Insulation Systems: Reasons for Failure

Alec J. Rexroat

May 1, 2008

In the November 2007 issue of Insulation Outlook, “Insulation Systems: Doomed From the Start?” discussed some conditions that can doom mechanical insulation to failure (see The article highlighted the term “value engineering” as it pertains to mechanical insulation, considered how mechanical insulation seems a forgotten technology, and described the effects of compressed schedules that do not give many trades sufficient time to install their systems properly. The article also discussed careless mechanical system installation, including improper installation of insulation materials and carelessness on the part of the insulation contractor. With that as background, this article provides possible solutions to the problems of mechanical insulation failure, starting at the beginning of the construction process. At every subsequent stage of the process, this discussion will shed light on mechanical insulation, “the forgotten technology.”

The importance of the owner and architect recognizing the value of mechanical insulation when developing a project’s construction and completion schedules cannot be overemphasized. The mechanical insulation portion of the construction process is usually at the end of the schedule. The window for the insulation contractor may be smaller as a result of delays at the front end, but no extensions typically are given at the back end. Insufficient time to properly complete the insulation process equals potential for mechanical insulation failure. The owner and architect must recognize the importance of every trade in the construction process. Mechanical insulation is not the only trade that suffers from poor project scheduling. The entire project will suffer if scheduling is not properly considered from the beginning. Many problems can be avoided by considering the trades that get involved at the end of the schedule when planning at the beginning. Specifically, mechanical insulation will be less likely to fail if adequate time is afforded the installing contractor.

With a realistic construction schedule, attention turns to the design team and the mechanical engineer to prepare the drawings and documents for the project. In far too many cases, the mechanical engineer will go to the library, pull an old insulation specification off the shelf, and put it into the bid package. Much of the included specification will not have anything to do with the current project, but it is quicker and easier than developing a specification for the particular job. Specifications for old projects that are used as generic specs for all projects have a tendency to allow the engineer to avoid considering all of the important ramifications of a specific job as it relates to the mechanical insulation. Has the humidity of the space as it relates to the use of the building and the equipment that will be installed been considered? How about new materials available on the market? Do the specifications take into consideration the space available to install mechanical insulation? Have the design criteria—as they relate to mechanical insulation—been adequately considered? If these items are not identified and addressed at the beginning stage of the process, there is a likelihood that failures will occur at the end. The mechanical insulation will become very important when the systems fail and the owner, architect, engineer, general contractor, and mechanical contractors are all trying to figure out why.

Getting It Right the First Time

As an example, consider a building that has been beautifully designed by the architect. The mechanical engineer has identified the proper insulation materials specified for the project based on the use of the building and the conditions under which the mechanical systems will function. The construction process is beginning. The mechanical contractors have been selected and have begun the process of installing pipes for the plumbing and heating systems, as well as the sheet metal for the ventilation. The general contractor has decided that he would rather allow the mechanical contractors to award the mechanical insulation so that he does not have to handle it. The mechanical contractors request insulation prices from various contractors who specialize in installing insulation materials. The insulation contractors are asked to “sharpen their pencils” because everyone has been asked to reduce their prices to get the project under budget. In short, the insulation contractors are asked to value engineer the project to bring it in under budget.

As described in the earlier article in this series, value engineering in far too many cases means either eliminating the insulation or reducing the thicknesses of the materials to reduce the install cost of the project. The owner of the building has no idea that this value engineering is taking place. The owner thinks the final product is going to be the quality building that is being paid for, but when value engineering comes into play, the integrity of the mechanical insulation system is frequently compromised. There are, of course, times when a different material can substitute for the one specified and reduce project costs. All too frequently, however, quality is what gets compromised.

In this case, the owner insists that the mechanical insulation not be compromised: He wants the type and thickness of materials for which he is paying. The bidding process is now complete, and a contractor has been selected. The owner, architect, and mechanical engineer all have been educated to understand that value engineering when it comes to insulation is a bad idea. The project will go forward with the quality specification the engineer selected. Those involved with this project are not forgetting the insulation.

The general contractor (GC) is in a very influential position at this point in the process. If the GC understands the importance of mechanical insulation, he or she can instruct all mechanical trades to install their systems with insulation in mind. The GC can require that the insulation contractor attend the job meetings—which works much better when the GC has made the award and controls the insulation. The GC can insist that the systems be installed with adequate clearance for the insulation and can instruct the other trades to remember that the mechanical insulation must be installed properly—therefore, they are obligated to pay attention to the insulation process.

Now, the piping systems are being installed, and the core openings are not in perfect center. The pipe will fit; it just will not be centered. The insulation contractor will have to make it work. The selected insulation contractor has taken the time to visit the project in the early stages of construction and has noticed this problem. The insulation contractor will discuss this issue with the mechanical and general contractors to ensure that the pipe systems are installed properly to allow for the pipe insulation to be installed. The problem is rectified early in the process. The same thing happens when the pipes are installed too close together to allow for the specified thickness of the insulation materials. It happens again when the sheet metal is installed directly on the chilled water piping system. All parties in the construction process are put on notice by the insulation contractor that the mechanical systems must be installed with adequate clearance to allow for the specified insulation thicknesses to be installed. If this does not happen, the insulation contractor cannot be held responsible for potential failures in the future.

There is no question that in the construction business, nothing is perfect. Mechanical insulation contractors do not expect perfection but can and do expect that their portion of the project be considered by all parties. The National Insulation Association (NIA) and its affiliated regional associations are working to shed light on mechanical insulation (the forgotten technology). Owners, architects, mechanical engineers, and mechanical contractors cannot be expected to be as vigilant about insulation as NIA members are. It can be expected, however, that at this time in history—with the cost of oil and gas going up daily—all parties involved in the construction process become aware of the value of mechanical insulation and address it accordingly. Properly worked-out schedules, with attention paid to details regarding insulation types and thicknesses, as well as the proper clearance for material installation, will help contractors avoid many problems at the end of the project.