A tie retaining wall constructed of timbers. The heights of these walls can vary from six inches to four-feet without an engineer’s approval. If you want to build beyond four feet tall on a single wall an engineer’s approval is required. Terracing is another possibility. When you have finished construction on the first wall you may return in four feet horizontally which will permit you to build another four foot wall and so on until the desired height is obtained. There are two types of timber tie retaining walls:
30 year tie: Is constructed of 6 inch by 6 inch yellow pine. This type is also referred as a rough tie because it is unfinished with slight bends in the edges, which may cause splinters to the touch. Manufacturer rated for 30-year life expectancies under the proper conditions.
40 year tie: Is constructed of 5.5 inch by 5.5 inch fine milled yellow pine tie. The finish is properly sanded and the edges are extremely straight (no splinters). The appearance of these ties are slightly more pleasing to the eye. Manufacturer rated for 40-year life expectancy under the proper conditions.