My husband and I will be replacing our asphalt shingles with Architectural ones. The old ones started curling after 5 years. The house is now 15 years old and the shingles are cumbling in certain areas. However, we do not have any leaks at this time and would like to replace the shingles before this happens. It's a modular type, ranch style home, and the original shingles may not have been installed properly. The ridge cap is only about 30 feet long and our house is 56 feet in length. Some other contributing factors may be that we live in the trees, we're in Delaware so humidity is a factor, and we have cathedral ceilings so there is no attic or proper ventilation. I've seen a lot of products that can be installed under the shingles to aid in ventilation, but they are for houses with attics. Is there a product that would aid in ventilation on our style house. Thank you!