A pipe sleeve is generally one of three things: a protective ring used to keep a pipe hole open, a ring used to fill the gap between a pipe and another surface, or a covering to create a barrier between a pipe and its surroundings. These sleeves are used during the construction of a building or pipe system. Nearly every non-household pipe system has some sort of sleeve, and many household ones do as well.
This first type is commonly used during the construction or remodeling of a building. These sleeves are rings that are placed into the forms for a concrete wall. When the wall is poured, the form creates a hole that is large enough to put a pipe through. It is generally much larger than the pipe that will go through it and creates a gap.
The second type of pipe sleeve is used during the construction of a building or after the building is finished. These types fill in the gaps where pipes penetrate walls and create a barrier between the two sides through which air cannot pass. They may be made of many different materials, including polyvinyl chloride (PVC), sheet metal, or a firestop material.
The two main reasons to use this sort of sleeve are for protection from odor or fire. When the sleeve is around a water pipe, that pipe will eventually go into the sewer. By placing an airtight seal around the opening in the floor around the pipe, sewer odor won’t come back up around it. Firestops work on the same idea, except they stop fire rather than smell. As the hot air from a fire attempts to move up and out, it would naturally pull fire through the gaps around the pipe, spreading the fire faster.
The last kind of pipe sleeve is often put on during construction, but its purpose is for afterward. These sleeves protect the pipe from the environment or vice versa. The most common varieties are protective and insulating. A protective sleeve prevents damage from accidental impacts in high-traffic areas.
Some pipes carry very hot or cold materials. In some cases, it is vital that these materials stay at the current temperature, so an insulating sleeve keeps the temperature inside the pipe. On the other hand, those same materials could affect the temperature of their surroundings or cause burns if touched. Pipe sleeves protect from this as well.