Franklin County homeowners will pay on average about 2 percent more in property taxes next year based on appraisal estimates released July 17 by county Auditor Clarence Mingo.

Taxpayers can blame a booming housing market for the increase. Mingo's office concluded that home values rose 14 percent since property values were last updated three years ago.

"To the extent the double-digit increases are shocking to taxpayers, it's only because we lived previously with values increasing marginally or even decreasing," Mingo said.

"We expect the next three to six years to reflect more modest and more traditional growth."

Individual homeowners should receive their new appraisal estimates in late August. On July 17, Mingo released average increases by school district.

Over the past three years, home-value changes ranged from a low of 8.5 percent in the Dublin school district to a high of 29.9 percent in the Grandview Heights district, according to the auditor's figures.

Based on those figures, property taxes are expected to increase on average 1.3 percent in Dublin and 4.15 percent in Grandview Heights.

Grandview Heights homeowners will pay, on average, $100 more in taxes for each $100,000 in home value. Homeowners in most school districts will pay about $50 more a year in taxes for each $100,000 in home value.

Homeowners in the Licking Heights district will see taxes rise 10.5 percent -- or an additional $255 a year for each $100,000 in value -- largely because of a new 4.99-mill levy.

The Licking Heights school district includes part of Jefferson Township, which is in Franklin County.

"While the rise in value triggers a marginal increase in property taxes, the more substantive increase is always due to levies, which voters control," Mingo said.

State law limits the amount of new taxes that schools can collect because of a rise in property values, so a 10 percent increase in value, for example, does not lead to a 10 percent increase in property taxes.

Dave O'Neil, communications director for the auditor's office, pointed to House Bill 920, which became law in 1976. Basically, as property values increase, the effective millage on property taxes decreases.

O'Neil said cities like Dublin weathered the storm a little better than others in 2010 and 2011, when the housing market was weak.

"In Dublin, the market stayed pretty consistent and pretty solid," he said.

This is the county's first major reappraisal since 2011, although property values were updated in 2014.

Franklin County homeowners may challenge their values in special sessions from Sept. 5 through Sept. 28. The schedule of reviews should be posted later this summer at franklincountyauditor.com.

Homeowners also can challenge the values during annual board of review meetings in February and March.

Mingo said 60 percent of homeowners who challenged their bills in September during the last reappraisal received some change in their values.

"They often know things about their home that we don't know," he said.

After values are finalized in November, tax bills with the new figures will be mailed in December.

ThisWeek editor Scott Hummel contributed to this story.

jweiker@dispatch.com

@JimWeiker