The best gas line for an outdoor fireplace is one that matches the appliance’s fuel, connection size, required flow, and installation layout. For a short connection, the Stanbroil 24-inch line offers 3/8-inch fittings, while the Midwest Hearth line provides a 1/2-inch inside diameter. The Dreffco 18-inch line is another fire-pit-oriented option; the Stanbroil 12-inch model suits shorter runs. The 70-foot CSST kit is a different type of product for longer routing, so confirm its suitability with a qualified installer before choosing it.
| Product | Best For | Key Detail |
|---|---|---|
| Stanbroil 24-Inch | Short connections using listed 3/8-inch line dimensions | Brass fittings, including a 90-degree fitting |
| Midwest Hearth 24-Inch | Fire features needing a 1/2-inch ID line | Whistle-free corrugation; 1/2-inch MIP to FIP |
| Stanbroil 12-Inch | Compact connections | Short stainless steel flex line with brass fittings |
| Dreffco 18-Inch | NG or LP fire-pit connections | 1/2-inch flexible stainless steel line |
| Grehitk 70-Foot CSST | Longer gas-line routing projects | 3/4-inch CSST with two male adapters |
Stanbroil 24-Inch Flexible Gas Line Kit
Best for: Buyers who need a 24-inch connector with the listed 3/8-inch outside diameter and 1/4-inch inside diameter. The product is described for a flexible gas connection and includes brass fittings, making it a candidate for an outdoor fireplace or fire-pit setup only when its specifications match the appliance and installation plan.
The corrugated stainless steel pipe has a black coating, and the listing describes it as durable and resistant to high temperatures. Its ends include 3/8-inch male flare by 1/2-inch male NPT and 3/8-inch male flare by 1/2-inch female NPT fittings. A brass 90-degree fitting is included for connection convenience.
Choose this if those exact end connections and the 24-inch length suit the installation. Avoid choosing by length alone: the 3/8-inch outside diameter and 1/4-inch inside diameter differ from the 1/2-inch-ID options below. Verify fitting type and required flow before purchase.
Midwest Hearth 24-Inch Whistle-Free Gas Line
Best for: Buyers whose fire feature calls for a 1/2-inch inside-diameter flex line and 1/2-inch MIP-to-FIP fittings. The manufacturer describes this line for indoor and outdoor uses, including gas fire pits, gas log sets, fireplaces, and other fire features.
The corrugation pattern is designed to disrupt vibrations associated with whistling. The listed dimensions are 1/2-inch ID by 5/8-inch OD, and the specified ends are 1/2-inch male iron pipe (MIP) to 1/2-inch female iron pipe (FIP). These details make it easier to compare against an appliance’s connection requirements.
Choose this over a smaller-diameter connector when the appliance instructions call for the listed 1/2-inch size and compatible ends. Its limitation is that the provided details do not state a length or flow capacity, so confirm both with the seller and appliance documentation before ordering.
Stanbroil 12-Inch Flexible Gas Line Kit
Best for: A short connection where a 12-inch line and the product’s listed 3/8-inch flare and 1/2-inch NPT ends match the installation. Its compact length can be useful when the appliance and gas supply are close together, without requiring the extra reach of a 24-inch connector.
The kit uses corrugated stainless steel tubing with a black coating. The listed dimensions are 3/8-inch OD by 1/4-inch ID, and the fittings include 3/8-inch male flare by 1/2-inch male NPT and 3/8-inch male flare by 1/2-inch female NPT. A brass 90-degree fitting is included. The listing describes the line as durable, easy to install, and resistant to high temperatures.
Choose this if a shorter run is appropriate and the connection details match the appliance. Its 12-inch length limits reach, and the 1/4-inch ID may not suit every appliance’s flow requirement. Check the appliance specifications rather than assuming that a short connector will work for every fire feature.
Dreffco 18-Inch High-Capacity Gas Flex Line
Best for: Buyers looking for an 18-inch, 1/2-inch flex line described for natural gas or liquid propane fire pits. The product is also described for fireplaces and other gas appliances, but the appliance’s required fuel and connection specifications still need to match.
The line uses corrugated stainless steel tubing with a black finish. Its flexible design is intended to route around corners and tight spaces. The listing also describes it as a non-whistle gas hose designed to help lessen unwanted airflow noise sometimes heard with gas appliances.
Choose this if the 18-inch length and 1/2-inch size fit the planned connection and the manufacturer’s instructions allow the stated fuel. The listing does not specify the end-fitting types or provide a flow-capacity figure in the supplied details. Confirm those points before buying, particularly if the fire feature has a stated minimum line size or flow requirement.
Grehitk 70-Foot CSST Gas Line Kit
Best for: Buyers planning a longer gas-line route who need to compare a 3/4-inch CSST kit with a qualified installer’s design. At 70 feet, this is not a short appliance connector like the other products in this list. The listing states a 0.63-inch inner diameter, 0.79-inch outer diameter, and two male adapter fittings.
