Architectural shingles, sometimes called dimensional or laminate shingles, are a popular choice for homeowners due to their durability and attractive look. When it comes to reroofing or “re-covering” your roof with architectural shingles, building codes generally have specific rules to ensure safety and proper installation. Most local codes limit the number of shingle layers to two; meaning you can typically install architectural shingles over one existing layer but not over two or more. This is because multiple layers add excessive weight and can affect the shingles’ ability to lay flat and shed water properly. To check if your roof is suitable for a re-cover, you can carefully inspect your attic with a flashlight to count the shingle layers visible at the roof’s edge or look for signs of unevenness. If the old shingles are too worn, damaged, or there are more than one existing layer, a full tear-off will likely be required to comply with code and maintain your warranty.
Before taking any steps yourself, it’s safe to do a visual examination from a ladder, looking for curling, cracking, or missing shingles and checking flashings around chimneys and vents. However, climbing on a roof can be risky—if you’re unsure or uncomfortable, call a professional roofer for a thorough evaluation. When discussing a re-cover with your contractor, ask if your local building department allows overlay work with architectural shingles and how they ensure compliance with both code and manufacturer warranty. You might also want to inquire about ventilation improvements or underlayment options, since proper airflow and moisture barriers can extend the life of your new roof. Being informed helps you avoid costly mistakes and ensures your roof performs well for many years.