Is your roof built to last?
3 Common Installation Problems and How to Fix Them
When asked what you feel grateful for, you might mention your friends, family, and the roof over your head. However, though you count your roof among your blessings, you might not be treating it with the care it deserves! In this series of blog posts, we will discuss common issues with roof construction and care, helping you extend your roof’s lifespan for years to come. We focus on asphalt shingle roofs, because they are the most common roof material due to low cost and wide availability.
A few components of the original roof installation will impact its function and longevity, including shingle type and placement, penetrations (like chimneys and skylights), and flashing.

1. Shingle Type. There are two main types of asphalt shingles: fiberglass and organic. Fiberglass shingles are waterproof, lightweight, and fire-resistant. Less commonly used are organic shingles, made with wood chips and other recycled materials. Organic shingles cost less than fiberglass, but are more prone to moisture and saturation, and therefore don’t last as long.
2. Shingle placement. Shingle rows must be offset, or “staggered,” in order to prevent leaking. If they aren’t staggered, water can seep into the seams instead of running down the roof, causing deterioration, moss, and leaks. Also, multi-layered roofing, also called “overlaying,” or when a new roof layer is installed over an old one, can shorten the roof’s lifespan. Most areas have regulations that prohibit more than two roof layers; consult local building codes to clarify.

Though it may cut costs initially to install a new roof layer without removing the previous one, it often leads to more issues down the line. For instance, it makes the roof heavier, which can cause cracking and damage to the interior ceilings. Heat and moisture trapped between layers can impede attic ventilation below. Also, “telegraphing” can occur: this refers to when the newer roof conforms to the older roof, making it uneven and impeding drainage. Finally, multiple layers are generally not warranted by shingle manufacturers, and often only the top layer can be insured, which makes repair even more costly. Multi-layered roofs save money initially, but aren’t worth the risks they pose.
3. Penetrations, like chimneys and skylights, also affect the roof’s life expectancy. Though they serve important functions, like venting smoke or providing light, these penetrations are susceptible to leaking because they pierce the roof barrier. If these joints are protected with a non-permanent sealant, like caulk, which is prone to cracking and failing, chances of leaking are increased. Proper flashing, which is a waterproof barrier installed at these joints, will prolong the roof’s lifespan and secure chimneys and other fixtures against movement.
Keep your home repair costs from going through the roof by addressing problems with the original installation early. Read on for maintenance tips and environmental info to further extend the lifespan of the roof over your head!

