For water tube, use two-hole straps or plastic clamps: a copper-bonded strap like the HoldRite CPS050 on copper, and a plastic clamp like the HoldRite 221 on PEX. One-hole straps are mostly sold for electrical conduit. The IRC also limits spacing, for example 32 inches for small PEX and 6 feet for small copper, and bans strapping that promotes galvanic action.
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This guide covers straps and clamps for supply and drain piping in homes.
One-hole vs two-hole at a glance
| Strap | Fastening | Where you see it |
|---|---|---|
| One-hole strap | One screw on one side; the other side hooks or bears against the surface | Mostly electrical conduit and rigid pipe; quick to install where only one side is reachable |
| Two-hole strap | A screw on each side of the pipe | Copper and plastic water tubing runs on walls, joists and framing |
| Plastic two-screw clamp | Two screws through a plastic body | PEX, copper and CPVC where the pipe must be isolated from metal |
A two-hole strap clamps the pipe evenly from both sides. A one-hole strap holds it from one side, which is faster but gives less even clamping. For plumbing tube, HoldRite and other support makers list two-hole straps and plastic clamps; in our Amazon searches on October 15, 2026, most one-hole straps were listed for electrical conduit.
What the code asks of any strap
IRC Section P2605.1 (codes-conv.iccsafe.org) says piping must be supported to keep alignment, prevent sagging and allow for expansion and contraction. Hangers and anchors must be strong enough for their share of the pipe and its contents and wide enough not to distort the pipe.
The same section says hangers and strapping must be of approved material that will not promote galvanic action. In practice that means copper or copper-bonded straps, or plastic, on copper tube; not bare steel or galvanized straps.
It also requires rigid bracing on horizontal drain or waste pipes 4 inches and larger where a fitting changes direction more than 45 degrees, to resist movement in the direction of flow. A light strap alone does not meet that.
How far apart: IRC Table P2605.1
| Pipe | Horizontal | Vertical |
|---|---|---|
| Copper tubing, 1-1/4 in. and smaller | 6 ft | 10 ft |
| PEX, 1 in. and smaller | 32 in. | 10 ft* |
| CPVC, 1 in. and smaller | 3 ft | 10 ft* |
| PVC pipe | 4 ft | 10 ft* |
| ABS pipe | 4 ft | 10 ft* |
*The table’s footnote says that for sizes 2 inches and smaller, a guide must be installed midway between required vertical supports to stop the pipe moving sideways.
So a 1/2-inch PEX run needs a strap or clamp at least every 32 inches horizontally, while 1/2-inch copper can go 6 feet. Your local code may differ; check the edition your city or county uses.
HoldRite CPS050: copper-bonded two-hole strap for copper
Choose the HoldRite CPS050 for 1/2-inch copper tube. HoldRite’s copper-bonded two-hole strap page (holdrite.com) says it secures copper tube size pipe in horizontal and vertical runs and lists the CPS050 for 1/2-inch CTS at 1.9 × 0.7 inches, with CPS075 and CPS100 for 3/4 and 1 inch.
Because it is copper-bonded, it suits the no-galvanic-action rule on copper tube. On October 15, 2026, the standard new offer sold by Amazon.com showed stock for a 50-pack, model CPS050Z50.
Skip it on PEX; use a support listed for plastic tube, such as the plastic clamp below.
Check HoldRite CPS050 copper two-hole strap 50-pack on Amazon →
HoldRite 221: plastic suspension clamp for PEX, copper or CPVC
Choose the HoldRite 221 for 1/2-inch PEX, or anywhere you want plastic between the pipe and a metal surface. HoldRite’s suspension clamp page (holdrite.com) lists it for copper, PEX and CPVC, mounting to wood or metal studs or a Stout Bracket with two screws, and names dissimilar metal isolation, through-stud isolation, mid-span support and stub-out support among its uses. It is IAPMO UPC and IPC listed.
