In roofing, a layer of hot bitumen mopped between plies of roofing felt. Full mopping is the application of bitumen by mopping in such a manner that the surface being mopped is entirely coated with a reasonably uniform coating. Spot Mopping is the procedure of applying hot bitumen in a random fashion of small daubs, as compared to full mopping. Sp... Found on http://www.encyclo.co.uk/local/20933
The application of hot bitumen with a mop or mechanical applicator to the substrate or to the felts of a built-up roof membrane. Found on http://www.rbroof.com/glossary-of-terms