Remodeling an Older Brick Home in Utah: Earthquake Risk and Retrofits

Many older Utah homes are built of unreinforced brick, stone or block. The state says these buildings can be brittle and suffer damage or collapse in moderate to large earthquakes. If you plan to open walls or change the structure of an older brick home, ask a structural engineer about seismic upgrades before the design is final.

Why it matters on the Wasatch Front

The state estimates a 57% probability that the Wasatch Front will have at least one magnitude 6.0 or larger earthquake in the next 50 years. Most of Utah's unreinforced and lightly reinforced masonry buildings were built before 1975. Utah codes were updated in the 1970s to outlaw new unreinforced masonry construction, but thousands of these buildings remain.

Signs your home may be unreinforced masonry

• The home is brick and was built before 1975.
• Rows of bricks are turned endways every five to six rows.
• Windows are deeply recessed in the walls.
• Rows of bolts appear on the exterior walls.

What a retrofit can focus on

FEMA's case study of Salt Lake City's Fix the Bricks program says it emphasizes strengthening the roof-to-wall connection. That helps the walls and roof support each other against collapse. The case study notes this work was often done from the interior, where it has little visual impact. The right scope for your home comes from a structural engineer.

Plan the remodel around it

1. Ask whether your remodel already opens walls or ceilings where a roof-to-wall connection could be reached.
2. Have a structural engineer review the house before the design is final.
3. Secure the water heater to the wall studs and run flexible gas lines to gas appliances, as the state recommends.
4. Confirm the permit path with your city. Salt Lake City requires permits to alter, repair or improve a building.

Historic districts in Salt Lake City

In a Salt Lake City local historic district, exterior work other than paint color and minor maintenance needs a Certificate of Appropriateness before work starts. Interior work does not. Unpainted masonry in these districts cannot be painted, because paint can trap moisture and damage the brick.