

Question

I'm planning on framing my basement with metal stud (2-1/2" x 10' 25-Gauge Drywall Interior Metal Stud). I have XPS foam 2" attached directly to the concrete wall. I plan to leave a 1/2"-1" air gap between the stud and the XPS and the Stud. I will use a sill sealer under the metal track.

I'm not sure of the best way to attach the bottom plate to the concrete floor. I was debating on using tap con screws or a power actuated ramset. Would the nail go through the metal stud ? My guess is the metal stud will stop the head of the nail. I've seen the nails get shot 1/4 inch into lumber before. I would prefer the ramset for speed. Also I'm debating if I should also apply construction adhesive since I'm using the Sill sealer. I would have to apply it to the bottom and top not sure if it would help out.

Answer 1

The U-shaped metal track that goes along the concrete floor to hold the studs is typically fastened to the floor with the short concrete nails put in place with the ramset method. The vertical metal studs are then put in place and they are attached to the up turned sides of the metal track using sheet metal screws. The screws most often used are ones that self pierce the metal and thread themselves in to secure the studs.

Note that the metal track and the metal studs are rather thin and offer little or no resistance to the placement of the ramset concrete nails.

Answer 2

To avoid blasting through thin metal, rip a board to the width of the inside of the track and so that it can be in direct contact with the bottom of the track, and cut it into short sections making sure the pieces are short enough in length so as to not intrude, or get in the way of the placement of the studs. I would use plywood because it is less likely to split out than 2 x material. With the plywood in place drill a 1/4" diameter hole with a masonry bit through the plywood and through the floor to a depth sufficient enough length to be able to drive two 16d or 12d nails onto the whole at the same time. This is important because the thickness of 2 nails side by side should be slightly wider than the diameter of the whole, and will cause the nails to bind up as you are driving them. This works on the same principle as a metal-hit anchor. https://tinyurl.com/ybvzeb7r I would place a board every 3 feet. No need for fancy fasteners or glue with only the cost of a few nails.