  In this paper we generalise the theory of real vector bundles to a certain
class of non-Hausdorff manifolds. In particular, it is shown that every vector
bundle fibred over these non-Hausdorff manifolds can be constructed as a
colimit of standard vector bundles. We then use this description to introduce
various formulas that express non-Hausdorff structures in terms of data defined
on certain Hausdorff submanifolds. Finally, we use \v{C}ech cohomology to
classify the real non-Hausdorff line bundles.
