Gutter Screens, Covers and Filters

GUTTER SCREENS, COVERS, AND FILTERS

A properly designed rain carrying system provides a free flowing path for rain water from the roof of a structure to be deposited away from the foundation of the structure. This helps maintain more equal moisture content in the soil under and around the structure, helping prevent foundation problems. When debris enters this system, it may restrict, or stop, the flow of water. This may cause overflowing gutters, and could actually worsen the condition of the soil around the foundation by causing unusually large loads of water to be deposited in the wrong areas. This may be caused by leaves, needles, tennis balls, paper circulars, and other wind-borne trash.

Anything which impedes the flow of water from the roof area to the exit of the down spouts, could create drainage problems. This includes most products which were originally installed to relieve the problem of debris in the rain gutter. Remember, ANYTHING which impedes the flow of water, in any way, can exacerbate the problem. It MAY be  that the best method of providing a drainage system which is not subject to clogging with debris,  is to design a system with large enough eaves trough (gutter) to transport the drain water to the downspout outlet, and then large enough downspouts to move the maximum flow of water expected “within a design range”. That means “You don’t build a church for Easter Sunday”. It usually becomes a question of which looks worse: more downspouts or debris protection.

All gutter screens, covers, filters, etc., designed to prevent the accumulation of debris in the system, usually restrict the flow of water. That said, many structures have foliage around them which seasonally output debris which will, in some cases, fill up an eaves trough so quickly and thoroughly, that it becomes a real question of how to prevent foundation problems.

If a debris protection system requires very close installation tolerances to function properly, it probably won’t work in the “real world”. In the real world: houses are not level, roof edges are not level, fascias are not straight, roof decking fluctuates up and down along its length, corners are not formed at 90 degrees, rain does not fall straight down, and wind will blow water uphill. We have, over the years, learned a few things that make the decision easier.

DIFFERENT TYPES OF DEBRIS PROTECTION

1)Solid cover systems usually require the strictest tolerances of any installation. Properly installed, on the proper structure, solid covers seem to provide the optimum protection against the widest range of debris. They are usually the most expensive systems to install. They may handle pine needles. Properly maintained are top performers.

2)Solid flat systems with varying types of screen filters usually have such a fine mesh (appears like window screen) that they clog with blossoms and light debris, requiring regular maintenance. It may handle pine needles. Is usually expensive to purchase and install.

3)Solid flat systems with louvers seem to perform better than the previous category, on very fine debris. May handle pine needles, but could be defeated by larges leaves “gluing” themselves to the surface. Also, if installed under the first row of shingles, may allow water to hydroplane over the louvers, defeating the gutter itself.

4)Screen systems, made of galvanized steel, powder coated, in coarse mesh , will not usually handle pine needles, but installed under the first row of shingles, are among the best low price performers.

5)Screen systems, made of galvanized steel, powder coated, in fine mesh, will usually handle pine needles. However, when installed under the first row of shingles on roofs of more than 12/12 pitch, will allow water to hydroplane over the screen, defeating the gutter. On those steep pitched installs, it’s preferable to have the screen flat on the top of the gutter. This also provides a “diffuser” to the water as on these installs the water may be flowing so quickly it bounces out of the gutter. The screen holds it in. You know this product as small-hole PC Screen available under several trade names.

6)Screen systems, made of aluminum, coarse or fine mesh, are usually the least expensive, least attractive, and least able to perform their function without collapsing into the gutter, especially on large roof areas.