Slide the Pex pipe into the formed foam pipe insulation. Formed foam pipe insulation is available in lengths up to six feet. Butt multiple lengths of formed foam pipe insulation together end to end. Cut lengths of formed foam pipe insulation with a pair of scissors or a utility knife to fit tightly into place where butting is required.
Remove the plastic adhesive strips at the same time for each individual length of formed foam pipe insulation to expose the adhesive. Be sure the seams for each length of insulation are fully adhered to ensure proper insulative value.
Tape the butt seams in between each length together with insulating tape to reduce heat loss through these seams.