When they put a gas insert in they line the old flu...

@arcy_gw yes our understanding is that gas inserts have their own liners, so we dont need to fix the cracks on the current flue. This is our understanding but we could be wrong.....

Gas insert would be my choice. We replaced our gas logs with one last year.

@jrb451 hi! can you elaborate on why you replaced your logs with inserts? Thank you

A couple of winters ago we had an unusually cold snap (for us). The temperature got down as low as 0 one night. We used the gas logs during this period as supplemental heat, burning them several hours each day. We noticed that most of our houseplants, and we have many, started dropping leaves and looking pretty pitiful. We had never experienced this before and attributed it to the gas logs. Our thinking was that if it did this to the plants, what was it doing to us?

I never noticed gas heat drying out the air that much. We have a wood burning insert in our other fireplace and it will but it wasn’t in use during this time period. FWIW, we have a GSHP for our central HVAC system.

In my experience, gas logs look better and gas inserts kick out a lot more heat. If you really need it for heat then gas insert. If you want a nice looking fire gas logs.

My parents had a gas log for 20 years and my mom had a ridiculous number of plants. Gas logs didn't affect them so ymmv.

They also had a gas fireplace with a blower in the basement. That was nice to heat the basement but it could only be on for a short period of time before it became unbearable.

I have a gas insert now without a blower. It's not as hot as with the blower so we can have it on longer but it still doesn't look very nice. Personally I prefer a gas log. But we live in MN and have good central heat so we don't need it for heat.

I don't have experience with gas log - other than to say I think they give off less heat. But, we replaced our gas insert fireplace a few months ago and are very happy with the decision. We already had one, but it was small and had lots of iron decor around it so this was a nice upgrade. Got one with a blower (brand name Regency) which actually gives off some heat to the room. Use it almost every night.

In NJ too.

The HUGE drawback to a conventional fireplace is that they draw their combustion from the house. You may be heating one area but other areas are being cooled/chilled from the outside air being sucked through leaks.

Go with a direct vent sealed combustion gas insert. A direct vent gas appliance is a closed combustion system, sealed off from the living environment of your home. Outside air flows though a sealed pipe, directly to the burner. Exhaust gas flows back outdoors through a separate sealed pipe. There are two types of Direct Vent systems; Coaxial and Colinear. These types of units can really heat a house! So good are they that I have had to modify my return air ductwork to pull the room heat out (to keep that room tolerable) and get it back to the furnace blower to circulate around the house.

I have two such Jotul units, a gas fireplace (Accadia GZ550) and a free-standing gas stove (Sebago GF400). Caution: a quality product will cost substantial $$. I've included the Jotul inserts available here:

https://www.jotul.com/products/gas-inserts