Buyers often want to know how long the roof, electrical system, plumbing, etc. will last. The answer to these questions is not just based on the inspector’s experience; there are actually agreed upon life expectancy tables.
Although there are several we refer to, the table that is one of the most recognized for commercial properties is the Form 4327 Physical Needs Assessment. It covers many items such as roofing, heating and AC units, as well as mail boxes, signs, clothes dryers, etc. This is one key standard we use when assessing the condition of a commercial or multi-family property.
Where the tricky part comes in is determining how much longer a system will last. For the most part that has to do with how well the building and its systems have been maintained. For example, we inspected an apartment building that was 50 years old and if it continues to be maintained at the level it has been it will last at least another 50 years. We also inspected a building that was only 20 years old and in need of such extensive repairs and maintenance that it was questionable whether or not it should be torn down.
What we do in our RISK Assessment® is go over the five basic systems and the site – namely the plumbing, electrical, heating and cooling, roofing and structure – and give you our estimate of the remaining expected useful life left in each. This is partially done from experience and partially from the above mentioned table. Experience helps us determine what shape it is in now and how well it has been maintained as well as the original quality of the materials used and the quality of the installation. You don’t get those factors from a table.
Most of our inspectors have at least 30 years experience in the trades; I personally have been at it over 40 years and I can tell you, nothing replaces that much familiarity. The combination of experience and the use of agreed upon expectancy tables makes it possible to give you the very best evaluation of the property you are buying.
This question continues to require ongoing research every day. I stay in contact with industry professionals and update our information on a continuing basis. New products and methods are developed all the time. Some of the new ones don’t last nearly as long as the older ones – like the wall gas heaters you see in apartments, for instance. The new ones last maybe 10 – 15 years if they are used often. The old ones lasted 20 – 30 years or more because they were made with thicker materials.
Nothing beats a good thorough general visual inspection by a seasoned professional to get the basic understanding of what you have and how much longer it should last if properly maintained.