Thanks. I may end up with some sort of alarm system anyway, so this was helpful. In the end I went with (single) sliders, which was originally at the bottom of my list, almost out of consideration. Got my ventilation, window treatments, curb appeal and there are actually many more add-on security options for sliders than hoppers or awnings. The awnings were just too pricey. Getting estimates now. Started with Home Depot's @ Home Service and got a quote of $3030 for American Craftsman six sliders and one hopper (my egress in the laundry room.) I know there's a real love 'em or hate 'em thing with HD but I did have some minor kitchen work done a while back and had an excellent installation experience. ~Jacy

On new homes I've built, I either used poured-in place windows (the whole window is mounted on the forms and concrete is poured around them) or left an opening and installed aluminum sliders directly, screwing the frames into the foundation with concrete screws. It's just a matter of cosmetics.

The company that installed my glass block just took a crow bar to the old frames and they came right out. What kind of windows are you going to install? For what they charged me to install the glass block, was probly less then what it would have cost me to do it myself.

You could use three anchors in each side no problem. Just pre-drill an anchor hole in each corner & one in the center. Make sure you put the anchor holes in a place where it won't impede the operation of the window. You may want to get an insert window off the shelf at a local DIY store that's already drilled and ready to go. This would save some time and make things easier for you. Before you pre-drill your holes, always shim behind each screw hole so there's support behind the anchor. If you don't shim the anchor will bow the frame or possibly pull through the material. Having eight anchors would be real overkill. Another important thing for you to do is get the right Tapcon screw length. My rule of thumb when drilling into block walls is no longer than 1" over the length I'm anchoring. Meaning if I have 2-1/2" from the inside of the window where the anchor seats to the block, I use a 3-1/2" screw (#10 or 3/16" shank). This gives you the best thread area to grasp the block wall. If you go much longer the threaded area on Tapcon screws will go past the area it needs to grasp to. Tapcon doesn't thread the entire screw from end to end. They usually only thread the end of the screw and it will go past the thin wall of the concrete block when tightening. That can cause some frustration for the day, believe me. Hopefully your new window opening will be about 3/4" larger in width & height than the window. This allows a 3/8" gap on all four sides for shimming and insulation. Ounce you have the window anchored in place use a low-expansion POLYURETHANE foam to insulate around the window. The "Great Stuff" low-expansion foam in the BLUE can is the best. Don't use the RED can, it will over expand and possibly damage the window. Do not use the DOW low-expansion foam (the white stuff that cleans up with soap & water). It will absorb water like a sponge after it sets up. Apply the foam around the center point behind the window in a 1/2" - 3/4" bead. Let the foam expand and dry before you try and cut it off or push it back. I usually take a utility knife and cut off anything protruding past the window. Ounce the urethane foam drys it also acts as an adhesive. Theoretically you could remove the anchoring screws and never be able to push the window out. I've tried it and it's the truth. I just can't see pulling out good anchors if I don't have to. Your now ready to caulk the gap around both sides of the window. I use a polyurethane caulk called QUAD around my windows (Vulkem will also work). Just try and keep it off your hands and cloths. It's nasty stuff! Also keep the dogs wagging tail away from the stuff or you'll be cutting some fur away. It's a good quality material that will move with the frame if it has to. It's also paint able if need be. You can use a silicone if it's in an area that doesn't require paint. Don't use any kind of Latex caulk because it eventually breaks down and washes away. Construction adhesive would really be non-functional in this situation. Stick with caulk, it's easier to use and stays flexible.