Bill ,
That plastic incasing you are reffering to is called a sash ... actually depending on the window and 9.9 times out of ten it isnt solid .. The glass is two layers with a aluminum bead in between them sealed with a non-hardening epoxy then gas filled to prevent fogging , the outside of the sash has whats called a fleagle ( not 100% sure on the spelling but that is what the word sounds like
) ... What you do is use your 5 in 1 to pry the fleagle out of its locking channel on the sash frame ... If its really old or cold you might find its easier to heat / warm the fleagle up with a heat gun to make it easier there will be adhesive back there in alot of cases... Once the fleagle is removed you warm up the adhesive that is bonding the glass and the sash frame and the inside man runs his putty blade in between the two surfaces thus popping out the glass .... do the same for top and bottom sashes .
For anyone else that might care though , next you use your pry bar and hammer ( If Aluminum or Steel Framed , its alot easier if its the newer vinyl windows ) to bend inward the lips of the frame that the sahes are in this will allow to remove the sashes from the main window frame ... Dont worry about being gentle with it
.. Once you are down to no windows and the empty frame in the hole , this is where the pry bar and 1x peice of would come into play , since new construction windows and usually nailed into place you start prying (from the inside) in the middle of the longest length of the frame ... from there its pretty explanitory as the fram has already started to collapse inward and is just a matter of breaking the rest of the original flange loose ...
No mind you there have been alot of different manufacturers out there over the years so i have ran into many a odd ball window that took different approaches but with the same result , window goes bye bye ...
Anyone needs any help with this area of home maintenace , I would be more then happy to walk you through it on the phone , just ask ...
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