Best 18-Inch Gas Fireplace Log Sets for Different Fireplace Types
If you are searching for an 18-inch gas fireplace insert, note that the products below are gas log sets, not complete inserts. They are sized for compatible fireplaces or fireboxes. The Duluth Forge vent-free sets are best for buyers seeking heat without an open flue, while HearthSense and Duluth Forge vented sets are options for fireplaces with a working chimney. Confirm fuel type and firebox dimensions before choosing.
| Product | Fuel and setup | Best suited for |
|---|---|---|
| Duluth Forge Stacked Oak, LP | Liquid propane, vent-free | LP households wanting remote control |
| Duluth Forge Stacked Oak, NG | Natural gas, vent-free | Natural-gas homes wanting remote control |
| HearthSense Mountain Oak | Natural gas, vented | Higher stated heat output |
| HearthSense Colorado Split Wood | Natural gas, vented | Multiple rows of flames |
| Duluth Forge Heartland Oak | Natural gas, vented | Vented setup with nine logs |
Duluth Forge Stacked Oak LP Log Set
Best for: Buyers whose fireplace uses liquid propane and who want a vent-free log set with remote control. This model produces 30,000 BTU and is listed to heat spaces up to 1,100 square feet. Its seven hand-painted ceramic logs have a stacked red oak design with charring and texture.
Choose this set if LP is the correct fuel and avoiding venting is important. The listed 99.9% vent-free efficiency and remote control distinguish it from the vented match-light options below. It is not a complete fireplace insert, so the existing fireplace or firebox must be suitable for the set. Avoid it if your home uses natural gas.
Duluth Forge Stacked Oak Natural Gas Set
Best for: Natural-gas households looking for a vent-free set with remote control. Like the LP version, it is rated at 30,000 BTU, lists coverage up to 1,100 square feet, and includes seven hand-painted ceramic logs made from real wood molds.
This is the better match than the LP model when the available fuel is natural gas. Its stated vent-free design means it does not require an open flue during operation, unlike the vented models in this list. Confirm that vent-free gas appliances are permitted in your location and appropriate for your home before buying.
HearthSense Mountain Oak Vented Set
Best for: Buyers with a masonry fireplace or vented firebox who want a higher stated heat output. This natural-gas set produces 45,000 BTU and is listed to heat up to 1,650 square feet. It includes seven hand-painted refractory ceramic logs, an iron grate, U-burner chassis, embers, vermiculite, and hardware.
The listed minimum firebox dimensions are 18 inches high, 24 inches wide at the front, 18 inches wide at the rear, and 15 inches deep. The flue must stay open during use. Choose a vent-free model instead if you cannot maintain an open, functioning chimney flue.
HearthSense Colorado Split Wood Set
Best for: Natural-gas fireplace owners who prefer a split-wood look and multiple rows of flames. The 45,000-BTU set is listed for spaces up to 1,650 square feet. Its package includes seven hand-painted refractory ceramic logs, an iron grate, a U-burner chassis, and a bag of embers.
The U-burner is described as creating multiple rows of flames. This is a vented set: it requires a masonry fireplace or vented firebox and a fully functional chimney with the flue open while operating. Do not choose it for a fireplace that cannot meet those venting requirements.
Duluth Forge Heartland Oak Vented Set
Best for: Buyers seeking an 18-inch natural-gas vented set with a traditional oak appearance. It produces 45,000 BTU and is listed to heat up to 1,650 square feet. The package includes nine hand-painted refractory ceramic logs, an iron grate, U-burner chassis, and embers.
Its multiple-row flame design and nine-log arrangement make it a distinct alternative to the seven-log HearthSense sets. The trade-off is the same venting requirement: the fireplace needs a functional chimney, and the flue must remain open during operation. It is not a vent-free option.
Buying Guide: How To Choose An 18-Inch Gas Log Set
Do you need an insert or a log set?
A gas log set places artificial logs and a burner in a compatible existing fireplace or firebox. A fireplace insert is a separate appliance installed into a fireplace opening. These five products are log sets, so they may not meet a request for a complete insert. Check the product type and your installation needs before ordering.
Which fuel does your home use?
Match the set to the available fuel. The Duluth Forge models above include separate LP and natural-gas versions. The HearthSense and Heartland Oak options listed here use natural gas. Do not assume a natural-gas model can run on propane, or the reverse.
Should you choose vent-free or vented?
Vent-free models do not require an open flue during use, according to their listed features. Vented models require a suitable fireplace and an open, functional chimney flue. Installation rules and local requirements can vary, so verify them before selecting a vent type.
How should you compare heat output and fit?
Compare listed BTU output and coverage as product specifications, not a guarantee that a unit will heat your whole home. Measure the firebox and check its shape and minimum dimensions against the product requirements. An 18-inch label alone does not establish that a set will fit.
Frequently Asked Questions
Are these 18-inch fireplace inserts?
No. The products covered here are gas log sets intended for compatible existing fireplaces or fireboxes.
Can a vented gas log set run with the damper closed?
No. The listed vented models require the flue to remain open during operation.
Which option uses liquid propane?
The Duluth Forge Stacked Oak LP model is the LP option among the five featured products.
Do all five sets include remote controls?
No. The two featured Duluth Forge vent-free stacked oak models list remote control. The vented sets are described as match-light models or include match-light operation.
What should I verify before buying?
Confirm the correct fuel, venting type, firebox dimensions, local requirements, and whether you need a log set or a complete insert.