Short answer: neither brand wins every job. AllFuel HST suits 6" or 8" installs that want all-stainless pipe and a through-the-wall kit. DuraVent DuraTech suits projects that need more sizes, more parts, or a trained installer.
Why This Comparison Matters
A Class A chimney carries flue gases from a stove that can run for hours. A weak choice here is not a cosmetic mistake.
We compared the two systems using manufacturer documents, retailer listings and code references. We did not lab-test anything. Where a claim is marketing, we say so.
What Both Chimney Systems Share
Before the differences, here is the common ground. Both are double-wall, insulated, all-fuel systems.
- Listed to UL 103 HT for 5"–8" DuraTech and for AllFuel HST's 6" and 8" sizes (DuraVent; AllFuel HST brochure).
- Twist-lock joints that need no tools.
- 2 inches of clearance to combustibles.
- A "limited lifetime" warranty, with fine print.
What "UL 103 HT" Actually Tests
UL 103 HT is a high-temperature chimney standard. It covers appliances listed for use with 2100°F chimney systems.
According to a retailer listing for AllFuel HST, the test includes a one-hour burn at 1400°F. It also adds three ten-minute burns at 2100°F.
AllFuel HST: What You Actually Get
AllFuel HST makes 6" and 8" Class A pipe, per its own brochure. It is a narrow lineup, but a focused one.
- Inner and outer walls of 0.019" 304 stainless steel.
- Ceramic fiber blanket insulation, listed as 1.18" thick by one retailer.
- A locking band included with each pipe length.
- A base wall support kit rated for up to 52 feet of chimney (ComfortBilt).
The brand also claims its walls are thicker than competitors'. Listings say 17% in some places and 25% in others. Treat that as a sales line, not a measurement.
One practical limit matters. A Home Depot listing says its attic insulation shield does not fit other brands' Class A pipe.
DuraVent DuraTech: What You Actually Get
DuraTech is DuraVent's all-fuel line. The 5"–8" range carries a combined UL and ULC listing, according to DuraVent's product page.
- Ceramic refractory blanket insulation between the walls.
- Listed to UL 103 HT and ULC S604 for 5"–8" sizes.
- Larger 10"–24" sizes, listed to UL 103 with a 1700°F ten-minute test (DuraVent catalog).
- A reduced-clearance square ceiling support box, for 6" DuraTech only.
- A stainless or galvalume outer casing, depending on the part.
Here is the catch. A retailer listing says DuraVent's warranty applies only when a trained professional installs the product. Read that before you grab a ladder.
AllFuel HST vs DuraVent: Side-by-Side
| Feature | AllFuel HST | DuraVent DuraTech |
|---|---|---|
| Sizes | 6" and 8" | 5"–8" (HT), 10"–24" (UL 103) |
| Listing | UL 103 HT | UL 103 HT and ULC S604 (5"–8") |
| Wall material | 304 stainless, both walls | Stainless inner; stainless or galvalume outer |
| Insulation | Ceramic fiber blanket | Ceramic thermal blanket, 1" |
| Clearance | 2" | 2" |
| Warranty | Limited lifetime | Limited lifetime; installer condition noted by retailers |
| Mixing brands | Listing says not compatible | Use DuraVent parts throughout |
The Rules That Matter More Than the Logo
Your brand choice sits below your local code. Chimney height, clearances and listing rules apply to both systems.
- The chimney must rise at least 3 feet above where it exits the roof.
- It must also stand 2 feet higher than anything within 10 feet.
- Factory-built chimneys must be listed and installed per manufacturer instructions.
The roofing trade body NRCA's magazine confirms the 3-2-10 height rule for IRC and NFPA 211. The California Mechanical Code states the listing and instruction rule.
NFPA 211 is a model code, so your city may enforce a different edition. Ask your local building department first.
Who Should Pick Which System
Match the product to the job, not the other way round. These profiles describe the fit, based on the specs above.
- AllFuel HST fits you if your stove uses a 6" or 8" flue and you want a through-the-wall kit.
- AllFuel HST fits you if you prefer stainless on both walls.
- DuraVent fits you if you need a 5" or 7" size, or a large commercial-scale diameter.
- DuraVent fits you if a trained installer is already handling the project.
Ask your installer which one they stock. A familiar system often saves time on the day. Parts you can get quickly also help when a joint needs replacing.
What Changes on Install Day
Both systems use twist-lock joints, so assembly feels similar. The real differences show up around the edges.
Through-wall jobs need a tee, a wall support and a thimble. Ceiling jobs need a support box and an attic shield. Check that each accessory matches your brand and pipe size before you order.
How to Choose: A Five-Step Checklist
- Confirm your stove's flue size. AllFuel HST only covers 6" and 8".
- Check your stove manual. It must allow a 2100°F HT chimney.
- Map the route. Through-wall installs need a tee and wall support kit.
