Glazing compound or caulk?

Many times panes of glass in single pane, double hung wood windows have be repaired using caulk instead of the glazing compound traditionally used.

Defect in and of itself? Or is caulk an acceptable modern substitute?

I would have no concerns with using any good quality exterior grade caulk as it is meant to remain flexible and waterproof for an extended period. I was taught to reglaze /seal windows by an old time painter and the linseed oil based putty is still available in most paint depts of the big box stores. Caulk would of course be much more difficult to get the traditional 45 degree angle of the putty so it would not have the same appearance that putty gives. When chosing to caulk colour might be a concern as putty was a paintible surface and some caulks are not.

I disagree Bruce.
Nobody uses caulk for a good reason,it does not stick to dissimilar or porous wood surfaces very well.

The caulk may just detach.

I have worked with caulk and glazing compound many times replacing panes and glazing compound can be worked then reworked and cleans off the glass easily while caulk makes a mess of things .

Bear in mind that the points are what actually hold in the glass.(careful also that caulk is paintable plus is it silicon,urethane,etc).

Bob, depends entirely on the type of caulk There are hundreds of types that stick to everything dissimilar from high temp caulk that is used on mortar to metal joints to windshield caulk that attaches glass to steel and caulk that is used to both fasten and seal wood to many other materials. There are many silicone types that adhere to both glass and wood for an effective seal as well as paintable silicones on the market. Yes you are right, paintable is always a requirement if the caulk is not the right colour to begin with. You are also correct in that the points hold in the glazing traditionally and I did reuse them sometimes but I have seldom reused the glazing putty. The painter that taught me to do the reglazing and puttying considered it not worth his while to add oil and spend time working the putty soft again. He also pointed out to me that if it had been painted over the flakes left prevented a good smooth bevel every time ad so wasted his time redoing it. Of course that was when the windows were often being reglazed rather than being updated with newer type windows and both painters and glazers did them regularly.

One of each here;


So caulk isn’t a defect, as long as it’s sealed and angled to shed water.

I’m still using compound on mine next time.

Glazing compound have evolved.
Latex. Oil based.
They both are suited for there individual purposes. Interior and exterior use.
Oil based. Exterior and interior but odor related.
Latex for interior due to its odor is lass apparent but liquid in nature as compared to oil based. Hard to work with as compared to oil based.

They are the only type to be used for glazing a wooden window frame.
It allows the reapplication if failure is an issue and the glassing has to be reintroduced.

Caulk on the other hand is not as easy to work with to apply the spastic bead, and does not have the same bonding properties.
The cleaning of the pain after it has been caulked, depending upon the caulks chemical makeup my be difficult or imposable to remove and may break the pain and make the window unrepairable.