ROOFING RETROFITS

• By Robbin Rittner-Heir
• 02/01/05

It may be something as innocuous as that brown spot on the ceiling that’s starting to look a lot like the continent of Antarctica. Then again, it can be as blatant as the constant drip, drip, drip from the fluorescent light fixtures. Either way, the message is being delivered, loud and clear. Like it or not, your schools’ roofs may have problems that are in need of immediate attention.

Since so many schools in this country are two score and older, roofing problems can leave districts with a lot of leaky square footage and a substantial drain on building maintenance reserves. Staying on top of roofing maintenance can keep your district ahead of the repair curve and, potentially, keep you from facing additional costs from property damage caused by water seepage, as well as increased energy usage and thermal loss.

Follow That Leak

Just because you see evidence of water doesn’t mean finding the leak will be a slam dunk. Most often it shows up as a stain on the ceiling tile, and when you pop that tile, you’ll find that there’s some kind of leak up there, says Franklin Brown, planning director for the Ohio School Facilities Commission.

Often, it’s nothing more than water coming from some piping distribution system, such as restroom plumbing, sprinkler systems or roof drains rather than some actual breach in the roof system. In any case, it has to be checked to rule out any problems with the roof.

“Most roof leaks don’t occur out in the middle of the roof,” Brown says.“The place where you see leaks most frequently is where you have two parts of the building coming together or where you have the roof intersecting a wall or a parapet.”

The roofing system most common on older buildings is the flat membrane roof, created by layering asphalt- or coal tar-saturated material, often finished with a layer of loose gravel. The gravel, Brown says, helps to retain heat in the winter, while cooling the roof in warmer weather.

Texas rain and humidity are particular enemies to the school roofs in the Cypress-Fairbanks Independent School District, says Roy Sprague, senior director of Facilities Planning and Construction for the district located in suburban Houston. Temperature changes also take their toll.

Expansion and contraction of the traditional asphalt roof coating from prolonged exposure to heat and cold will cause it to form cracks in the surface or allow it to pull away at the edges. Often, water will get into and be channeled through the roof membrane.“It (water) doesn’t always come down through the ceiling at the same place it’s leaking up on the top,” Brown says.

Though increased heating or cooling costs may be taken as an indicator, thermal leaks can be harder to detect and usually require thermal imaging. These leaks generally occur when the insulation layer of the membrane roof system begins to break down, Brown explains.

“Especially with the amount of rain we get, the last thing we need is our roof drains clogging up and then potentially causing the water to back up on the roof and potentially causing some structural problems to the building.”

Other factors that can contribute to roofing damage and system failure are trash and debris that can clog roof drains, Sprague says. Fireworks, as well as other types of debris landing on the school’s roof, can eventually damage the roof. “The next thing you know, you’ve got holes in your (roof) membrane and water coming into your building,” Sprague says.

According to both Brown and Sprague, the first line of defense against system failure is a proactive approach to regular roof maintenance.

Staying on Top of Maintenance

Roofing consultants, both Sprague and Brown agree, should inspect the roofs on an annual basis. They do both visual checks and mechanical testing of the water tightness at joining points, flashings and roof membranes, and evaluate existing drainage outlets. Brown says that consultants also can do thermal imaging of the roof membranes to determine if and where there is energy The cost of engaging a roofing consultant generally is based on the size of the district and the number of buildings to be inspected; however, Sprague feels the cost is worth the expense because of the damage, repair costs and inconvenience to building occupants that can be averted. In general, school maintenance staffs are the ones initially charged with monitoring the condition of the schools’ roofs and, generally, are the people who are first told of any leaks within the buildings. Sprague says that in his district, maintenance crews check each school’s roof on a monthly basis for any evidence of leakage, so that minor repairs can be done in a timely manner.

Major repairs that can’t be done by the district’s maintenance staff are turned over either to the roofing company, if under warranty, or to a contractor. In the case of the Cypress-Fairbanks ISD, that contractor is chosen annually by competitive bid and is on standby, with roof repairs for the different roof systems in the district as part of the predetermined menu of services, Sprague says.

Brown comments that the more things located on the roof of a school, such as heating and cooling systems that may require regular access, the greater the likelihood of damage to the roof.

He adds that if these items require maintenance people to walk on the roof frequently, then specific walkways need to be created to those areas so they can be accessed without having to walk on the roof membranes.

Sometimes, however, the simple question must be answered. Do you repair or replace the roof?

Making Roof Decisions

Since school roofs aren’t installed as single units, there are a number of options when deciding whether to repair or replace roof membranes.

According to Brown, there are a number of methods to repair the roof membranes. One is to remove the stone from the affected section of roof, then install another membrane over the damaged one. If the insulation is going bad, additional insulation and another membrane can be installed.

Total water infiltration into the insulation means you’re not going to be able to use a quick fix, but will probably have to replace that section of roof, Brown says.

Determining when to go for complete replacement needs to take into consideration the original age of the roof system, the current age of the roof system, the condition of the roof since the last installation and whether or not it’s under warranty, Sprague says. “If you have a four-year-old building, you could have already replaced that roof one time.”

Brown says he looks at the long-term use of the building in question. If a roof system doesn’t have, at least, a 10-year life span, they will replace the entire roof.

The Cypress-Fairbanks district requires a 20-year warranty on all new roofs and, while initially more costly than having a lesser warranty, Sprague says, it tends to pay off. “I can tell you from past experience (in another district), we did have roof failure and we did have a 20-year roof warranty, and I was able to get six roofs replaced completely under warranty at no additional cost to the district, all because we had those warranties in place,” Sprague says.

He adds that it makes no sense to go to the major expense and trouble of getting a roof system that may only last five years. “Most good manufacturers out there will agree to provide you 20-year warranties. You just have to ask for it.”