If you are going to use anchor screws (Tapcons)...

You need to contact Concrete Fastening Systems. Period.

Home Depot carries Tapcons (the alternative to using a Ramset to attach 2x4s to concrete, brick or masonry) but at a cost of $.20-$.25 cents each, and in two different stores I went to, they only sold them in boxes of 75, and they didn't have them in the length we need for our project.

In general, you add the depth of materials you are fastening to your concrete/brick/masonry and add 1" for penetration into the surface. (We, by the way, will be going overboard and also caulking the 2x4 furring boards to the surface before drilling for the Tapcons.) In our case, we have .5" of plaster and 1.5" of lumber to attach to our brick exterior walls. This means we'll be using a minimum 3" Tapcon. We found them in 3 1/4". We chose the 3/16" flathead screws so we wouldn't have to worry about the hex caps messing with the drywall we'll be laying over top.

We'll need about 500 of them to furr out all of the exterior walls at 2' intervals and prepare them for the closed cell spray insulation (more on that later). If we bought them at Home Depot we'd be looking at $110, and then we'd have to buy the drill bits ( you need to pre-drill the holes before using your hammer drill to insert the Tapcons) at about $2.50 each (replacing them about every 100 holes drilled.)

So why go to Concrete Fastening Systems (in Cleveland, OH) or online at www.confast.com? Because my 3/16" x 3-1/4" Flat phillips head Tapcons cost me only TEN CENTS EACH. And here's the kicker: I ordered them on Tuesday. They arrived Wednesday afternoon. Shipping was about $11.

And there was a bright and shiny new drill bit in each and every box, Free. Fast and cheap. Gotta love 'em.

So spread the word... Our demolition contractor said he used a Ramset because Tapcons were too expensive. Heh. Not any more.