Counter flashing (also called cap flashing) is a second layer of metal that overlaps the top of the base flashing at masonry, stucco or walls, shielding the joint from water. Repair means re-setting loose pieces, re-cutting mortar grooves or replacing rusted metal. It is a detail within flashing repair services in Folsom, CA that is often overlooked.
What counter flashing repair involves
Base flashing is bent to turn up a wall. Counter flashing is the piece that covers its upper edge, so water running down the wall cannot slip behind it. At a brick chimney, counter flashing is set into a groove cut into the mortar. At a stucco wall or parapet, it may be a surface-mounted or recessed piece sealed to the finish.
Because the counter flashing sits against masonry, it fails when mortar erodes, when metal rusts, or when sealant alone has held it in place. Repairs include re-pointing the groove, installing new pieces with proper laps and sealing only where movement is expected. It is closely tied to chimney flashing repair and apron flashing, which it often covers.
Common problems this repair solves
- Counter flashing pulled out of eroded mortar
- Metal rusted or lifted along the top edge
- Sealant used as the only attachment
- Pieces too short to lap the base flashing
- Stucco cracks above the metal letting water behind it
Signs you may need counter flashing repair
- Visible gaps between the metal and the wall
- Crumbling mortar at the groove above the flashing
- Rust streaks down the masonry
- Stains inside near the wall where the roof meets it
- Loose or rattling metal at a chimney or parapet
How the repair process works
- Inspect the joint. The provider examines the counter flashing, the base flashing beneath it and the wall material.
- Prepare the surface. Failed sealant and loose mortar are removed, and the groove or surface is cleaned.
- Install the metal. New counter flashing is set and lapped over the base flashing with fasteners and sealing where appropriate.
- Finish and check. Mortar or stucco is repaired and the joint is checked for water entry.
What a good repair achieves
- Protects the base flashing from direct water
- Stops water getting behind the wall joint
- Extends the life of the whole joint
Three ways counter flashing is attached to a wall
A reglet is a groove cut into the mortar joint or concrete, into which the top edge of the counter flashing is inserted and sealed. It is the traditional choice for brick and block, and it looks clean. Surface-mounted counter flashing is fastened to the face of the wall and sealed along the top edge, which is simple but depends on sealant staying intact. Recessed or built-in flashing is installed as the masonry goes up and is easiest to do during construction.
On an existing chimney or wall, the choice depends on the masonry's condition and the look. A roofer who proposes a reglet should check the mortar first. If the mortar is crumbling, the groove needs repair, or a surface-mounted option may be better.
Mortar matters: re-pointing and timing
Counter flashing repairs on brick often need mortar work: removing loose mortar, cutting the groove, setting the metal and re-filling the joint with a compatible mix. The wrong mortar, too hard or the wrong color, can damage soft historic bricks or look patched. Mortar also needs time and mild weather to cure, so a repair in very hot or freezing weather may need extra care.
If your quote does not mention the mortar at all, ask who will do it and what type will be used. Sometimes the roofer subcontracts the masonry work, and you should know who is responsible if it fails.
Counter flashing mistakes that cause repeat leaks
- Relying on caulk alone as the attachment
- Cutting the groove too shallow, so the metal pulls out
- Using pieces that are too short to overlap the base flashing
- Reusing rusted metal because it looks fine
- Skipping the end joints, where water often sneaks in
- Ignoring cracks in the masonry above the groove
For chimneys, counter flashing is one of four flashing layers. See chimney flashing repair for how the base, step, cricket and counter pieces work together.
Counter Flashing Repair in Folsom: local considerations
Brick and stucco chimneys and walls are common in Folsom, and counter flashing details differ between them. Historic homes in Historic Folsom often include older masonry that needs careful re-pointing so the new work matches. In newer areas like Empire Ranch, stucco-clad chimneys call for different attachment methods.
Not sure which flashing you have? Our local roof flashing repair page explains how the layers fit together, and a provider can identify them on site.
Cost considerations
Counter flashing repair cost depends on how many linear feet are involved, the masonry condition, whether mortar work is needed and access. Re-setting a few pieces is a minor job; reworking a long chimney or wall is bigger. Prices vary by job.
Ask whether masonry or stucco repair is included in the quote or handled separately.
When to call a professional
Call a professional if you see gaps or rust at the chimney or wall. Mortar work and metal fitting at height are specialized, and incorrect sealing can trap water behind the metal.
Counter Flashing Repair FAQs
What is the difference between counter flashing and base flashing?
Base flashing sits on the roof and turns up the wall. Counter flashing overlaps its top edge and shields it.
Is counter flashing the same as cap flashing?
The terms are often used interchangeably for the cover layer at walls and chimneys.
Can caulk replace counter flashing?
No. Caulk can supplement metal, but it should not be the only protection.