Galvanized pipes have a general life expectancy of 50 years, but this can be shortened considerably by the amount of minerals in the water supply. Columbia has naturally soft water, and galvanized pipes here tend to last longer. Other areas of the country such as Southern California have rather hard water, and as a consequence, galvanized pipes won’t last as long there. Two things happen to galvanized pipes as they age.

First, minerals tend to slowly build up on the inner walls of the pipe decreasing the inside diameter. In extreme cases, this can slow the water flow to a trickle.

The other common problem with galvanized pipes is corrosion at the joints. In the process of cutting the threads for the pipe fittings, the protective galvanizing is cut away exposing bare metal. Over time, these threaded joints will corrode and eventually break. In the case of your 80 year old house, if the pipes are original I would definitely consider replacing them. If you are not sure how old they are, I recommend that a qualified home inspector examine them and look for signs of corrosion at the fittings, and check for low water flow at all of the faucets.