The owners of one of the last undeveloped classic brick warehouses that once defined the southern edge of downtown Des Moines plans to convert it into premier office space for a yet-to-be identified tenant. 

A development team led by Tim Rypma purchased the four-story Carpenter Paper building at 106 S.W. Seventh St. and the neighboring Lortex building, 113 S.W. Eighth St., in May from EMC Insurance Cos. The company announced earlier this year it was selling four downtown properties its employees no longer use.

EMC last used Carpenter Paper, built in 1918 for the wholesale paper company, as document storage space. It also used as storage the 1970s Lortex building, which Rypma hopes to convert into a restaurant or tavern in a second phase of development.

"It's a great piece of real estate," he told the Des Moines Register. 

He plans a historic renovation of the Carpenter Paper warehouse that includes restoring and tuckpointing the original brick exterior, exposing closed-off windows and removing corrugated steel paneling on the north facade. The heavy timber beams inside will remain exposed. 

He also plans a balcony or other feature on the east side to highlight the original third-floor entrance: The Carpenter Paper warehouse abutted the former Southwest Seventh Street Viaduct, from which workers entered the building. The viaduct, which crossed over multiple railroad tracks, was demolished in the late 1990s. 

Several other brick warehouses downtown already have been converted into commercial and mixed-use buildings, including the nearby Rocket Transfer Lofts and the Harbach Lofts. Ryan Moffatt, Des Moines economic development coordinator, told the Urban Design Review Board on Tuesday that Carpenter Paper is one of the last remaining to be converted into another use. 

Carpenter and Lortex were once part of a warehousing and industrial area on the south side of downtown, adjacent to the rail lines. With Carpenter Paper facing the last operating rail line through downtown, the renovation will be "a nod to the industrial heritage of the area," Moffatt said.

Des Moines also is hopeful the renovation will encourage companies that own massive, surface parking lots west of Carpenter Paper along Martin Luther King Jr. Parkway to sell them for redevelopment, said Moffatt, who called the area a "dead zone." A preliminary draft of a long-term master plan for downtown Des Moines also calls for new uses in the lots, which are now largely empty as companies allow employees to work from home during the COVID-19 pandemic. 

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"We're hopeful when this project comes about ... perhaps this can really spur some momentum, trying to get some of the other blocks developed," Moffatt said. 

Rypma, who specializes in historic rehabs, said he purchased the buildings for their proximity to burgeoning areas downtown, including mixed-use developments Grays Station, Grays Landing and the Market District, and plans for a Des Moines United Soccer League stadium. 

"That corridor has a lot going on ... so it’s a great piece of real estate that will hopefully evolve into something someday," he said. 

The Des Moines City Council in May voted on terms of a preliminary development agreement with Rypma, allocating $8.15 million in tax increment financing for work on both the Carpenter Paper and Lortex buildings. Rypma expects to invest $24.3 million. 

He said he hopes to start construction in the fall, but will wait until he finds a tenant. 

Des Moines has asked the development team to extend the sidewalk on the north side of Martin Luther King Jr. Parkway, which currently ends at Southwest Sixth Street. Moffatt said the goal is to have it eventually reach Southwest 14th Street when the parking lots become available for development. 

EMC still has listed for sale the 21-story HUB Tower, 699 Walnut St., and the west side of the Kaleidoscope at the Hub, 555 Walnut St. 

Kim Norvell covers growth and development for the Register. Reach her at knorvell@dmreg.com or 515-284-8259. Follow her on Twitter @KimNorvellDMR.