How do I hold an IGU into a wood storm window sash?

I am making some insulated glass storm windows. I'm ready to insert the 3/4" thick IGU into the wood frame but not sure the best way to hold it in place. I've read you should not use the traditional white glazing compound as the oils in it interfere with the IGU's seal.

My plan is to first put some thin, flat glazing foam tape which will sit between the glass and the wood frame. The tape I'm using is 1/8" thick and 3/8" wide.

After I put the insulated glass against this tape, how do I hold the glass unit in place and finish it off?

Is it ok to use the little metal push points with an insulated glass unit (IGU)? If I use push points, what type of glazing compound or caulking do I then use to seal the edges?

Here is a photo of the IGU sitting in the wood frame (but nothing yet holding the glass in place) and one of just the wood frame.

http://img80.imageshack.us/img80/5130/dscn0560e.jpg

http://img706.imageshack.us/img706/7060/dscn0561.jpg

I made the frames out of 2x3 cedar and used a dado blade to remove a big section to hold the glass. I used the dado blade again to make the lap joints at each corner and then dowel jointed them. I'll prime and paint them before inserting the glass. (Thanks to Oberon for helping me figure out the best glass to use).

Thanks!

 

Do not use glazing points. The glazing tape with adhesive on both sides will hold the glass against the rabbet. You must use rubber setting blocks (1/8" X 3/4") at the bottom of the sash for the unit to sit on and also. I can't determine how much depth is left for using a wood molding to hold the unit which is what you should use and it should be sealed against the glass with silicone or a latex caulk. By the way, nice job on the frames.

 

I made the frames with a 1/4" gap to allow for push-points and glazing putty. I can use silicone caulking instead of the glazing putty but what's wrong with using the push points with an insulated glass unit? I've unfortunately built the frame to use push points so not quite sure how I'd hold the glass in without them.

Thanks for the compliment on my frames!

 

Not all glazing compounds are oil based,there are latex products.Perhaps they would have less impact on your seals than oil based products.

If you use silicone and one of these ever gets broken you'll have a tough time repairing it as silicone is difficult to remove.

This may not be why points were not recommended but I'd be concerned expansion and contraction of the glass against the points would crack the glass.

 

We never used glazing points when installing IGU's probably because it was not that secure and could put stress at those points. I guess it's too late for a molding but being good at wood working you should be able to make a molding. The idea I have is an L with the short part of the L's dimensions that would fit the width and depth of the rabbet and the long part of the L is the width of the rabbet plus about 3/4" overlap onto the frame to nail through. It's hard to explain. I wish I could attach a drawing.