While moss on the roof might not look very attractive, it isn’t just about curb appeal. Moss can significantly harm a roofing system, shortening its lifespan, damaging shingles, and making it prone to leaks. If it’s not dealt with in a timely manner, the consequences can be costly and extensive. This brief guide with tell your everything you need to know about roof moss.
Consequences of Moss Growth
Moss is like a green sponge, soaking up moisture and retaining it. Moss growth can create of number of problems for your roof ranging from a DIY fix to a roof replacement by a roofing contractor. The following are some of the consequences of moss growing on a roof if left untreated:
- Trapped moisture leading to wood rot
- Shingles shifting, leaving gaps as moss growth spreads
- Moisture retention
- Deterioration of roofing tiles as moisture wears away protective finishes
- Structural damage
- Stress from added weight (water is heavy)
- If moss gets into the gutters, can stop water flowing through the gutter channels, forming clogs and trapping debris
- Insects and pests looking for access to a warm place to nest in winter
Signs to Look For
By the time you see moss on the roof, it has taken hold. When moss becomes visible to the eye, you are seeing the top layers and not the system of rhizoids (thin hair-like roots) that allow the moss to spread and grow. However, there are signs you can look for:
- The appearance of pale green “shadows” or patches
- Discolourization caused by barely visible moss growth
- Stains caused by leaks or excess moisture
- Pooling water – moss impedes the flow of runoff from the roof into the gutters
- Spikes in your energy bills – moss reduces the functionality of a roof
Roof Moss Removal
If moss is already growing on your roof, it’s important that it is removed and you take steps to prevent it from coming back. Tips for removing moss from the roof include:
- When the area of roof moss is small or manageable, it can be removed with homemade cleaning solutions
- Use methods that kill the moss but won’t harm roofing shingles
- Use roof-safe cleaning products
- Don’t use a pressure washer – it could further damage shingles
- Select tools such as bristle brushes, scrapers, and long-handled brooms that will be gentle on roofing tiles
Call a professional roofer when:
- Moss growth is extensive
- The roof is steep
- The roof is complex
- There might be other safety or health concerns
- Roofing materials like concrete, slate, and clay that could be damaged by standard cleaning methods
Moss Growth Prevention
Moss growing on the roof and in your gutters are a threat to your home’s exterior. The best way to deal with roof moss growth is prevention. Ways to prevent moss from attacking your roof include:
- Clean the gutters and downspouts regularly
- Install zinc or copper stripes (discourages moss growth)
- Trim back tree limbs – moss likes damp, shady areas
- Perform regular roof maintenance
- Don’t allow debris to accumulate on roofing shingles
- Hire a professional roofing contractor for major repairs
- Conduct homeowner roof inspections every year and after significant storms
- Get a professional roof inspection at least every two years
If moss is growing on your roof, don’t ignore it. It might seem harmless – green and lush – but it doesn’t stay that way. Remove it as soon as possible after discovering patches of moss. Once it’s gone, do regular home maintenance to keep your roof healthy.