The 221 fits 1/2-inch CTS; HoldRite lists the 222 for 3/4 inch and larger sizes up to 2 inches.
On October 15, 2026, the standard new offer sold by Amazon.com showed stock for a 10-pack, model 221Z10.
Check HoldRite 221 suspension clamp 10-pack on Amazon →
Strapping PVC and ABS drain pipe
Drain pipe follows the same table. IRC Table P2605.1 (codes-conv.iccsafe.org) lists PVC and ABS pipe at 4 feet maximum horizontal spacing and 10 feet vertical, with the mid-height guide for 2-inch and smaller pipe. Cast iron is listed at 5 feet horizontal, increased to 10 feet where 10-foot lengths are installed.
Horizontal drains also need to hold their slope. A strap every 4 feet keeps a PVC run from sagging into a belly where water and solids can sit.
On plastic drain pipe, galvanic action is not a concern, so either plastic or galvanized hanger strap works under joists. Choose the Oatey 33925 3/4-inch × 25-foot plastic hanger strap when you want a strap that will not corrode in a damp crawlspace. On October 15, 2026, the standard new offer sold by Amazon.com showed limited stock with model 33925.
Wrap the strap around the pipe and fasten both ends to the framing so the pipe cannot swing, and keep the strap snug but not so tight that it pinches or deforms the pipe.
Check Oatey 33925 plastic hanger strap 3/4 in. x 25 ft on Amazon →
When a one-hole strap makes sense
One-hole straps are quick when you can reach only one side of the pipe, such as tight against a corner. If you use one on plumbing, make sure the material is compatible with the pipe, the strap fits the pipe’s outside diameter and the spacing meets the table above.
Do not use an electrical conduit strap sized for conduit on water tube without checking the fit; conduit and copper tube of the same nominal size have different outside diameters.
For long runs or heavier pipe, use two-hole straps, clamps or hangers. Our clevis vs split-ring hanger guide covers overhead hangers.
Fastening straps to the structure
Into wood framing, use screws long enough to bite firmly. Into concrete or block, use a concrete screw or anchor sized for the strap hole; our concrete anchors guide covers sizes.
Do not overtighten a strap on plastic pipe. The code asks supports to allow for expansion and contraction, and PEX in particular moves with temperature.
Where pipe passes through studs or joists near the face, protect it with nail plates; our nail plate guide explains where they are required.
Frequently asked questions
What is the difference between a one-hole and a two-hole strap?
A two-hole strap is fastened on both sides of the pipe for even clamping. A one-hole strap is fastened on one side and is mostly sold for electrical conduit.
Can I use galvanized straps on copper pipe?
No. IRC P2605.1 says hangers and strapping must not promote galvanic action. Use copper, copper-bonded or plastic supports on copper.
How far apart should PEX straps be?
IRC Table P2605.1 lists 32 inches maximum horizontal spacing for PEX 1 inch and smaller.
How far apart should copper pipe straps be?
For copper tubing 1-1/4 inches and smaller, IRC Table P2605.1 lists 6 feet horizontal and 10 feet vertical.
What strap is best for PEX?
A plastic clamp such as the HoldRite 221, which is listed for PEX, copper and CPVC and isolates the pipe from metal.
How we chose
This document-based guide makes no hands-on testing claim. We read Section P2605 and Table P2605.1 of the 2024 IRC and HoldRite’s current two-hole strap and suspension clamp pages. On October 15, 2026, both linked standard new offers sold by Amazon.com showed stock. Read our selection method and about Plumbing Picks.
Primary sources
- 2024 IRC Chapter 26, Section P2605 (codes-conv.iccsafe.org): support rules, no galvanic action, 4 in. bracing, Table P2605.1 spacing. Model code; local adoption varies.
- HoldRite copper-bonded two-hole pipe strap (holdrite.com): CPS050/075/100 sizes and uses.
- HoldRite suspension clamp (holdrite.com): 221–228 sizes, two-screw mounting, isolation uses, IAPMO listing.