Buildings Sectional & Portable in Marton, Welshpool, Powys

History. 4m Portable Buildings began in 1992 by two individuals who had, at the time, already built up many years experience in the portable buildings industry. To date between them they now have over 75 years of experience to call upon and all of our staff are time served craftsmen. Over that period the company has seen many changes and developments to the construction of portable buildings but it has never lost sight of the core aim of building high quality buildings to the customers requirements. Although 'off the peg' designs are available no two projects are the same and this is what has led to 4m focusing on what the clients requires.