I wanted to share with you about a repair we made for one of our Angie''s List customers in Prospect, Ky. Mr. Lyon called and asked us about repairing his leaking valley. He was concerned about how the repair would look because the valley was on the front of his house. We arrived and first went inside the house to see where the water had leaked through the valley and stained the ceiling. We then inspected the roof. The shingles (tabs) were starting to curl at their edges indicating it would be time for a new roof soon.
We removed the valley shingles and noticed a couple of issues. One, there was no additional protection in the valley to protect it from leaking. It is extremely important to provide added protection to the weak parts of the roofing system. Anywhere two roof lines meet, all projections through the roof and where a roof line stops at a wall are weak areas and a source of potential leaks. Years ago roofing companies would use metal in the valleys then felt paper then shingle over the valley. Nowadays there are better products on the market to address those issues. The best product we have found is Owens Corning WeatherLock which is a butyl rubber adhesive system. We installed WeatherLock which is a fantastic product, self adhesive and nearly indestructible once it is installed. It is 3'' wide, self adhesive and is installed right in the middle of the valley. If water does get through the shingles somehow the water would be redirected down the valley and away from the house. As long as I have used this product I have not had any problems with a leaking valley.
Two, we found the gutter guards (gutter protection) had been installed wrong. Let me say first of all I am not a fan of gutter guards that are designed to slide under a shingle. Many problems can occur during installation and they could be installed wrong. Which you may not be aware of for years to come. The protection systems that slide beneath the shingle break the sealing strip that seals the shingle to the course beneath. It will NOT reseal as well once the seal has been broken. So, wind damage can occur because of improper installation. I would recommend gutter protection that does not require infringing upon the roofing products.
The valley is now repaired but it is not pretty because the existing shingles had faded tremendously over time. In addition shingles made at different times will have slight variations. But mainly fading is the problem. Repairs will always be noticeable. If someone tells you otherwise RUN.