What Type Of Thread Is Garden Hose: GHT Vs NPT Guide

Most garden hoses use 3/4-11.5 NH (GHT) straight threads with a washer.

If you have ever asked what type of thread is garden hose, you are not alone. I’ve installed hoses on homes, farms, and job sites for years, and the same question keeps coming up. This guide breaks down the exact thread standard, how it seals, and how to avoid leaks or cross-threading. Read on for a complete answer to what type of thread is garden hose, with clear tips you can use today.

What Type of Thread Is Garden Hose? The Basics

In North America, most garden hoses use 3/4-11.5 NH, also called GHT. NH stands for National Hose. It is a straight (parallel) thread, not tapered. It seals with a flat rubber washer in the female coupling, not with thread sealant.

People often search “what type of thread is garden hose” when they buy adapters or nozzles. The short answer is GHT in the US and Canada. The male spigot usually has GHT. Your hose has a female GHT on the supply end and a male GHT on the tool end.

Key facts at a glance:

Size: 3/4 inch nominal, about 1.0625 inches outside diameter on male threads
Threads per inch: 11.5 TPI
Form: Straight thread (parallel), sealed by a washer, not by tapered thread pressure
Typical names: GHT, NH, NHR, “hose thread”

North American Standard: GHT/NH Explained

GHT, or NH, is the garden hose thread used across the US and Canada. The standard uses straight threads so you can tighten to a firm stop against a gasket. This makes hose connections quick, repeatable, and friendly to home use.

Do not use thread tape to seal GHT-to-GHT joints. The seal happens at the washer face. If you ever wondered “what type of thread is garden hose,” this is the detail that matters most in day-to-day use.

Hands-on tip:

Keep spare 3/4-inch hose washers on hand. A fresh washer is the fastest fix for drips.

Global Variants: BSP and Other Systems

Outside North America, garden hose fittings often use BSP threads. You will see BSPP (parallel) and BSPT (tapered). The most common are 3/4 BSP and 1/2 BSP in Europe, the UK, Australia, and many other regions.

BSP and GHT are not directly compatible. The pitch and thread form differ. When traveling or importing tools, use a GHT-to-BSP adapter. It saves time and prevents damage.

Practical note from the field:

I once tried to mate a UK spray head to a US hose. It felt close but would not seat. A cheap GHT-to-BSP adapter fixed it in seconds.

GHT vs NPT: Why They Don’t Mix

NPT is a tapered pipe thread used on plumbing. GHT is a straight hose thread used on outdoor water gear. They are not the same and will not seal together by themselves.

If you must join them, use a GHT-to-NPT adapter. For example, a rain barrel may have a 3/4 NPT outlet. You can add a 3/4 NPT to 3/4 GHT adapter to connect a garden hose. If you are asking what type of thread is garden hose for this setup, the answer stays GHT; you just need the right adapter in between.

Sealing and Sizes: Washers, O-rings, and Diameters

A proper GHT joint seals at the flat washer. The washer sits inside the female coupling. When you tighten by hand, the washer compresses and forms a water-tight face seal.

Helpful details:

Washers: Standard flat rubber works. For longer life, try Buna-N or EPDM.
O-rings: Some quick-connects use O-rings. Keep a spare set in your toolbox.
Diameter cues: 3/4 GHT male is about 1.0625 inches OD. 3/4 NPT is smaller on the small end and uses a 14 TPI tapered thread, not 11.5 TPI.

If you catch yourself wondering “what type of thread is garden hose” when a joint leaks, check the washer first. Most drips vanish with a new washer.

Adapters and Quick-Connect Options

Adapters help you bridge systems, sizes, and tools. Common types include:

GHT female to GHT male (extenders, thread savers)
GHT to NPT (for pumps, filters, rain barrels)
GHT to BSP (for imported nozzles or European timers)
Quick-connect sets (snap-fit couplers for fast swaps)

I keep brass adapters in my truck. Brass lasts longer than plastic under sun and heat. If you type what type of thread is garden hose when shopping, look for “3/4 GHT” on adapters to be sure you have the right parts.

How to Measure and Identify Your Thread

Not sure what you have? Follow these quick checks.

Count threads per inch. GHT has 11.5 TPI. Use a thread gauge or a ruler and count over one inch.
Check the seal style. A flat washer in the female side points to GHT or BSPP style, not a tapered seal.
Measure diameter. A 3/4 GHT male measures about 1.0625 inches OD.
Feel the fit. A proper GHT pair tightens to a firm stop at the washer face.

When you are stuck and ask “what type of thread is garden hose,” these checks point you to the answer fast.

Real-World Tips, Mistakes, and Use Cases

From years in the field, here are my go-to tips:

Hand-tighten first. Use light wrench pressure only if needed. Over-tightening crushes washers and cracks plastic.
Replace washers each season. It is cheap and stops surprise leaks.
Use a splitter with valves for two hoses. Choose full-port valves to keep flow high.
Protect threads. Cap unused male ends to keep grit out. Grit can cause cross-threading.

A hard lesson I learned early: I once forced an NPT fitting into a hose coupling. It felt snug but leaked badly and ruined the threads. The right GHT adapter would have saved time and money. If you wonder what type of thread is garden hose in a mixed setup, confirm before you twist.

Troubleshooting Leaks and Cross-Threading

Common leak causes and fixes:

Missing or worn washer. Replace the washer. Check for cracks or flattening.
Cross-threading. Stop, back off, and re-start by hand. The joint should spin freely at first.
Oval or damaged couplings. Replace the coupling or use a short repair hose leader.
Mismatch of systems. Use the correct GHT, NPT, or BSP adapter.

If a neighbor asks, “what type of thread is garden hose,” share that it is GHT in North America. Then hand them a spare washer. It solves most problems in seconds.

Safety, Materials, and Longevity

Materials matter. Brass couplings handle sun, grit, and heavy use. Plastic is light and cheap but can crack. Stainless steel resists corrosion but costs more.

For drinking water or RV use, choose lead-free, drinking-water-safe hoses and fittings. Store hoses out of direct sun to protect rubber and washers. If you are pricing parts and still asking what type of thread is garden hose, remember that the thread is GHT; quality comes from material choice and care.

Frequently Asked Questions of what type of thread is garden hose

What type of thread is garden hose?

In the US and Canada, it is 3/4-11.5 NH, also called GHT. It is a straight thread that seals with a flat washer, not with tape.

Is garden hose thread the same as NPT?

No. NPT is tapered and uses thread interference to seal. GHT is straight and seals at a washer, so you need an adapter to join them.

Can I use tape or paste on garden hose threads?

You do not need it for GHT-to-GHT joints. The seal is at the washer; tape can even get in the way.

What type of thread is garden hose outside North America?

Many regions use BSP threads for hose gear. Use a GHT-to-BSP adapter if you want to mix parts.

How do I measure my garden hose thread?

Count threads per inch and check diameter. GHT has 11.5 TPI and a male OD of about 1.0625 inches.

Why does my hose leak at the faucet?

The washer may be worn, missing, or not seated. Replace the washer and hand-tighten to a firm stop.

Conclusion

You now have the clear picture: in North America, garden hose fittings use 3/4-11.5 NH (GHT) straight threads that seal with a washer. Around the world, many hoses use BSP, and you can bridge systems with simple adapters. When in doubt, check thread pitch, diameter, and seal style.

Put this guide to work today. Keep spare washers, choose brass adapters, and confirm thread types before you connect. If this helped you answer what type of thread is garden hose for your setup, share it with a friend, subscribe for more hands-on guides, or leave a comment with your gear and goals.