- Standard underlayment covers most of the roof area and is designed to shed water.
- Ice & water shield is a self-adhered membrane used in specific high-risk areas (and sometimes full coverage in certain designs).
A good roofing system often uses both: peel-and-stick where leaks are most likely, and synthetic/felt across the remaining roof.
Can you install shingles without underlayment?
It’s not recommended and often not code-compliant. Underlayment is part of the roof system and helps protect the deck if water gets under shingles.
Does underlayment stop leaks?
It helps reduce the chance of leaks reaching the deck, but it’s not a substitute for correct flashing, ventilation, and proper shingle installation.
What underlayment does to your roof
Even a well-installed roof can face extreme weather conditions in Maryland. Underlayment helps by:
- Backing up your shingles: If water gets under shingles due to wind, debris, or aging, underlayment helps keep it from reaching the deck.
- Protecting the roof deck: Wet decking can lead to rot, mold, and structural issues.
- Improving roof performance: Many modern underlayments improve tear resistance and reduce wrinkling, which helps the roof lay flatter.
- Meeting code and manufacturer requirements: Underlayment type and placement can affect warranty coverage.
Need roof underlayment installation in your area?
If you’re getting a roof replacement or you’re dealing with a leak that keeps coming back, underlayment is one of the first things a professional should evaluate. Here are some extra tips:
- Get a clear explanation of which underlayment type is being used
- Ask where peel-and-stick membrane will be installed (eaves, valleys, penetrations)
- Make sure the deck will be inspected and repaired as needed
Want a quote or a second opinion without worry about asking the right questions?Fifth Sun Roofing can inspect your roof system, explain your options in plain language, and recommend the right underlayment setup for your home. Click here: I want my free inspection today.
