Install self-stick underlayment in areas exactly where codes require it. Frequently referred to as “ice-and-drinking water” underlayment, it helps prevent h2o that seeps under the shingles from detrimental the decking as it sticks into the roof decking to seal out water. In addition, it seals all-around nails and retains h2o https://learntomore.com/5-contractors-recommended-in-hinsdale-il-top-experts-for-your-project/