- Decide who installs it. DuraVent's warranty may require a professional.
- Buy one brand only. Check that every part comes from the same system.
Common Mistakes (Learn From Other People's Pain)
- Mixing brands because a part was cheaper on a marketplace.
- Guessing chimney height instead of measuring from the roof.
- Skipping the attic insulation shield, then wondering about the hot spots.
- Forgetting the second elbow strap when running two lengths between elbows, as AllFuel HST's elbow kit notes require.
A wrong part is cheaper than a house fire. It is also much less dramatic at dinner parties.
Frequently Asked Questions
Is AllFuel HST better than DuraVent?
Not across the board. AllFuel HST is a good fit for 6" and 8" stainless installs. DuraVent offers more sizes and a wider range of parts.
Can I mix AllFuel HST and DuraVent parts?
No. One retailer listing says AllFuel HST parts do not fit other brands. A Ferguson product page also advises using one manufacturer for all pieces.
What clearance do I need around the pipe?
Both systems list 2 inches to combustible materials. Always follow your specific installation manual.
Do I need a professional installer?
Check the warranty terms. DuraVent's warranty reportedly applies to professional installs only. Your local code may add its own requirements.
The Verdict
If you need 6" or 8" pipe and like all-stainless construction, AllFuel HST is a strong candidate. If you need other sizes or want a pro to handle it, DuraVent makes more sense.
Whichever you pick, match the listing to your stove and keep the whole system from one brand. Then get the install inspected.
Related Reading
- Why Roof Moss Is Quietly Damaging Your Home — useful before you cut a new roof penetration.
- What to Do When a Range Hood Insert Doesn't Fit Your Cabinet — another venting fit problem.
- Uninvited Guests: Reclaim Your Home from Rodents — worth reading if your pipe crosses the attic.
Sources
- DuraVent: DuraTech 5"–8" product page
- DuraVent: DuraTech catalog (PDF)
- AllFuel HST: 6" and 8" brochure (PDF)
- ComfortBilt: AllFuel HST elbow kit listing
- Home Depot: AllFuel HST attic insulation shield listing
- Walmart: DuraTech pipe listing with DuraVent warranty notice
- Professional Roofing (NRCA): chimney height codes
- California Mechanical Code 2022, section 802.5
- Ferguson: chimney pipe listing
- Selkirk: all-fuel chimney buyers guide (PDF)
This article is general information, not installation or legal advice. Follow your appliance manual, the chimney manufacturer's instructions and your local code.
Short answer: neither brand wins every job. AllFuel HST suits 6" or 8" installs that want all-stainless pipe and a through-the-wall kit. DuraVent DuraTech suits projects that need more sizes, more parts, or a trained installer.
Why This Comparison Matters
A Class A chimney carries flue gases from a stove that can run for hours. A weak choice here is not a cosmetic mistake.
We compared the two systems using manufacturer documents, retailer listings and code references. We did not lab-test anything. Where a claim is marketing, we say so.
What Both Chimney Systems Share
Before the differences, here is the common ground. Both are double-wall, insulated, all-fuel systems.
- Listed to UL 103 HT for 5"–8" DuraTech and for AllFuel HST's 6" and 8" sizes (DuraVent; AllFuel HST brochure).
- Twist-lock joints that need no tools.
- 2 inches of clearance to combustibles.
- A "limited lifetime" warranty, with fine print.
What "UL 103 HT" Actually Tests
UL 103 HT is a high-temperature chimney standard. It covers appliances listed for use with 2100°F chimney systems.
According to a retailer listing for AllFuel HST, the test includes a one-hour burn at 1400°F. It also adds three ten-minute burns at 2100°F.
AllFuel HST: What You Actually Get
AllFuel HST makes 6" and 8" Class A pipe, per its own brochure. It is a narrow lineup, but a focused one.
- Inner and outer walls of 0.019" 304 stainless steel.
- Ceramic fiber blanket insulation, listed as 1.18" thick by one retailer.
- A locking band included with each pipe length.
- A base wall support kit rated for up to 52 feet of chimney (ComfortBilt).
The brand also claims its walls are thicker than competitors'. Listings say 17% in some places and 25% in others. Treat that as a sales line, not a measurement.
One practical limit matters. A Home Depot listing says its attic insulation shield does not fit other brands' Class A pipe.
DuraVent DuraTech: What You Actually Get
DuraTech is DuraVent's all-fuel line. The 5"–8" range carries a combined UL and ULC listing, according to DuraVent's product page.
- Ceramic refractory blanket insulation between the walls.
- Listed to UL 103 HT and ULC S604 for 5"–8" sizes.
- Larger 10"–24" sizes, listed to UL 103 with a 1700°F ten-minute test (DuraVent catalog).
- A reduced-clearance square ceiling support box, for 6" DuraTech only.
- A stainless or galvalume outer casing, depending on the part.
