Roofs in damp environments are susceptible to moss growth. Moss thrives on portions of roofs shaded by overhanging tree branches and nearby vegetation. Besides being an obvious eyesore, moss roots permeate roofing materials until roofs eventually deteriorate. Copper is a natural fungicide and herbicide used to prevent moss growth. Installing copper strips on roofs is a method of controlling moss without harming roofing materials or the environment. Control roof moss with copper strips by using certain supplies and techniques.
Cut sheet copper into four long strips using tin snips. Make each copper strip 20 cm (8 inches) wide and 3 m (10 feet) long.
Slide a putty knife underneath the row of shingles directly below the roof's ridge. Loosen the shingles' self-sealing tabs to make room for the copper strips.
Insert a copper strip underneath the row of shingles directly below the roof's ridge. Push the strip back until it touches the roofing nails attached to the shingles. Make sure at least 5 cm (2 inches) of the copper strip is exposed on the roof.
Hammer a copper roofing nail through the strip and into the roof every 1.2 m (4 feet). Install the nails an inch from the back of the copper strip, so that shingles cover the nails.
Align another copper strip next to the first one. Install the second strip using the same method as for the first strip.
Work lengthwise across the roof installing copper strips on both sides of the roof's ridge. You may need to cut more copper strips depending on the roof's size.
Remove existing moss with a solution of 1 litre (1 quart) of bleach, 4.5 litres (1 gallon) of water and 68 g (1/4 cup) of trisodium phosphate. Copper sheets are available at local roofing supply stores. You can substitute zinc-coated metal for the sheet copper. However, zinc may discolour roof shingles.
Use proper roof safety equipment to prevent falling off the roof. Do not access the roof in icy, windy or wet weather.