Glass Doors for See Thru Fireplaces
"Will glass doors prevent my double sided fireplace from smoking"
"Can I seal off one side with a piece of glass"
"What about Ceramic Glass?"
This article will answer these questions in detail
By: Greg Tillotson - Upated 10/8/2019
If you have a double sided fireplace that is open to two rooms, you probably have a problem with smoke. Truth is, most see through fireplaces smoke because of drafts in the home that push air through the fireplace from one room to the other, bringing with it a puff of smoke. Some see-thru fireplaces are so sensitive that just walking past them can pull a puff of smoke into the room. For this reason many people (maybe even yourself) have found this page in hopes of a solution...so here it is.
"The Solution: Add glass doors to both sides of your fireplace and burn it with the doors closed!"
Yes, if you add glass doors to both sides of your fireplace and burn a fire with the doors closed, you can minimize your smoke problem. Fireplace doors made for this purpose will have a draft assembly at the bottom that allows air to feed the fire evenly from both sides causing the smoke to go straight up the flue. The room air rushing towards the fireplace keeps the glass relatively cool and the flames away from the glass. However, most glass doors are not designed to be burned with the doors closed, which is one of the main reasons we sell Fireplace Doors made by Design Specialties, because they are.
"Can I close the doors on one side or just seal off one side with a solid piece of glass?"
If you attempt to burn the fire with one door open and one door closed, or you are considering sealing off one side with a single fixed piece of glass, you will quickly discover that the flames will blow towards the closed side just like they would on a typical single sided fireplace. So essentially the closed door or sealed off side acts like the back of the fireplace where the most intense heat builds up. Even the best fireplace doors that are designed to be burned with the doors closed cannot handle prolonged exposure to direct flames and the heat build-up will eventually shatter the glass.
"Can I use ceramic glass to seal off one side?"
Some people online suggest you seal off one side of your fireplace with ceramic glass. The 1/4" thick tempered glass used high end fireplace doors can handle up to 400 degrees or so, whereas ceramic glass may able to handle 1200-1400 degrees. That sounds like it will work, but in reality, it may not be so practical due to the cost. For example, the upgrade cost for a fireplace door from 1/4" tempered glass to ceramic glass is a whopping $1200 and there is NO warranty. We spoke to the engineers at Design Specialties and they basically said, "yes, we can do that, but we are not going to be held liable if that piece of glass breaks...it's just too expensive and too risky to provide a warranty on ceramic glass". With that said, I reiterate that Design Specialties has a lifetime warranty on their tempered glass, but no warranty on the very expensive ceramic glass. It's cheaper to buy doors for both sides of your fireplace than it is to buy a single door with ceramic glass. So we believe that the cost is not worth the risk, but leave it up to you as to whether you would consider it a viable solution.
Gas Fires: It is important to know that you cannot burn gas logs or other gas fires with your fireplace doors closed, they must be fully open. This is just a rule with gas logs since the controls are not made to handle the heat build up with doors closed and the air to fuel mixture is incorrect, which will cause the logs to soot up and produce too much carbon and carbon dioxide (toxic gas). This rule is for gas logs that are made to be installed in a wood burning fireplace, this does not apply to certain gas fireplaces that cannot ever burn wood, they are special appliance that draft completely differently and are made for such purposes.
If you want to add glass doors to your fireplace, please Email Pictures Of Your Fireplace to us so we can make some recommendations.