Replacing a broken Window Glass (IGU)

So during my older daughter’s recent birthday party the girls managed to crack the glass of the window in the basement and thus started the research to get it fixed. Quickly learnt that big box stores like Home Depot, Lowes do not do repairs or glass replacement but would actually put in a whole new unit. I just needed the glass and wanted to keep everything else as-is. Also learnt about single pane, double pane, Insulated Glass Unit (IGU) and different types of glass/windows used in a typical home.

My wife did call a few local contractors and the average repair cost was around $200 – $300. Online research also did not yield results immediately on how to go about replacing the glass, so research time and to find a place locally which can actually sell me the glass that I want took forever to find.

So after a lot of googling around what I needed was a double pane glass, also called as IGU. An insulating glass unit commonly consists of two (sometimes more) panes of glass separated by a spacer material and sealed together at the edge. The insulating airspace is filled with air or a noble gas, such as argon or krypton inside. Each glass pane has two surfaces, so typical double-paned IGUs have four surfaces.


Broken window/glass shown below.

The white frame which is vinyl which holds the glass is called a sash, don’t ask me why! So found a good deal of videos on youtube which show how to remove the sash from the main window frame.

So first open the window about 6″ – 8″ up and then slide the 2 locks at the top of the sash in and pull the top part of sash in towards you. Next rotate/twist the window flat parallel to the ground and then dislodge it from the balance groves at the bottom of the sash. This step was fairly easy and straightforward.

Next used a rubber mallet and chisel to remove the vinyl strips or bead which hold the glass in the sash.


I had to search a lot to find a place which would provide the IGU for my custom measurements. Did not find anything local. Found 2 sites online, (located in Washington state) and

But before ordering the glass I needed to understand how to remove this current glass from the sash frame? I searched high and low but did not find anything. I also saw a couple of videos on youtube where-in people had actually smashed the old glass out, instead of removing it out methodically. I did not want to smash it out. I had almost given up and had made up my mind to get a professional contractor come and do the work, when I had an eureka moment!

Based on all the videos and material that I had gone through I decided to run a putty knife between the outside part of the vinyl sash and the window. Essentially that side of the glass is held on to the frame by silicone sealant or a double sided sealing tape.

That did it. The light brown colored rectangular piece in the 3rd picture above are spacers used on the edges, 2 on each side, so 8 in total, I re-used these. Some sort of vinyl material I suppose, couldn’t figure out what they were made up off, or where to buy new ones from.


Sash and glass separated as shown above.

I used to order mine in. So in order to place an order you need to know the following.

  1. Type of glass – IGU in this case
  2. Shade – rectangle (almost square in my case)
  3. Dimensions of the glass 30″ w x 30 1/4″ h
  4. Thickness of the glass unit – 3/4″ in my case
  5. Space bar color – I got aluminium one, other choices were champaign and dark bronze color
  6. Glass Tint – clear, there are a lot of choices here
  7. Grid (in-between the 2 glasses) – 5/8″ white 3 x 2 pattern

So glass costed me $91.33 + $48.00 – FedEx Ground = $139.33. It took around 10 odd days to arrive.


Also got a double-sided window glazing tape from amazon for $15.

Removed the old silicone, double-sided glazing tape from the sash, used a blow dryer, heat does the trick.


Did a dry fit first of the new glass in the frame to get an idea on how to place the brown spacers. Removed the glass and then my wife helped in applying the new double-sided window glaze tape around the perimeter. Yes, I know I have a lot, didn’t come in any smaller size/length.


There is a small metal capillary tube which should end up at the top side of the window. It needs to be cut off if the window cannot make it in the sash and sealed using silicone sealant. So I did purchase a small tube of silicone from Home Depot.  Used packaging tape to hold it in place when I applied silicone but that did not help much, so eventually I took the tape off. I did not have to cut the tube, just sealed it with silicone. I could have also used the silicone instead of the double glazed tape I think and saved a little.

This capillary tube is used to fill in gas like argon etc in high altitude places but it my case its just air filled.

Placed the new glass in the vinyl sash frame on the double glaze tape, made sure the spacers aligned properly and then put the vinyl strips back on. Putting these white strips back on was a pain, but I used my clamps and they were perfect for this job.


Finished window sash.


Hung the sash back on the window frame and that’s it!!



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