In practice, Pipe Installation is not just used for containing heat. It is also used to control cold pipe systems and keep them functioning properly and in good repair. The first and possibly most important concern is controlling condensation. When the cold pipe system contacts the air, condensation will form once the pipe system is below the dew point of the ambient air. This condensation can adversely effect the quality of the pipes and cause mold, ice, and degradation of the pipe material.
In general, there is a common misconception that cold insulation materials can be the same as insulation for hot systems. However, in reality, there are several differences between cold system insulation needs and hot system insulation needs.
Firstly, the closed cell structure. Closed cell structure is necessary to avoid wicking behavior. Usually, most open celled material used for hot pipe systems allows water to enter because the heat will cause the moisture to evaporate before it can corrode the metal. While this same moisture ingress is very detrimental to cold systems because the moisture does not evaporate.
Secondly, the effective water vapor barriers. This a key part of avoiding metal degradation and preventing condensation from gathering directly on the metal surface. A solid, flexible water vapor barrier is necessary to prevent water from condensing on the metal pipe surface. But this type of water vapor barrier is not necessary for hot systems.
Thirdly, the thermal bridging potential. Often, there are strangely shaped or bent connections that are left uninsulated because their size and shape make them hard to find insulation for. Examples include expansion joints, triple duty valves, and flange sets. These types of joints are potential thermal bridge points if left uninsulated. In cold systems, they will collect moisture. So bendable or flexible insulation is needed to protect against this.
At present, there are several types of materials that can be used to insulate cold systems. When combined with the appropriate vapor barriers, materials like fiberglass, mineral wool and cellular glass are rated for low temperatures. Because of their flexible and closed-cell nature, foam polyurethanes are also popular for insulating cold pipe systems. Besides, there are many types of flexible and rigid insulation techniques for cold pipe systems that involve a number of variations in materials used.
However, getting to the actual pipe surface for maintenance purposes often involves damaging or permanently removing the insulation that was applied. This can get rather expensive, especially if the area that needs to be reached is a valve that needs to be freely accessible. Fortunately, there are several removable insulation options available in the market these days which can make reaching these areas easier and less costly.