abstract architectural backdrop background barrier brick brick-wall bricks brickwork cement coloring colors colouring colours constructed corner corner-wall exterior external firm fixed linear lines merger merging mixed mortar perspective perspectives repaired secure security smooth solid standard strength strong style surface surfaced surfaces texture textured textures variation varied various wall wallpaper basic color colored colour coloured covered covering green Rendered rendering traditional-brick-wall walled well-built angles appearance backgrounds blocks contrast contrasts cracks discoloration fitted foundation foundational growth height high large limestone moss old plants retaining retaining-wall stone stones stonework variations variety contours lichen rock rock-face rockface rough windows builders building concrete construction-work holes hollow rectangular uneven