The product is described as corrugated stainless steel tubing with a yellow polyethylene jacket. Its listing gives a flow-capacity claim of up to 150,000 BTU per hour. It also says the tubing can be routed around corners and that underground routing requires placement inside a nonmetallic, watertight conduit at least 1/2 inch larger than the tubing’s outer diameter.
Choose this only when a long CSST run is appropriate and the line, adapters, fuel, and installation method are verified for the project. Its length and 3/4-inch size may be excessive or unsuitable for a simple fire-pit connection. The supplied product information also says it should not be buried directly underground without conduit.
Buying Guide: How To Choose A Gas Line For An Outdoor Fireplace
What size gas line does the fire feature require?
Start with the fireplace or fire-pit manufacturer’s installation instructions. Check the required line diameter, connection type, fuel, and any stated flow requirement. A line’s outside diameter is not the same as its inside diameter, and fittings described as NPT, MIP, FIP, or flare are not interchangeable terms.
For comparison, the two Stanbroil products list 3/8-inch OD and 1/4-inch ID tubing, while the Midwest Hearth line lists a 1/2-inch ID and the Dreffco line is identified as 1/2 inch. The Grehitk product is 3/4-inch CSST. These dimensions alone do not establish that a product is right for a particular appliance.
How long should the gas line be?
Measure the connection route and account for the way the line must be positioned. The available products range from 12 to 24 inches for compact connections, with the Dreffco at 18 inches. The Grehitk CSST kit is 70 feet long and is intended for a very different routing scale.
Do not use a longer line simply because it is available. The correct length depends on the installation design and appliance instructions. Avoid stretching, sharply bending, or forcing a connector into position; ask a qualified gas installer to assess routing when the path is unclear.
Does the line need to work with natural gas or propane?
Confirm whether the fire feature is configured for natural gas (NG) or liquid propane (LP). The Dreffco listing specifically describes use with NG or LP fire pits. That wording does not replace checking the appliance’s fuel configuration, pressure requirements, or installation instructions.
Do not assume that a connector suitable for one fuel or appliance automatically suits another. If the fuel source, regulator arrangement, or required fittings are uncertain, consult the appliance manufacturer or a qualified gas professional before selecting a line.
Which fittings should you compare?
Match each end of the connector to the corresponding supply and appliance connections. The Stanbroil kits list a combination of male flare and NPT ends, with different male and female NPT configurations. Midwest Hearth lists 1/2-inch MIP-to-FIP ends. The Dreffco product details provided here do not identify end-fitting types, so those should be confirmed.
Check whether adapters are needed and whether they are appropriate for the intended gas installation. A fitting that appears to be the right diameter may still have the wrong thread type or gender. Do not rely on appearance or product title alone; compare the manufacturer’s specifications.
Is a flexible connector or CSST more appropriate?
A short flexible connector is generally the product category to compare for a nearby appliance connection. CSST is a tubing system for routing gas over a longer path. The 70-foot Grehitk kit includes male adapters, but the information provided does not establish every component or installation detail needed for a particular project.
Longer routes, penetrations, outdoor exposure, and any underground routing can bring additional installation requirements. The Grehitk listing specifically says not to bury the tubing directly without the described conduit protection. Have a qualified professional check applicable local requirements and the full routing plan.
Should whistle-free construction matter?
Whistle-free designs are intended to reduce noise associated with gas flow. Midwest Hearth describes corrugation that disrupts vibration patterns, while Stanbroil and Dreffco describe their options as non-whistle. This feature may matter if gas-flow noise is a concern, but it should not take priority over correct sizing, fuel suitability, fittings, and installation.
What should you verify before installation?
- Read the fire feature’s installation manual and confirm its fuel and connection specifications.
- Compare the line’s inside diameter, length, fitting types, and stated flow information with the project requirements.
- Check the product details for intended indoor or outdoor use and the proposed routing conditions.
- Ask a qualified gas professional to review the installation and applicable local requirements when uncertain.
- Follow the appliance and installer’s instructions for completing and checking the gas connection.
Frequently Asked Questions
Can I use any flexible gas line for an outdoor fireplace?
No. The line must match the appliance’s fuel, size, connection types, flow requirements, and installation instructions. Confirm those details before purchasing.
Is a 1/2-inch gas line better than a 3/8-inch line?
Not automatically. The correct size depends on the appliance and installation. Compare the manufacturer’s specified inside diameter and flow needs rather than choosing by nominal size alone.
What is the difference between NPT and flare fittings?
They are different fitting types. A connector with the right diameter can still be incompatible if its fitting style, thread, or male/female end does not match the connection.
Can the 70-foot CSST line be buried?
The product listing says it should not be buried directly underground without a nonmetallic, watertight conduit meeting the stated size guidance. Confirm the complete installation method with a qualified professional.
Which listed gas line is shortest?
The Stanbroil 12-inch kit is the shortest listed option. It is suitable only when its length, 3/8-inch OD by 1/4-inch ID tubing, and fittings match the specific installation.