Mapei Mapeguard Um Underlayment Membrane 54 Sq.ft - Shop Now for the best prices and deals at Squarefoot Flooring, your trusted flooring store near me and you serving Mississauga, Barrie, Toronto, Oakville, Niagara Falls, Brampton, Vaughan, Milton, Richmond Hill, Markham, Newmarket, Burlington, Hamilton, Guelph, Ontario, and across Canada. Category: Tile Membranes. Brand: Mapei. SKU: 94285-05.