Tansey Development is Riverheath's owner while Engberg Anderson Architects is the firm responsible for designing The Willow. Core 4 Engineering is the structural engineering firm which was chosen for the project.
Spancrete provided the precast elements and erected DELTABEAM®, the structural solution chosen by Engberg Anderson Architects to meet the height restriction challenge they were faced with on part of the podium construction project.
“Being a type IIIA construction above the plinth building meant that we were faced with a 75- foot height restriction from grade at the river side to the sixth-floor finished elevation. Deltabeam was used in order to achieve maximum head clearance in areas of the building where headroom would have been very tight otherwise” says Felipe Ornelas, Principal at Engberg Anderson Architects’ Milwaukee office in Wisconsin.
The biggest challenge with podium construction is to transfer the weight from all the residential floors above through a transfer slab into the columns of the lower levels of the building.
In the case of Riverheath, having to support 5 levels of wood construction meant the load applied on the transfer slab was massive.
"In some locations, DELTABEAM® had to withstand a load of over 775,000 lbs while having a clear span totaling 34 feet", says Abdelhamid Smair, Project Manager for Peikko USA.
Having a beam which could stay exposed without requiring any additional fireproofing was also appealing for Engberg Anderson Architects.
“Another advantage of using DELTABEAM® is that it comes with integrated fire resistance which eliminated the need for any additional fire proofing onsite”, says Felipe Ornelas, Principal at Engberg Anderson Architects’ Milwaukee office in Wisconsin.
DELTABEAM® has been tested by Underwriters laboratories (UL) and is listed for up to 4 hours without requiring any kind of additional fireproofing whatsoever. The reinforcement inside the concreted beam assures that beam capacity remains sufficient in case of fire.
DELTABEAM® is also appreciated for the design flexibility it provides by allowing large open spaces while eliminating headroom issues.
Reid C Spiering, Structural Project Manager of Core 4 Engineering, Inc. in Mequon, Wisconsin explains why Core 4 Engineering chose DELTABEAM®, “We chose to use Deltabeam in order to maintain a visually appealing structure that had design flexibility to transfer loads from the structure above making working with DELTABEAM® simple and efficient.”
Another advantage of using DELTABEAM® for this project was Peikko’s Engineering team’s involvement and assistance in solving design issues.
“Their design team was easy to connect with and we were able to use their expertise to solve the unique engineering issues we had on the project”, added Mr. Spiering.
In podium projects faced with height restrictions, DELTABEAM® often becomes the only available option to provide more headroom.