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tonyc56
Silicone versus Glazing for sealing replacement glass

All,

Could someone tell me if silicone can be use in place of glazing for seal glass replacement.

I've read mixed opinions some say yes others say no...Whose right?

dj1
Re: Silicone versus Glazing for sealing replacement glass

It's your call.

For older metal windows (not aluminium) or wood frame windows I like to use DAP glazing material. It's easy to bevel and to apply, cause it's not as messy as silicone. I use silicone for smaller, narrower applications, where less material is needed.

A. Spruce
Re: Silicone versus Glazing for sealing replacement glass

Like DJ said, it's more about the application and your preference. In older metal frames and wood windows, glazing is the best because you set the window into the glazing and then apply a second bead over the top. It takes a bit to get the hang of it, but the great thing is if you mess it up, you simply scr-ape it out and reuse it. You can't do that with silicone, nor in this case is silicone going to be workable due to the quantity being used and tooled.

On aluminum and vinyl windows bedding the glass into silicone (beutyl caulk is better ) is acceptable/preferable because there is an exterior rubber/metal trim the goes on to cover the perimeter of the glass. Run a bead of silicone around the frame, press the glass into the frame with an even reveal around its entire perimeter (use shims to hold the bottom space while the silicone dries ). Let the silicone fully cure before removing any of the oozed out material from the inside of the window. When it's cured, you simply run a utility knife along the frame and the excess silicone will peel right off. If you try to play with it while wet, you'll have a serious mess on your hands. Beutyl caulk is better because it's more stable than silicone. You'll apply and handle it similarly as silicone.

Re: Silicone versus Glazing for sealing replacement glass

Silicone can't be painted.

ordjen
Re: Silicone versus Glazing for sealing replacement glass

There is a reason glazing compound has been used for a hundred years largely unchanged. If it ain't broke, don't fix it!

The other posters have stated good reasons: compound is easy to use, forgiving, can be painted, and does not leave a hard to clean up residue.

Most later day alternate glazing systems don't use silicone, but a butyl rubber type compound. Silicone does have long lasting attributes, but the difficulty of application, and eventually its removal, overweight those attributes, especially for the average homeowner.

A. Spruce
Re: Silicone versus Glazing for sealing replacement glass
ordjen wrote:

Silicone does have long lasting attributes, but the difficulty of application, and eventually its removal, overweight those attributes, especially for the average homeowner.

All reason that I despise silicone caulks and lobby for the use of alternatives that are either better products, easier to use, and most certainly easier to deal with when it fails.

Sombreuil_mongrel
Re: Silicone versus Glazing for sealing replacement glass

If we are talking about single panes in old-style wood sash, then use glazing compound not caulk. If we are talking about insulated glass in newer doors and windows, then use a butyl caulk or a flexible polyurethane sealant such as Lexel.
Casey

tonyc56
Re: Silicone versus Glazing for sealing replacement glass

Hi Sombreuil_mongrel

why glazing for single panes in old-style wood sash and caulking for insulated glass.

Thx

Sombreuil_mongrel
Re: Silicone versus Glazing for sealing replacement glass

The newer glazing systems are done with sealants not old-time oil+chalk compound.
Does the glass go in from inside (new systems) or outside? If from outside, use putty, otherwise use sealant.
If there was a sealant, use a sealant. If it's 50+ year old wood sash where there was compound, use compound.
General rule: put back what was there, it was there with good reason.
Casey

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