Special Reports

Wichita's slab-house rules less strict

Wichita has fewer regulations in place to protect consumers who buy concrete-slab houses than several Kansas cities surveyed by The Eagle.

According to building officials in those cities, all have protections in place to avoid the kind of structural failures plaguing the Maple Shade subdivision in southeast Wichita.

Officials in several of those cities say that slab-foundation houses are a low-end thing of the past, giving way to higher-priced larger houses with basements.

Building codes other communities have in place include:

* Derby — Community development director Charlie Brown said the city empowers all of its building inspectors to require soil compaction testing on questionable soils.

Soil is tested for its compaction to make certain it will support the weight of a house and will limit shifting, which can crack foundations and pull apart walls.

* Newton — Slab-foundation houses are relatively rare in Newton, said Terry Williams, the former city planner who now works as a commercial building inspector.

However, when they're built the city requires construction on "undisturbed natural soil," Williams said.

Any house built on fill dirt must have footings "completely through the fill to undisturbed soil, or submit to a thorough engineering investigation of the fill," Williams said.

Newton requires either fiber mesh or steel-reinforced concrete for the slabs.

* Overland Park —"I don't think we've built a slab-on-grade house here in a decade," said city planning administrator Bill Ebel.

During a rapid growth spurt, most of Overland Park's new construction has been upscale, including basements.

But if someone did build a slab house, Tim Ryan, codes administrator at Overland Park, said the city would aggressively enforce soil studies and a firm requirement for steel-reinforced foundations.

"Our inspectors are trained to look at soil conditions," he said. "If they see any fill, they're ordered to stop the project and require the builder to get a geotechnical report on the soil conditions and a structural engineer to design the footings and the foundations based on the geotechnical information."

Overland Park requires college degrees and an engineering background to work as a building inspector, Ryan said.

* Park City — There are no soil-testing requirements on the books, and the city doesn't inspect slab foundations after they are poured, said Darrell Boger, Park City's director of code enforcement.

However, inspectors do require that all footings be poured on "virgin soil," not uncompacted fill, Boger said.

"If they're sitting on fill, that fill has to be compacted to a certain density, like 95 or 96 percent, to support the loads," Boger said.

City inspectors are allowed to visually inspect foundation digs to insure that kind of compaction, Boger said.

* Wellington — City building inspector Wes Bennett said Wellington doesn't have "a lot" of slab-foundation houses.

However, when slabs are built, the city requires that they be built "on undisturbed soil or approved structural fill," Bennett said.

All slabs are required in Wellington to have a "welded wire mesh" reinforcement, not the fiber used in Maple Shade. In addition, Bennett said slabs are required to have a plastic moisture vapor barrier underneath them.

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