The Tonganoxie school board on Monday unanimously approved a call for a bond issue not to exceed $27.2 million for a kindergarten through fifth-grade elementary school. State aid would account for 34 percent of the cost, or roughly $9.2 million, so taxpayers would be looking at paying about $18 million if the bond issue were to successfully pass.

HTK Architects presented $27.2 million and $25.9 million options, with the first plan accounting for 1,200 students and the second 1,000 students. The lower-priced plan had eight fewer classrooms, but would allow for expansion in the future.

Mark Franzen with HTK said at Monday’s meeting that if the bond were to successfully pass, a tentative opening date for the school would be August 2015. Enrollment projections would put the school at full capacity of 1,000 for six grade levels at that time with the lower-priced plan.

Franzen said he thought adding on in the future would carry more costs in the long run, such as additional engineering costs for a separate project.

“It’s never going to be any cheaper than it is now probably,” Franzen said.

Preliminary estimates put the 1,200-student building at 130,000 square feet.

Roger Edgar with George K. Baum and Associates presented the board with the average estimated tax impact on homeowners. For the $27.2 million option, a homeowner with a house valued at $150,000 would pay $201.60 in taxes per year or $16.80 per month. The $25.9 million option would have carried a tax impact of roughly $192 or $16 per month on the same home.

Board member Dan Hopkins said he favored the $27.2 million scenario.

“The 1,200-student option is best stewardship of taxpayers’ money and accommodate what our district needs for the students,” he said. “It’s tough making decisions knowing where the economy is right now. But the shape the old building is in, we’re in need, not want.”

The elementary school’s enrollment was 715 students for the 2011-12 school year. Ideal capacity is about 615. The district is looking to make the current elementary school a mixed-use building if a new school were built. Some potential uses: overflow classrooms for future growth needs in the district, shared space with City Hall, possible library needs, a community center, board of education needs, district special needs cooperative, parks and recreation, possible community college classrooms or virtual school.

The middle school currently houses grades five through eight, but it would be a sixth-through-eighth school if a new elementary school were built. USD 464 Superintendent Randy Weseman said the new building would be “schools within a school,” with grades kindergarten through second and third through fifth having separate wings. Preliminary designs have the separate wings sharing resources such as a kitchen, library and gymnasium, but with separate cafeteria areas.