| Company | Timeline | Status | |
Evans Reid Mechanical Sales Limited Director • Engineer | 1 Oct 2014←4 Years→3 Sep 2019 | Dissolved | |
| G.M.S. Thermal Products Limited Director • Unreported | 22 May 2013←12 Years→Current | Active | |
| McCallum Limited Director • Unreported | 24 Aug 2007←18 Years→Current | Active | |
| McCallum Domestic Limited Director • Unreported | 13 Oct 2004←21 Years→Current | Active | |
| McCallum Water Heating Limited Director • Unreported | 21 Nov 2002←22 Years→Current | Active | |
| McCallum (Barrhead) Limited Director • Unreported | 12 Nov 2002←23 Years→Current | Active | |
| GRM Manufacturing Limited Director • Unreported | 11 Oct 2002←23 Years→Current | Active | |
| McCallum Calorifiers Limited Director • Unreported | 31 Dec 2000←24 Years→Current | Active | |
