| Company | Timeline | Status | |
| MCR Associates Limited Director • Engineer | 25 Feb 2014←11 Years→Current | Active | |
Vertech-Irvin Limited Director • Company Director | 26 Sep 2011←2 Years 2 Months→6 Dec 2013 | Dissolved | |
A.& R.Hepburn (Engineering) Limited Director • Managing Director Major Contracts | 26 Mar 2010←3 Years→6 Dec 2013 | Dissolved | |
| Richard Irvin & Sons Limited Director • Quantity Surveyor | 29 Nov 2007←6 Years→6 Dec 2013 | Active | |
