How many rolls do i need to fill 20ft by 10ft space ?

The rolls are 15 ft. wide so for a 20 ft. x 10 ft. area you either have seams to use the product most efficiently or some extra product. For the option with seam you would order quantity of 14 (14 linear feet). You would then cut 4 ft. of the end and cut that into two 5 ft. x 3 ft. pieces and one 5 ft. x 4 ft. piece. Place the 15 ft. x 10 ft. piece first then seam the 3 pieces with the turf grain in the same direction next to it. The other option with no seams is to order a quantity of 20 (20 linear feet) for a 15 ft. x 20 ft. piece, leaving you with 5 ft. x 20 ft. extra.