Slate and synthetic slate reroofing in Chevy Chase DC (20015)

A house built on Morrison Street in 1925 may still have its first slate, a second asphalt roof from the 1990s or a third roof installed last decade. The age of the house does not tell you much. What we look at is the material, the condition of the fasteners and the state of the flashing, because each wears on its own clock.

Pennsylvania and Vermont slate can last a century or more. Soft slate from other quarries delaminates sooner, flaking in layers you can see from a ladder. Asphalt laid in the 1990s is often near its end now, with curled tabs and bald spots on the south slopes. A roof inspection from a ladder and the attic tells you which group your house is in.

Flashing is usually the first thing to go regardless of roof material. Original copper on the oldest houses holds up well, but galvanized steel valleys and lead-coated chimney aprons from mid-century repairs rust or split. On Tudor houses with steep intersecting gables, a single failed valley can rot a section of decking while the slopes on either side look perfect. We check every valley from above and look for dark staining on the rafters below it in the attic.

We write down what we find slope by slope, with photos, so you can plan the work over a few seasons instead of all at once.

If the slate itself is sound and only a scattering of pieces have slipped, repair wins. We replace broken slates with matching salvaged stock, hang them on copper hooks and rebuild failing valleys and chimney flashing in copper. That work often costs a fraction of a new roof and leaves the original look intact.

When a large share of the slate is soft or crumbling, replacing it with new natural slate keeps the house authentic, but the cost is high. Synthetic slate made from polymer or rubber composite looks close from the street, weighs much less and costs less to install. It does not last as long as good stone, and that tradeoff is worth weighing before you choose.

Chevy Chase DC is not a designated historic district, so the choice is yours, with a standard DOB permit for a full replacement.

Large oaks and tulip poplars shade most lots between Western Avenue and Rock Creek Park. Shade keeps north slopes wet, and moss grows in the gaps between slates. The heavier problem is leaf load: half-round copper and aluminum gutters fill quickly, and overflowing water rots fascia and soaks foundation plantings.

We clean and reslope gutters during repair visits and recommend leaf guards where the tree cover is heaviest. Copper half-rounds on slate houses get soldered joints and new hangers rather than caulk.

Most houses have a driveway or side yard, so a dumpster can sit off the street. We protect the driveway with plywood under the container and cover plantings below the eaves. Slate tear-offs are heavy, so we sort reusable pieces from debris on the roof and lower them in buckets instead of chuting them.