Push-fit fittings

Entry in Joining methods · Updated October 29, 2026 · Written by the Know Your Pipes editors from the sources listed under References

Push-fit fittings, also sold as push to connect fittings, are plumbing fittings that join water tube when the tube end is pushed into the fitting, where an internal locking device holds it and an O-ring or gasket forms the seal.^[2] No heat, cement, threads or crimping tool is needed to make the joint.

The performance standard for these fittings in North America is ASSE 1061, Performance Requirements for Push-Fit Fittings, first published in 2006 and revised in 2011 and 2015.^[1] It applies to fittings intended for hot and cold drinking-water distribution and hydronic heating systems in homes and commercial buildings.^[1]

1 How the joint works

Inside the fitting body sit two working parts. A locking component, such as a toothed grip ring, snap ring or twist collar, lets the tube slide in but resists pulling back out, and an O-ring or gasket presses against the outside of the tube to keep water in.^[2] On PEX and other flexible tubing, a support liner (stiffener) goes inside the tube end so the plastic keeps its round shape under the seal.^[2]

Because the seal rides on the outside surface of the tube, the condition of the tube end matters. One maker's instructions call for a square cut that leaves the tube round, and for burrs to be removed from both the inside and outside edges, since a sharp edge can damage the O-ring.^[3] The same instructions call for a depth mark measured from the cut, so the installer can see that the tube went fully home.^[3]

2 Tubing and standards

ASSE 1061 covers fittings up to 2 in that work with one or more of four tubing families, each made to its own dimensional standard.^[2] A given fitting may be listed for only some of them, so the markings and the maker's literature decide which tube it accepts.^[2]

The stiffener column comes from one maker's sheet, which lists its fittings for PEX, CPVC and Type M or thicker copper.^[3] That sheet's approximate insertion depth is 15/16 in for 1/2 in tube, 1 1/8 in for 3/4 in and 1 1/4 in for 1 in, and it allows only water as a lubricant.^[3] Depths differ between makers, which is why the chart on the package governs.

ASSE 1061 also sets minimum temperature and pressure ratings and marking rules, but the rating printed on a particular product comes from its maker and can differ between product lines.^[2] Related materials are covered under copper pipe types K, L and M and CPVC pipe.

3 Concealment, burial and removal

The same maker's instructions call for the finished system to be pressure tested for 24 hours before it is buried or enclosed in a wall.^[3] Fittings placed underground must be tightly wrapped and sealed in an impervious material such as chloride-free tape, kept away from groundwater and backfill, and bedded in backfill free of rocks and sharp debris.^[3] Whether push-fit joints may be concealed or buried at all is a local code question; see plumbing codes: IPC, UPC and IRC.

Many push-fit fittings can be taken apart. In the instructions cited here, the line is depressurized and drained, a removal clip presses the release collar, and the tube is pulled out with a slight twist; the tube end is then inspected and any damaged section cut off before the fitting goes back on.^[3]

4 Use as an emergency repair

Push-fit is the one joining method in this reference that a homeowner may use for an emergency repair, such as rejoining a split section of pipe after a freeze, and only where the fitting maker's instructions and the local plumbing code allow it. The main water valve has to be off first; see shutoff valves and burst pipe first steps. A permanent repair, or any joint that will be closed into a wall or slab, is work for a licensed plumber who can confirm the fitting's listing and the code's rules.

Push-fit couplings, tees and adapters are stocked by size and tube type at plumbing supply houses; PlumbingSupplyAndMore's push fittings category (PlumbingSupplyAndMore has the same owners as this reference) is one example. For comparison with heat-made copper joints, see soldered sweat joints.