Most Chicago two-flats, greystones, and mid-rises sit under flat roofs that quietly fail in summer heat. Here is how owners and managers inspect, maintain, and protect them before the next storm.
Walk down almost any residential block in Logan Square, Pilsen, or Rogers Park and you will see the same thing overhead: low-slope and flat roofs covering two-flats, greystones, and brick mid-rises. They are practical for Chicago's dense lots, but they hold water in ways pitched roofs never do, and our climate is brutal on them. A single roof membrane endures sub-zero January nights, freeze-thaw cycles that pry seams apart, and then July afternoons where the rooftop surface can climb past 150 degrees.
Summer is the right time to inspect because the roof is dry, safe to walk, and the warm membrane reveals blisters and soft spots you would never spot in winter. It is also your last clear window before the heavy August and September storm season. Catching a lifted seam in June costs a service call; catching it after water has reached a top-floor tenant's ceiling costs drywall, paint, and a very unhappy resident.
Begin from the ground and work up. From the alley or sidewalk, look for sagging rooflines, stained brick below the parapet, and water trails on the facade of your Lakeview or Andersonville building, all of which hint at roof or flashing failures above.
Once safely on the roof, walk the entire surface slowly. On a built-up or modified bitumen roof, look for alligatoring, bald spots where the gravel or coating has worn away, and bubbles or blisters in the membrane. On a single-ply rubber (EPDM) roof, check for shrinkage pulling the membrane tight at the edges and for seams that have opened. Press gently with your foot in suspect areas; a spongy, soft feel underfoot means water has already gotten into the insulation below. Photograph everything as you go so you can track how problem spots change from one inspection to the next.
The single most common cause of flat-roof failure in Chicago is simply blocked drainage. Flat roofs are designed to shed water quickly through interior drains, scuppers cut into the parapet, or downspouts, and when those clog, water has nowhere to go.
Clear every roof drain of leaves, cottonwood fluff, shingle grit, and the windblown trash that collects on a Wicker Park or Ravenswood rooftop. Make sure strainers and domes are in place over each drain so debris cannot wash in. Flush scuppers and confirm downspouts run free all the way to grade. Summer in Chicago brings sudden, violent downpours that can drop two inches of rain in an hour, and a roof that drains slowly during one of those storms will pond, overload, and leak. Fifteen minutes spent clearing a drain prevents thousands in interior damage.
Contact Lena Services INC at 773-939-4284 or [email protected]