What does a gap at the frieze board above brick mean?

Reviewed by Preston, Oklahoma foundation repair consultant · Updated 2026-10-14

In short: A gap opening between the top of the brick and the frieze board under the eaves, or at exterior trim corners, often means the foundation edge carrying the brick has dropped. On Oklahoma's expansive clay, this is commonly tied to soil drying and shrinking at the perimeter. A gap that is wider at one corner and grows in late summer points that way.

How does the gap form?

On a brick home, the brick veneer is a single layer of brick standing on the outer ledge of the foundation, while the roof, soffit and frieze board are attached to the wood framing. The frieze board covers the joint where the top of the brick meets the framing. When the foundation edge settles, the brick goes down with it, but the roof and trim stay where they are, so a gap opens under the frieze board. The gap is usually widest above the corner or section that dropped the most.

What is edge drop?

This site links the sign to perimeter drying settlement (edge drop). Expansive clay shrinks as it dries ². Engineering guidance on expansive soil notes that lack of watering during drought, which dries out the clay, can be more damaging than overwatering, and that tree roots extending under a foundation can cause shrinkage and settlement ⁴. Texas monitoring found that slabs on expansive clay settled through the growing season, that drought made it worse, and that winter brought partial recovery ³.

In Oklahoma, more than 75% of the state has bedrock that can produce expansive soils ⁵. See shrink-swell and active zone and drought and wet cycles.

What signs usually come with it?

• Stair-step brick cracks wider at the top on the same wall.
• Brick separating from window or door frames.
• Soil pulled away from the foundation in dry weather.
• Cracks around interior doors and windows on that side; on shrinkable clay, cracks typically need about 5 to 10 millimeters of movement to appear ⁶.

Home inspection standards list brick cracks and out-of-square door frames among signs of possible foundation movement to report ¹.

When might it not be the foundation?

A gap at trim does not always come from the foundation. Signs pointing away from the foundation include a gap that is even along a whole wall, no cracking in the brick below, and no matching interior signs. Signs pointing toward the foundation include a gap that tapers, wider at one corner, plus brick cracks and sticking openings on the same side.

How do you document it?

1. Measure the gap at evenly spaced points along each wall, and at every corner.
2. Photograph each point with a ruler in view.
3. Note which corner has the widest gap and check the brick below it for cracks.
4. Repeat through a summer and a winter; monitoring of slabs on expansive clay found settlement through the growing season and partial recovery in winter ³.
5. Add the corners to an elevation survey.

What are the next steps?

Compare with the distress pattern library and the symptom matrix.

Related

• Perimeter drying settlement (edge drop)
• Stair-step brick crack wider at top
• Brick separating from window or door frame
• Cracks that open and close seasonally
• Root barriers and moisture control