Measuring for replacement windows.

I am going to replace the windows in my sons room. What looks like the frame also looks like it could be part of the window. I have been looking at double hung, 2 window replacement units.



I am guessing that the 1x4 trim around the window should stay but the middle 2 1x4's should be removed. They form a T at the top and bottom that indicates that nothing that I can see in the first picture should stay but it must, right?

I think that I should measure from the inside of the 1x4 on the right the inside of the 1x4 on the left and from the insides of the 1x4 on the top to the sill.





I would like to get a second, third, etc opinion before ordering the windows only to find out I have the wrong ones. I also understand that there should be a little space left for expansion on all sides, but how much?

Any pointers or help is appreciated.

Thanks,

Steven E. Johnson

 

Always have a window dealer rep come out and measure for replacement windows.
If you screw up doing any measuring and guessing, it's YOUR problem.
If they screw up, it's THEIR problem, and they have to correct it at their expense.
And they should be able to answer all of your questions about your specific needs, and give you installation information.
You need beveled shims around the window frames to make them plumb and level, and although they say that it's unnecessary, I always caulk the flanges and flashing.
Good Luck!
Mike