Should I replace or repair my concrete tile roof?

Should I Replace or Repair My Concrete Tile Roof

Do you have problems with your tile roof?

Many homeowners are under the impression that their tile roof is supposed to last forever. This is not true!

The bucket in this attic is from a 21-year-old roof here in Southern California on a home that was built in 1989. For future reference, we will call this roof “A”. The homeowner placed this bucket here while he was inside his attic. He had to push the roof tiles up with his hands to get the bucket into position. The plywood and the underlayment below the tile had completely disintegrated and were completely gone. The plywood and tile underlayment had failed years earlier which puts the life on this roof at about 10-15 years before it failed.

Tract homes built in this country operate on a low bid basis and up until the last 5 years or so, tile roofs for the most part have had only one layer of underlayment installed below the roof tile. If a tile roof is installed properly per current manufacturer recommendations, this would provide approximately an 18-20 year life expectancy. In addition to a proper installation, it is important to regularly maintain your tile roof. Regular maintenance can avert or warn a homeowner to this type of situation. Roof “A” failed well before its expected life. This can happen when the roof is not installed properly to begin with.

Some of the reasons that roofs fail prematurely:

  • Improper pipe and vent flashings.
  • Stretching the roof tile. (Tile installed without proper headlap)
  • Flashing or counterflashings not installed correctly.
  • Broken tiles left unrepaired for years. This exposes the felt to the UV rays of the sun and can eventually allow moisture to enter below the roof tiles.
  • Improper installation of the underlayment.
  • Underlayment manufactured in countries outside the United States. These would save the contractors in some cases only $50.00 per house and provide in some cases only half the expected life.
  • Inadequate ventilation.

Here to the left is roof “B”. This is a 24 year old roof and a good example of what happens when there is improper flashing at the pipes and vents. The damage directly below the vent pipe is due to the fact that mortar was used to flash around the pipe onto the roof tile. Once the cement cracks, moisture enters below tile. In the past, manufacturers regarded mortar as an acceptable method of flashing a pipe. Since these methods did not work, secondary flashing installation requirements have been updated to require secondary soft metal flashings.

On this diagram of roof “B”, there was only a slight stain showing on the living room ceiling. Originally, the flashing at the chimney was not installed correctly. At first glance, it seemed as though a simple repair could solve the problem, however, a thorough inspection revealed slight indications of some possible issues. There was some very slight bubbling paint visible over the plywood eaves and that was about it. There were no exterior visible water stains, or obvious wood rot of any kind on this home. The homeowner was informed that the roof was beyond its serviceable life. Our first recommendation prior to any repairs was a complete reroof. This recommendation was in part because of the age of the underlayment, the pipe and vent flashings having been flashed with mortar, the interior leak, and the slight bubbling of the paint below the overhang on the eaves and gables.

The homeowner followed our advice to reroof completely reusing the existing tile. Below is a list of the additional work that was required due to dryrot found during the re-roofing process.

If the underlayment is suspected as the problem that is creating your roof leak, then reroofing is the correct solution. Whether or not new tile or existing tile is used is completely up to the individual, however, once the underlayment is not protecting the structure from moisture, the roof should be replaced.

The photo on the left is from roof “B”. This is a close-up of a portion of the roof underlayment that the roof tile rests on. You can see that the underlayment has deteriorated in this area and will allow moisture to enter the structure. Once any moisture enters below the roof tiles, for whatever reason, it will penetrate the underlayment and damage the structure now that the underlayment has failed. The cracking area of the underlayment shown above within the circle is due directly to the age of the underlayment. This cracking occurs as the asphalt based underlayment ages and the oils dissipate. The only way to fix this is to replace the underlayment. As in this example, this type of damage can remain unnoticed for years. Regular yearly maintenance and inspections are a cost effective, long-term solution for protecting your investment. Ask us about our maintenance programs.

This enlarged view of the same area of roof “B” is so that you can see more of the spots that the roof tiles rest on. As you can see here, this damage is not below every tile. Even though five out of these nine spots are bad, you can check ten other roof tiles and not see one instance of this type of damage. When a roof section is repaired, it is important to note if this type of damage is occurring. If this is occurring, then it is indicating that the roof is beyond its serviceable life. And regardless of these types of problems, the age of your roof should be a primary factor for considering replacement of the roof underlayment.

This ceiling is directly below the bucket shown in the attic of roof “A”. This is another example of how even though there is not a great deal of damage inside, the damage to the structure is severe. Another point to consider is that once the structural wood rafters and sheathing are exposed to moisture they are more prone to the infestation of termites.

This 2” x 4” section of rafter was removed from the eave of roof “B” straight down the roof from the small stain on the ceiling. This damage was completely unnoticed until a nail was driven into this blocking from an adjacent fascia board. This necessary wood replacement created a significant increase to the cost of the project.
We recommend that you have your home inspected for termites regularly, especially if you have any roof issues.
This underlayment on roof “A” is located on a portion of the roof completely away from any leaks that are showing up inside. The deterioration of the underlayment is quite evident. Even though there are no visible leaks from the interior of the home, the plywood and structure within the attic are becoming damaged. In this case, if repairs to the roof were isolated to the immediate area where the bucket was placed, damage would continue growing into other portions of the home. These types of observations and a regular maintenance program are how our experience as a professional full service roofing contractor can help to protect your investment.

As you can see through the examples provided above, it is important that your roof be inspected thoroughly and maintained regularly. When your roof is starting to show signs of failure, it is a good idea to replace the roof in its entirety and reduce the additional cost of wood damage that will only increase as the years go by.

Please call me directly, should you have any questions or would like to schedule a meeting at your property.

Yours in Service,


Shadowcrest Roofing Inc.
285 Pawnee St., Suite C
San Marcos, CA 92078
Michael V. Brito – President
Phone (760) 593-0300
Fax (760) 593-0327
Email – [email protected]
Lic# 926498

About Shadowcrest Roofing: We are a San Diego roofing company with over 40+ years of roofing and sheet metal roof experience. We service the commercial and residential sectors with some of San Diego’s premier general contractors and property owners. We utilize the latest in industry technologies and stay current with the roofing industry, drawing from a library of manufacturer’s information.