Except for gutter screens and strainers, Gutter Covers and Leaf Guards work by the principle of surface adhesion. Water naturally adheres to a surface over which it flows.

If you look at all solid gutter covers or gutter protectors you’ll see that they have a solid top in common. Unlike screens, there are no holes in the top horizontal surface and a curved section at the outermost edge. This top is usually located some distance above the gutter itself.

The goal is to have the water that flows from the roof onto the top of the gutter cover or gutter guard get into the gutter without letting leaves and other debris into the gutter. Logic indicates that the water would flow to the front of the cover and just keep going off into space. And yes, if the gutter guard or gutter protector were simply flat from front to back, that would be the result. To keep this from happening, the inventors of gutter covers designed an arcuate curved surface at the most front part of the gutter guard which is commonly referred to as a nose.

Have you ever poured water from a pitcher and had it trickle down the side of the pitcher instead of pouring into a cup? Then you know what I’m talking about. The water sticks to the curved surface. The design and angle of the curved edge is critical to whether the water pours into the cup or runs down the side of the pitcher.

With solid gutter covers the water flows from the back to the front of the flat surface of the gutter guard, it adheres to the downward curved portion of the gutter protector which leads it into the gutter. Of course there needs to be a space between the edge of the gutter and the curved surface of the gutter guard otherwise there wouldn’t be way for the water to enter. This space varies depending on the particular product but is usually a quarter to three-eight’s of an inch in width.

The simple basic gutter guards only have this one long curved nose surface (louver or fin) to guide or deliver the water into the gutter. They don’t have any way to filter out leaves and debris from washing into the gutter along with the water. The result is that depending on the tree cover the gutter eventually clogs with debris anyway.

As I noted earlier the design of the nose is critical. The larger the radius of the nose means the greater the flow of water that the gutter protector can handle. Likewise, the smaller the radius or curvature means the smaller the flow of water that the product will handle. The result is that a gutter cover with a small radius will only work in light rain falls.

To minimize the amount of debris that gets into the gutter with the water some gutter guards and gutter covers work with a combination of designs. In addition to the curved fin, there is a trough. The downward curved fin delivers the water to a trough. In the trough are sieve-like openings. The goal is to keep the debris that follows the curve from entering the gutter in full size form. Yet, in mid to heavy debris conditions, the debris still fills the trough where it breaks down and enters the gutter in sufficient quantity to clog the gutters.

The most advanced design of gutter guard or gutter cover combines the downward curved surface with a vertical face which has two rows of louvers. Each louver is only ¾ of an inch in width. This particular gutter guard is known as the Waterloov® Gutter Protection System. Rain water flows downward from the open curved surface, which handles both heavy and light rainfalls, and through the first row of louvers into the gutter. The rain water that is not collected by the first row of louvers flows down a bridge between the first row of louvers into the second row of louvers and into the gutter.

With the Waterloov® Gutter Protection system, nothing larger than ¾” can pass into the gutter. Any small debris that enters the gutter is small enough to be flushed down the leader so that gutters never clog and remain free flowing.

With this distinct advantage of the Waterloov® Gutter Protector design, one would wonder why anyone would ever select anything else.

Richard Kuhns B.S.Ch.E. President and CEO of R.K. Industries manufacturer of the Waterloov® Gutter Protection System.