The roof over your head

Heavy winter weather can wreak havoc on the roofs of older houses. (Photo courtesy Tom Daniel)

Last winter’s heavy snows and ice formed from melting snow caused homeowners a lot of concern about their roof foundations. The heavy snow and ice dams that built up on gutters and spouts created many emergency situations throughout the city.

In the worst cases roofs collapsed from the heavy weight. Roofing contractors were busy for months and in some cases are still working on jobs created by the severe weather. Weak foundations were especially vulnerable, creating added stress on the structures of the houses.

Joe and Vicky Smith of 8th St. S.E. had major roof leaking problems and significant wood decay in the roof foundation over a period of years. The winter of 2010 convinced them it was time to take serious action. According to Joe, “The old roof had sagged over the last century and created an area where rainwater collected. Under this area, I could see water stains on the rafters and joists in the attic and decayed wood where the rafters sagged. The insulation was wet and we had to deal with leaks in two bedrooms. I knew that another bad winter would only make the damage worse, possibly even creating a dangerous situation.”

They had to decide what to do with the rotten wood and what type of new roof was best for them. Their existing roof was old and in disrepair. It was constructed of membrane above an old slag roof (gravel and tar). There were two roofs that had to be replaced, which is not unusual on Capitol Hill homes. While new roofs constructed of modified bitumen or EPDM (aka “rubber” roof) were fine and came with long-term guarantees from the manufacturers, they chose to have their existing old membrane and slag roofs removed and replaced with three new copper roofs covering the entire structure of their home.

About half of the roofs’ total surfaces required new sheets of plywood as well. The new wood to support the roof foundation would calm the concerns previously experienced by the Smiths.

“This was a long-term investment in our home that was consistent with our long term outlook,” Vicky said.

Copper roofs are fire- and spark-resistant and resistant to hail and wind. A copper roof properly installed will last as many as 100 years and requires little maintenance. They had also considered a tin or terne metal roof. These roofs are currently composed of a fairly equal blend of tin and zinc. Terne is used to coat sheet steel to inhibit corrosion. Terne metal must be painted initially and periodically thereafter but can last 50 years or more.

Finally, the gutters and spouts on the home were older aluminum and the decision was made to install new copper gutters and spouts.

“We chose copper gutters and downspouts for their aesthetic appeal and harmony with the roof materials. As a sailor, I also knew that mixing dissimilar materials such as copper and aluminum causes galvanic corrosion,” said Joe.

This mixing accelerates the corrosion process.

The Smiths’ roofing experience is a similar one for many homeowners with older flat or low slope roofs. Some of these older homes have sagging roofs, decaying roof foundations and leaks.

The key is to seek guidance on how to correct a roof foundation problem and what the options are to replace your roof. That is especially true when considering the upcoming winter season.

Tom Daniel is owner and general manager of R. Thomas Daniel Roofing and specializes in working on flat and low slope roofs on Capitol Hill, Georgetown, Dupont Circle and throughout D.C. Reach him at 202-569-1080, tom@rthomasdanielroofing.com or www.rthomasdanielroofing.com.