Here is the catch. A retailer listing says DuraVent's warranty applies only when a trained professional installs the product. Read that before you grab a ladder.
AllFuel HST vs DuraVent: Side-by-Side
| Feature | AllFuel HST | DuraVent DuraTech |
|---|---|---|
| Sizes | 6" and 8" | 5"–8" (HT), 10"–24" (UL 103) |
| Listing | UL 103 HT | UL 103 HT and ULC S604 (5"–8") |
| Wall material | 304 stainless, both walls | Stainless inner; stainless or galvalume outer |
| Insulation | Ceramic fiber blanket | Ceramic thermal blanket, 1" |
| Clearance | 2" | 2" |
| Warranty | Limited lifetime | Limited lifetime; installer condition noted by retailers |
| Mixing brands | Listing says not compatible | Use DuraVent parts throughout |
The Rules That Matter More Than the Logo
Your brand choice sits below your local code. Chimney height, clearances and listing rules apply to both systems.
- The chimney must rise at least 3 feet above where it exits the roof.
- It must also stand 2 feet higher than anything within 10 feet.
- Factory-built chimneys must be listed and installed per manufacturer instructions.
The roofing trade body NRCA's magazine confirms the 3-2-10 height rule for IRC and NFPA 211. The California Mechanical Code states the listing and instruction rule.
NFPA 211 is a model code, so your city may enforce a different edition. Ask your local building department first.
Who Should Pick Which System
Match the product to the job, not the other way round. These profiles describe the fit, based on the specs above.
- AllFuel HST fits you if your stove uses a 6" or 8" flue and you want a through-the-wall kit.
- AllFuel HST fits you if you prefer stainless on both walls.
- DuraVent fits you if you need a 5" or 7" size, or a large commercial-scale diameter.
- DuraVent fits you if a trained installer is already handling the project.
Ask your installer which one they stock. A familiar system often saves time on the day. Parts you can get quickly also help when a joint needs replacing.
What Changes on Install Day
Both systems use twist-lock joints, so assembly feels similar. The real differences show up around the edges.
Through-wall jobs need a tee, a wall support and a thimble. Ceiling jobs need a support box and an attic shield. Check that each accessory matches your brand and pipe size before you order.
How to Choose: A Five-Step Checklist
- Confirm your stove's flue size. AllFuel HST only covers 6" and 8".
- Check your stove manual. It must allow a 2100°F HT chimney.
- Map the route. Through-wall installs need a tee and wall support kit.
- Decide who installs it. DuraVent's warranty may require a professional.
- Buy one brand only. Check that every part comes from the same system.
Common Mistakes (Learn From Other People's Pain)
- Mixing brands because a part was cheaper on a marketplace.
- Guessing chimney height instead of measuring from the roof.
- Skipping the attic insulation shield, then wondering about the hot spots.
- Forgetting the second elbow strap when running two lengths between elbows, as AllFuel HST's elbow kit notes require.
A wrong part is cheaper than a house fire. It is also much less dramatic at dinner parties.
Frequently Asked Questions
Is AllFuel HST better than DuraVent?
Not across the board. AllFuel HST is a good fit for 6" and 8" stainless installs. DuraVent offers more sizes and a wider range of parts.
Can I mix AllFuel HST and DuraVent parts?
No. One retailer listing says AllFuel HST parts do not fit other brands. A Ferguson product page also advises using one manufacturer for all pieces.
What clearance do I need around the pipe?
Both systems list 2 inches to combustible materials. Always follow your specific installation manual.
Do I need a professional installer?
Check the warranty terms. DuraVent's warranty reportedly applies to professional installs only. Your local code may add its own requirements.
The Verdict
If you need 6" or 8" pipe and like all-stainless construction, AllFuel HST is a strong candidate. If you need other sizes or want a pro to handle it, DuraVent makes more sense.
Whichever you pick, match the listing to your stove and keep the whole system from one brand. Then get the install inspected.
Related Reading
- Why Roof Moss Is Quietly Damaging Your Home — useful before you cut a new roof penetration.
- What to Do When a Range Hood Insert Doesn't Fit Your Cabinet — another venting fit problem.
- Uninvited Guests: Reclaim Your Home from Rodents — worth reading if your pipe crosses the attic.
Sources
- DuraVent: DuraTech 5"–8" product page
- DuraVent: DuraTech catalog (PDF)
- AllFuel HST: 6" and 8" brochure (PDF)
- ComfortBilt: AllFuel HST elbow kit listing
- Home Depot: AllFuel HST attic insulation shield listing
- Walmart: DuraTech pipe listing with DuraVent warranty notice
- Professional Roofing (NRCA): chimney height codes
- California Mechanical Code 2022, section 802.5
- Ferguson: chimney pipe listing
- Selkirk: all-fuel chimney buyers guide (PDF)
This article is general information, not installation or legal advice. Follow your appliance manual, the chimney manufacturer's instructions and your local code.
