The materials selected when choosing different gutter protection products are crucial to the performance and longevity of the system. When deciding on gutter guards, gutter covers, gutter screens, or gutter filters, one of the factors that must be considered is the environmental conditions the parts will see during their lifetime.
The parts will be outdoors, day and night, anywhere in the U.S., Canada, or wherever else the suppliers ship the product. While there may not be many residential buildings at these exact sites, the range of temperatures in the U.S. is extreme. A temperature of 135°F has been recorded at Death Valley, California. At the other extreme, Prospect Creek, Alaska has a recorded low of –83°F. That is a range of over 200°F. Remember, those are air temperatures. At the high end, a dark object in direct sunlight in the middle of the day may be even hotter. Some states have extremely large seasonal temperature changes. North Dakota has seen summer highs in excess of 114°F and winter lows of –54°F, a range of almost 170°F.
When designing such parts they have to be strong enough to hold up in the heat (without melting or sagging) and be resilient enough to not become extremely brittle and crack at low temperatures. Many materials, particularly many plastics, just won’t perform throughout a wide temperature range. They soften and sag in high heat. They also become very brittle in extreme cold. Any unusual stress under these conditions may cause them to crack.
Another major factor is sunlight. A cover or guard will be exposed to many years of direct sunlight. Many materials will be affected by long-term exposure to the ultraviolet light in sunlight. Once again, nonmetallic materials are often affected greatly, making some plastics particularly difficult to use.
Many roof parts are made from metal. The principal ones are aluminum, steel, and copper. In order to make steel more rust resistant, it is usually galvanized. Powder coated steel is also used in some cases. Metal is usually stronger and longer lasting than most plastics. They are normally not affected by exposure to weather and sunlight. They can, however, be dented by mistreatment or falling objects. Some systems are manufactured using polypropylene or PVC. Many of these products seem to perform satisfactorily.
Another popular product for leaf guards is the gutter filter. This uses polyether-polyurethane foam as the filter material. The material is open cell foam. Water freely flows through the foam. A block of the foam material is shaped to fit the K-style or half-round gutter. When inserted into the gutter the top of the foam acts like a cover, catching all debris. The foam material dries quickly after the rain passes, allowing the debris on top to also dry out. Normal wind will then blow leaves and any other debris off the foam filter. Filter products should be checked to make sure they are safe guarded against Ultra violet rays
Some discount-type items, which are used in economy or low-cost products, are made of plastics that will not stand up well to the temperature cycles and UV exposure. They fade, lose color, and become stiff and brittle, even at moderate temperatures. They break and then have to be replaced if, for instance, a branch falls onto the rain gutter after an ice storm.
In order to match or accent a house, roofing parts are often painted. Such paints must also survive the range of environmental conditions. Most paint colors will fade with extended exposure to the ultraviolet light in sunlight, every day, all day.
Some aluminum or steel covers or guards are painted and can be matched to the color of your rain gutters. Others, such as one where a portion of the cover or shield is inserted under the shingle, have a painted surface that simulates different shingle covers and patterns.
Another factor that has to be considered is possible galvanic corrosion. Certain metals, when placed in contact with one another, create a small electric current—that is what makes a battery possible. This current will create corrosion of the metal parts, damaging some of the metal parts. The different components of the system (gutter, cover, or screen clamps that come into contact with the metal parts and fasteners) must be selected to avoid this problem.
Sound complicated? We will try to help make it easy for you. GutterSupply.com has a great leaf guard compatibility chart that will help you understand what products work in different situations. The chart includes 13 different gutter guards, gutter covers, gutter screens, or gutter filter products. It identifies whether they are best for K-style or half-round systems and compatible information for different roof types. The three different metal materials are also included. To view the chart, go to GutterSupply.com. If you still have compatibility question, they can help.