Wallbarn Flat Roof Slope Regulator - 3% Please note these slope correctors are available for all Wallbarn support pads. These wedge shaped levellers clip into the base plate and ensure the slabs do not rock or tilt as the slope is corrected at the bottom, so the force of gravity is still going directly vertical. Therefore the top of the pad is totally flat. This eliminates the often time consuming process of snapping levelling shims into quadrants and trying to get the levels correct. Avaliability • 1% - 1 in 100 slope , 0.57 ° . • 2% - 1 in 50 slope, 1.11 °. • 3% - 1 in 33 slope , 1.71 °.