Roof valleys: Maintenance tips to avoid costly repairs and claim rejections

When it comes to roof maintenance, property owners often overlook one critical area, roof valleys. These are the V-shaped depressions where two sections of a roof meet, and they play a vital role in channelling rainwater off the roof and into the gutters. If neglected, roof valleys can become blocked or damaged, leading to costly repairs and insurance disputes. Here’s what every homeowner and property manager should know about maintaining roof valleys and preventing water damage.

1. The problem with leaves and debris

Leaves, seeds, and other debris can quickly accumulate in roof valleys, especially if overhanging trees are present. In my own situation, my neighbour has, what I call, a “helicopter tree” because its seeds spin down and clog the roof. When debris blocks the valley, water cannot flow properly and backs up. This leads to water seeping under roof tiles and causing leaks. Regular cleaning is essential, trees should be trimmed back from roofs annually and valleys should be monitored and cleaned regularly.

2. Understanding valley flashing

Underneath roof valleys lie the valley flashing, which is a piece of stainless steel with upturned edges to direct water flow. If leaves block the valley, water will overflow and seep beneath the tiles, damaging the ceiling below. Insurance claims for such damage can be denied in certain policies if it’s determined that the valley wasn’t properly maintained.

3. The role of gutters

Blocked gutters exacerbate roof valley issues. When water cannot drain away, it backs up and may overflow into the roof. Regularly cleaning gutters and ensuring they’re free of debris is crucial for preventing water damage.

It is also a lot cheaper to clean the gutters regularly than to replace them when they have rusted through.

4. Sheeted and concrete roofs

For sheeted roofs, debris can trap moisture, leading to rust and eventual leaks.

Flat concrete roofs pose their own challenges, as wrong screeding can create areas where water ponds instead of draining. If outlets become blocked, water levels can rise above the waterproofing and seep into the building.

Regular inspections and cleaning are key to preventing these issues.

5. Hail and roof valleys

During hailstorms, even clean valleys can become overwhelmed. Large hailstones can pile up, blocking water flow. In such cases, insurance companies are more likely to honour claims if the homeowner can prove their valleys were clean before the storm. Taking photos straight after a hailstorm to document the condition of the roof can be a lifesaver during claims processes.

6. Avoiding common mistakes

Some homeowners attempt to waterproof their roof valleys by sealing them. This can backfire, as it creates a bed for debris to accumulate, worsening blockages.

Instead, valleys should be cut open and kept free of obstructions. Valley flashing should also be inspected regularly to ensure it remains functional and free of rust.

7. Painting roof tiles

When painting roof tiles, avoid painting the front edges closed. Roof tiles are designed to channel water through grooves, and sealing these can cause water to flow over the edges and into the ceiling. Use spray painting techniques to maintain the tiles’ functionality. In the video clip below, I do demonstrate this in two diagrams.

8. Dealing with old or mismatched roof tiles

Older roofs may feature tiles that are no longer manufactured, making repairs tricky. Mixing different tile profiles can create gaps that lead to leaks. If significant repairs are needed, consider replacing an entire section of the roof with new tiles while reusing the old tiles on other areas. Companies specialising in salvaged building materials can also be a resource for finding matching tiles.

Conclusion

Proper maintenance of roof valleys is essential for avoiding costly repairs and ensuring that insurance claims are not denied. By keeping valleys and gutters clean, inspecting valley flashing, and avoiding common mistakes like waterproofing or mismatched tiles, homeowners can protect their roofs and their wallets. Regular inspections and proactive maintenance go a long way in safeguarding your property from water damage.