The Sun-Sentinel reports that Lake County School Board members could decide Monday to seek a nearly 150 percent increase in the fees builders must pay to help build classrooms in the county, which has become the fastest growing section of the Central Florida housing market.

The proposal could make Lake’s school impact fees the highest in the state - $17,513 for most new residential development. That is about $10,000 more than builders in Lake pay to construct a single-family home, and $7,532 more than Florida’s current top school impact fee (in Osceola County).

Earlier this month, the Orange County School Board agreed to pursue upping the school impact fee to a minimum of $9,696 for a single-family home, a 38.5 percent hike.

That would put Orange just below Osceola’s $9,981.

Lake’s School Board is scheduled during its Monday night meeting to vote on rates that would dwarf Osceola’s and the one proposed for Orange. While the new figures are daunting, Chairman Larry Metz said the increase is needed.

“It’s going to raise eyebrows,” Metz said. “But we are experiencing that type of surge in the cost that we’re paying [to build schools].”

Meanwhile, Florida home builders have (not surprisingly) balked at the numbers that are being discussed, saying that such a dramatic increase likely will inflate the real estate market and turn away first-time buyers.

“It’s way too high,” said Jean Kaminski, executive director of the Home Builders Association of Lake County. “We already have a terrible affordable housing crisis in Lake County. And it’s no longer just the very low-income. It’s the working people that can no longer afford housing.”

While home builders cite soaring construction costs as having an adverse impact on their business, school planners say the district also must keep up with those same building costs.

“The simple and bottom line answer is … construction costs for schools, just as they have for homes, have increased substantially,” said Harry Fix, the Lake district’s director of growth planning.

Now the challenge is building enough classrooms to accommodate an expanding student population. So far this year, two-thirds of district schools are crowded. During the next five years, the district plans to expand at least 12 schools and open a dozen new ones.

At the current rate, impact fees are expected to make up 12 percent of the district’s $700 million projected five-year building program.

Impact fees are calculated based on factors such as classroom capacity, the average number of children in a household and the area’s cost per student. By 2010, officials predict nearly 47,000 students will attend Lake public schools.

Lake’s school impact fee was last raised in 2004 when the County Commission doubled the rate to $7,055 for new single-family homes. Commissioners then rejected the School Board’s request to charge Florida real estate developers an extra $3,000 for the interest paid by the school district for borrowing money.

This time, the proposed fee again includes that cost of borrowing. Builders would be asked to pay about $5,000 for each new home to cover it. But the School Board isn’t sure how the County Commission will respond.

In addition to the proposed $17,513 fee for single-family homes, the firm suggested a $10,574 fee for multi-family homes and a $6,198 fee for each new mobile home - potentially hitting people already pinched by Florida home mortgage payments.

Some doubt the district will see the money it envisions.

If the increase is approved, more developers likely would want to build in age-restricted subdivisions and communities where they are exempt from the fee.

Builders’ possible shift toward that market coupled with a slowdown in home sales may hurt expected income - a grim prospect for a populace already struggling with staggeringly high Florida mortgage costs.