roof layers

DIY: What Is Under Your Roofing Shingles?

DIY: What Is Under Your Roofing Shingles?

If you have ever worked on your own roof, you probably know what is under your shingles, If you have never repaired a roof or you just want to know what your roofing company is doing, the shingles are not the only component to a good roof.

Roof Decking

The first layer that you will find under your shingles is the decking. The decking is nailed to the framework of your roof. When you are repairing or replacing your roof you will need to make sure that this decking is in good shape. Look for discolorations in the decking which might show damage to the decking.

If you do find discoloration, check to see if there are any signs of rotting. If your decking is rotting it could give way to those walking on it while repairing the roof. It can also lead to water leakage. It is best to take out the damaged decking and replace it with new wood. When having your roof replaced professionally, your roofing company should replace these. Make sure you have a reputable roofer to make sure this is done right.

The decking is there so that there is something for the shingles to be nailed to. Rotting decking underneath the shingles can cause the nails to come loose. This can cause the shingles to blow off during severe weather.

Metal Drip Edge

A metal drip edge needs to be installed on the entire perimeter of your roof. The drip edge is installed in order to protect the roof decking under the shingle edges from getting wet. Without the drip edge, water will go under the shingle edges and cause water damage and rotting to the decking. Drip edges come in various colors to match the trim of your home.

Ice and Water Shield

Certain areas of your roof can be more susceptible to water damage due to ice dams or heavy wind-driven rain. These areas are typically roof valleys (where two sections of roof meet) and areas around chimneys, vents, dormers, skylights, etc.

Ice and water shield differs from roofing felt in that it is a rubberized type of membrane that is self-sticking to the roof decking. The material is also self-sealing around nails. This type of shield is vastly superior to the old standard of metal flashing. It pretty much creates a close to 100% seal for troubled areas.

Roof Underlayment

Now that all of the edges and trouble areas have been taken care of, you need a protective layer on the rest of the roof. This is typically a water-resistant felt or synthetic underlayment that will be rolled out and nailed to the entire roof. This is a protective layer that is directly under the shingles.

The traditional underlayment is a felt or tar paper. This usually is a rolled paper-like material that is saturated with asphalt to create a water barrier under the shingles. You don’t want this type of underlayment to get wet so it should be put down right before the shingles are installed. If it gets wet it will have a tendency to curl upon drying.

Synthetic underlayment is a newer type of underlayment that is woven from synthetic materials such as polypropylene or polyethylene. The synthetic underlayment is a great choice because it’s properties allow it to be better at roof protection than the felt types. It is lightweight and generally easier to install and is not as easy to tear as the felt paper is.synthetic roof underlayment


If you are planning to do repairs or replacement of your roof yourself, make sure you pay close attention to all of these items that are needed. All of the above items are needed in order for your roof to function properly in protecting your home. If you choose a local Texas roofer to take care of the work, make sure they are the ones that you can trust. You don’t want to cut corners when it comes to your roof.

Posted in Roofing, Uncategorized

Post a Comment