Window rebuild question

[Marty Paulus]

OK in reading the thread about the carriage doors it was mentioned to use glazing putty to hold the windows in because the wood strips may fail. This is a section of what a friend is planning for some windows in an old building to replace the ones that are rotting in their frames. My question is will this work as a long term solution? Not only am I concerned about the glass actually staying in (these are second floor windows in a small downtown area) I am concerned about the window actually sealing without a continuous bead of sealant around the glass. He is only planning on short beads of silicone to act a cushions for the glass and is hoping the paint will seal everything. I would hate to see all the work he is putting into this all be for nothing if they are going to be drafty and leak. I have only used glazing putty to repair windows of this style and that was over 25 years ago.

[Rich Engelhardt]

Hello,
Coat the wood with boiled linseed oil to prevent the wood from wicking the oil out of the glazing compound.
Put the pane of glass in place.
Use glazing points to secure the glass.
Use Dap #33 oil glazing compound to glaze the windows.
Prime the glazing with an oil based primer & finish it with any top quality sash paint.

Wood trim strips won't prevent water from getting to the wood underneath and causing rot.

[David G Baker]

The paint may work but with the expansion and contraction of wood I wouldn't count on it. The space between the glass and the exterior brad nailed piece of trim will make a great place for water to sit and like Rich wrote, cause wood rot.
I have several windows that were glazed and painted where the paint is gone along with the glazing material. The glass is sitting on a flat surface where the water has a chance to dry, in you described method there is that pocket for it to just sit there and do its thing.

[Trace Beard]

I wouldn't glaze the windows like that, at least use a continuous bead of silicon. If your friend needs some info point him to Historic HomeWorks, they have a great forum on windows.

http://historichomeworks.com/forum/viewforum.php?f=16&sid=1684f0a1c8c1686db976a2a10ee8180d

[Peter Quinn]

You need a continuous bead of silicone or latex window glazing (which now comes in a handy caulk tube applicator with a square tip for application) in which to 'seat' the glass, or your friend is asking for trouble. You apply a continuous bead along the bottom of the glass rabbit and set the pane into this, then apply the glazing points, then either glaze with putty or applied stops. The window will not seal and will rattle beyond belief in a stiff breeze without this. That technique may work in a cabinet door but is not appropriate for a true exterior glazing application.

Alternatively you can use glazing tape in place of the silicone in this application (available from most good glass shops), again applied to the bottom of the rabbit (the part closest to the interior of the home), or you can use a silicone glazing gaskets available from http://www.conservationtechnology.com/building_glazing.html.

With applied stops the bottom rail must be beveled to shed water away from the glass rabbit BEFORE the stop is applied, and the stop can be designed aesthetically to accommodate this detail accordingly. Building a shelf to hold water behind an applied stop is about the poorest window construction I can think of and should be avoided. Also encourage your friend to learn and observe any applicable codes regarding the use of tempered and or low E glass for replacement purposes. Not sure where your at but here in the Northeast these things are generally regulated, in in my state you need a license to charge money for glazing windows, somewhat for tax purposes but also for building safety and integrity.