A concrete tile roof is often referred to as a “50-year roof”. They can last a very long time. But they are not maintenance free. Periodic maintenance needs to be performed to keep the roof in a sound and leak-free condition. Although many prospective homeowners become very concerned when roofing issues arise, most roofing issues are very common and simple to address. The more people know about concrete tile roofs the easier it is to allay fears and make intelligent and informed decisions.
Damaged Tiles
The most common cause for damage to concrete roof tiles is wind. The wind gets under the tiles causing them to shudder, shimmy, chip, and crack. Sometimes the wind can even move the tiles out of the proper position. Most of the roof tiles (field tiles) are secured with just a single nail, and when replaced, they are typically secured only with adhesive.
What most people fail to understand is that concrete tiles do very little (if anything) to keep moisture out of the home. In fact, they’re not water tight at all. Concrete tile roofs, like most roofs, are a system and the primary purpose of concrete tiles is to protect the underlayment. This underlayment can be felt or synthetic; however, by far the most used in our region is felt, which is located under the concrete tiles and above the roof decking. The felt is petroleum impregnated and repels water—Oil and water do not mix—Tiles do nothing to keep the water out of the structure, their purpose is to protect the felt.
Protecting the Felt
Without the concrete tiles installed over the felt the felt would be exposed to direct sunlight. Direct sunlight carries strong ultraviolet rays. UV rays cause the petroleum in the felt to evaporate. When the felt dries out from prolonged exposure to UV rays the felt then loses its ability to repel water and the potential for a leak is high. Concrete tiles protect the felt from the damaging ultraviolet rays and act as an insulator.
So, to recap:
-
- Cracked tiles are a common occurrence.
-
- Concrete tiles do not repel water
-
- Concrete tiles protect the felt.
-
- The felt provides the watertight integrity for the roof.
Roofing Pertaining to a Home Inspection
First you need to know that most homeowners never do the required recurring maintenance associated with a roof. It is extremely common for an inspector to find cracked or missing tiles or tiles out of proper position. This is fine and nothing to get wrapped around the axle over. Chances are this will not contribute to a water intrusion issue. But cracked or missing roof tiles are not an issue that should be ignored. If this issue arises at your inspection, then it is very prudent to ask the seller to perform the required routine maintenance to the roof.
It is extremely critical that this deferred maintenance be performed only by a licensed and qualified Roofing Contractor. It should never be performed by the homeowner or a Handyman Contractor. Many Handyman Contractors lack the expertise to properly address all roofing issues. When the work is accomplished by a licensed and qualified Roofing Contractor there is a much better chance that the work will be performed correctly.
Regardless of whatever warranty the Roofing Contractor states they will honor, here in the State of Nevada, statutory limits on contractor workmanship is four (4) years. It is extremely important that the prospective homebuyer is provided with a copy of the repair invoice so they may enjoy relevant statutory warranty benefits.
Repairs to be Performed
When a roofing contractor is retained, the contractor should be directed to review the entire roof and all associated components and corrected as needed to restore the roof to a normal, sound condition. If cracked roof tiles are found, then it is an indication that the homeowner has not properly maintained the roof. There are other issues that require routine maintenance on the roof.
The roof has penetrations installed. There are areas of the roof where vent pipes for plumbing, the furnace, the water heater, bathroom and laundry room fans penetrate the roof. These penetrations are sealed with mineral flashing. Mineral flashing is a “goopy” viscous product that is applied at the base of the penetrations. Mineral flashing is petroleum impregnated and repels water – just like felt. The mineral flashing is often exposed to direct ultraviolet rays from the sun. It needs to be renewed periodically. Painting the mineral flashing once it has dried will protect it from the ultraviolet rays of the sun and reduce the periodicity for this normal recurring maintenance issue.
When addressing cracked tiles, it is important to understand that unless a concrete tile is cracked more than 25% of the face of the tile then the tile does not require replacement; it can be repaired with cement epoxy. As a general rule, tiles with a chip that meets or exceeds 3 inches should be replaced as the chipped area may exceed the minimum head lap of the tile beneath it. This could expose the underlayment to sunlight, which will compromise it prematurely. If tile replacement is necessary, it’s important that the homebuyer understands that the contractor should attempt to match the color as closely as possible, but an exact match is often not possible. In fact, the Nevada State Contractors Board allows for up to 10% of the tiles to have differing colorations. So do not expect an exact match when the tiles are replaced.
Generally, most Roofing Contractors will charge upwards of $500 to perform the needed deferred maintenance; however, it they determine that the felt has been damaged then a section of the roof may need a “lift and re-lay” in order to replace the damaged felt and restore the roof to a sound condition. This can increase the cost of repairs considerably. It is important that the Roofing Contractor provides an assessment of any felt that has been exposed to ultraviolet rays..
