/// <summary>
        /// Returns the max height of folder hierarchy
        /// </summary>
        /// <returns></returns>
        public int FindSubHeight()
        {
            //find the height of the subfolder of both roots
            int heightpl = Plans.GetHeight();
            int heightpf = ProjectFiles.GetHeight();

            if (heightpl > heightpf)
            {
                return(heightpl);
            }
            return(heightpf);
        }