One of the many benefits of using PEX tubing for plumbing projects is that it is so simple to use. PEX is inexpensive, cuts and joins easily, and requires few special tools. PEX tubing is also very easy to bend. To help PEX tubing make turns, you have a choice of three methods: 90-degree elbows, bend supports, and clamps.
PEX 90-Degree Elbow
An elbow is an L-shaped fitting that helps to create a 90-degree bend in PEX pipes. An elbow doesn't bend the PEX tubing itself. Rather, two straight sections of PEX tubing are connected to a 90-degree, L-shaped connector.
Push-fit 90-degree elbows allow you to push the PEX tubes straight into the elbow, with no other tools directly involved (you may need a PEX cutter and a PEX removal tool, however). An alternative is the crimp-fit joint system. The PEX tubes are pushed over a brass fitting. Brass rings are crimped over the ends of the PEX tubing with a special tool.
PEX Bend Support
PEX bend supports are 1/4-turn metal or plastic devices that hold the PEX in place for a 90-degree turn. Some supports have nails that allow you to secure the support to the surface below.
Bend supports generally bring the PEX to its tightest allowable 90-degree turn without folding or crimping. Turn radii differ according to PEX pipe diameter. For 1/2-inch PEX pipe, the tightest radius is usually 5 inches.
PEX clamps are individual plastic clips with attached nails. The clamps are nailed over the top of the PEX pipe. They allow for a range of turns, from tight turns similar to those produced by bend supports to wide, sweeping turns.
Equipment / Tools
- Heat gun
- Indelible marker
- Straight edge or Speed Square
- Crimper tool
- PEX tubing
- Bend support
- Push-fit or crimp-fit elbow
- PEX clamps
Bend PEX With a 90-Degree Elbow
Clean the Tube Ends
Tube ends should be square-ended, clean, and free of plastic burrs. Clean off the ends with a cloth.
Mark the Tubes
If using push-fit connectors, use an indelible marker to mark the insertion or stop point on the PEX tubes for the connector. Fittings with different brands may have different insertion depths. Consult the pipe insertion depth chart for your brand. Be sure to mark both tubes.
Push the Tube Into One Side of the Elbow
Hold the elbow in one hand and the tube in the other hand. Push the tube into the elbow. You must push in a single, firm motion. Because of push-fit connectors' internal barbs, the tube cannot be pulled out by hand. You will need to use a special remover tool.
Push the Tube Into the Other Side of the Elbow
Complete the joint by pushing the other PEX tube into the other side of the elbow.
Bend PEX With a Bend Support
Warm the PEX Tube
Though PEX tubing bends well, it can crimp if it is bent improperly. Start by warming up the PEX tubing, either by letting it sit in a warm room or by using a heat-gun at the lowest temperature setting.
Push Into One Side of the Bend Support
Push the PEX tubing into one side of the bend support. Work quickly to maintain the pliability of the tubing.
Bend the PEX Tubing
Very slowly bend the PEX tubing until it matches the curve of the bend support. If you bend too quickly, you will crimp and fold the tubing.
Push Into Other Side of the Bend Support
When the tubing curve matches that of the bend support, push the tubing into the support until it clicks into place.
Bend PEX With Clamps
Examine the Nailing Surface
When bending PEX with clamps, the nailing surface must be wood. This wood must be flat and sturdy enough to prevent the nails from pulling out. When PEX is initially bent with clamps, it places stress on the clamps.
Mark the Intended Curve
With a pencil and a straight edge or Speed Square, mark the intended curve of the PEX tubing. In most cases, you can mark the angle out with two straight lines rather than creating a curve. This makes it easier for you to determine the angle, as well.
Nail Down One Clamp
On one side of the curve, nail down a PEX clamp to the board. Be sure not to break the plastic sleeve on the clamp. Slide the PEX tube into the clamp.
If you are continuing an existing pipe rather than starting a new one, the clamp is nailed down over the pipe.
Bend the PEX Tube
Slowly bend the PEX tube to the intended position. To prevent stress from pulling out the first clamp, you may need to hold that end of the tube in place.
Nail the Second Clamp
Lay the second clamp over the PEX tube. Nail it down. Release your hold on the tube only when the clamp is firmly in place.