Hi, I am in a similar position. One thing that you would probably want to find out is what your walls are made out of. In my house, the structural element of the walls is cement block, so my house is considered a masonry house. Other people with brick exteriors have walls made of 2x4 studs. This will affect how the old windows are removed and how to install new ones. I would take out the entire aluminum window, frame and all, because aluminum is a horrible insulator. I recently replaced one of my windows and it took me about 3 days of work. I purchased an angle grinder with a cut off blade to cut through the aluminum window all around the edge. There is a flange that goes behind the brick on the outside and another one that goes behind the plaster on the inside. Additionally there were metal attachments that were mortared to the cement block and were holding the window frame in place. These attachments were not visible or accessible without cutting into the frame. I had previously tried to remove the frame by taking out all of the screws that I could see, but it would not budge at all, which is why I decided to cut into the window frame itself. Removal took about half a day. This is the first window I ever replaced in my life, so I was taking it slow and trying to think about every action I took, so that ate up a lot of time. I decided to attach a wood frame to the rough window opening before putting in the new window, so that took a good bit of extra time to cut, shave, paint and caulk. It was satisfying, but my wife says it took too much time and would like to hire someone to do all the rest of the windows. Do you live in a climate with cold winters? We have cold winters, and the aluminum windows just conduct the cold right into the house. You might want to have some contractors give you a quote, and ask them a lot of questions about exactly how they would tackle the job, they can be a wealth of information, and you may just decide to hire them as well.

nah, we only see below freezing temps at night. most of the time during the winter the high for the day is in teh 40's and lows in the mid 30's. the existing windows get VERY cold though. and during the summer our temps are around or over 100 for most of the time, with lows int eh 70's to occasionally low 80's. even though there is no air leaks around them that i can detect, you fell the heat/cold radiate from them.

our house is a brick facade over 2x4 and some walls 2x6. it loks like the windows were installed prior to the brickwork, so i hope they will come out relatively easily, but with my luck it will be soemthign akin to what you went thru!

Sounds like you are going to try it yourself. Thats the spirit! You just want to make sure you take good measurements to order your windows. Measure multiple times at different points, and then you should probably subtract a little bit from that (1/4 or 1/2 inch). When I ordered my custom sized window, I thought the dealer was subtracting 1/2 inch from my measurements, but there must have been a miscommunication, because the window I got was the exact measurements that I gave him, which, of course, almost fit my opening, but was a smidge too large. Since I had put wood inside the opening, I was able to shave down one of the wood frame sides and got it to fit. Anyway, the measurements are pretty important to get right. I actually removed the window and then took my measurements, and then ordered the window, just to make sure that my measurements were as good as possible. I would definitely recommend getting custom sized windows. I assume you are getting vinyl windows. I would also recommend getting a higher quality window, such as Simonton or Certainteed. Good luck.