Many historic Philadelphia rowhomes hide their gutters inside the front cornice. When these built-in gutters fail, water soaks the wood and runs down the brick. Timely box gutter repair protects both.
We see failing box gutters in Fairmount, Spring Garden and Northern Liberties, especially on homes with old tar patches over the liner.
This guide explains how box gutters work and how we restore them.
Why Box Gutters Fail
Box gutters are hidden, so problems often go unnoticed. As a result, damage spreads inside the cornice.
- Worn liners. Old metal or tar patches crack.
- Clogged outlets. Debris blocks the drop tube.
- Poor slope. Water sits in low spots.
- Rotted wood. Wet framing weakens the cornice.
What a Proper Box Gutter Repair Includes
We rebuild the gutter as a complete system.
- Removing old liner and patch material.
- Repairing rotted wood and adding slope where needed.
- Installing a new copper or membrane liner.
- Setting new outlet tubes and leader heads.
- Flashing the liner under the roof membrane.
The Copper Development Association publishes design details for built-in copper gutters.
Box Gutter Repair or Conversion to Hanging Gutters?
Repairing the box gutter is best when:
- The cornice is historic and visible.
- Framing is mostly sound.
- You want to keep the original look.
Conversion may be considered when:
- The cornice is beyond repair.
- Historic rules allow changes.
- Budget is limited.
Signs Your Box Gutter Needs Help
- Peeling paint on the cornice.
- Water stains on the front brick.
- Drips from the cornice bottom.
- Ceiling stains in front bedrooms.
These signs mean water is already inside the cornice.
Frequently Asked Questions
How long does a copper liner last? A well-installed copper liner can last 50 years or more.
Can a membrane liner be used? Yes. Membrane liners cost less and work well when properly installed.
Do historic districts allow repairs? Repairs that keep the look are usually approved.
How often should box gutters be cleaned? At least twice a year, especially after fall.
Schedule Box Gutter Repair in Philadelphia
Philadelphia Exterior Contractors restores cornices, gutters and brick facades. Explore our exterior services, read more on our exterior blog, or contact us for an inspection.
