Slate valley and chimney repair in Shepherd Park (20012)

On the flower-named streets west of 16th Street, like Holly and Juniper, the original slate often stayed on the street-facing slopes while an earlier owner put asphalt on the rear once the back slate wore out. Sometimes a dormer or a rear addition got shingles from day one. The roof works, but the joint where the two materials meet, usually at a hip or valley, leaks long before either surface does.

We rebuild those transitions with a proper metal valley or hip flashing that runs under the slate on one side and over an ice barrier beneath the shingles on the other. On the slate side, pieces come out and go back by hand on copper nails or hooks. It's careful work but not a huge job, and it usually ends a leak that has been smeared with roof cement for years.

If you'd rather have one material across the whole house, we can price new slate for the rear or a full shingle roof that settles the question. Both are fair choices, and the cost gap between them is wide.

Houses here often have a broad brick chimney on the end wall and a second, narrower stack for the furnace. Both have been through many decades of freeze and thaw. Spalled brick, open mortar joints and cracked crowns let water soak into the masonry, and it shows up as a stain beside the chimney even when the flashing is fine.

We start at the top and work down. A cracked mortar crown gets replaced with a poured crown that overhangs the brick, loose courses get relaid and open joints get repointed. When the leak really is at the roof line, we cut a reglet, set new counter flashing and tie it to step flashing under the slate or shingles. The chimney repair page covers stacks that need rebuilding above the roof.

On a typical visit, we check these points:

• Crown cracks and missing mortar wash
• Loose or spalled brick in the top courses
• Counter flashing pulled out of its mortar joint
• A rusted or missing cap and screen
• Unused flues that let rain fall straight down

The blocks near Rock Creek Park and the old Walter Reed campus sit under some of the biggest oaks in upper Northwest. Leaves and acorns fill gutters quickly, and a downspout that clogs at the elbow sends water over the front edge and into window wells. On houses with copper or galvanized half-rounds, we clean, flush and repitch the gutters before winter.

Overhanging limbs also scrape slate in the wind and drop debris that holds moisture in valleys. We point out branches worth trimming while we're on the roof, and our gutter cleaning visits include a look down every valley.

Shepherd Park is outside DC's designated historic districts, so repairs in kind need no preservation approval, and full replacements follow a normal DC Department of Buildings permit that we file. Lots are roomy by city standards, with driveways or rear alleys on many blocks, so a dumpster and a lift can usually sit off the street. On 16th Street itself, we time deliveries around rush hour and keep the sidewalk clear.

Homeowners on the Maryland side of Eastern Avenue sometimes ask whether we cross the line. We do, and the same roofers handle Silver Spring houses just north of the border.