The developer of Baltimore’s first commercial mass timber office building downtown has revealed a modified design to optimize its construction plan and achieve cost savings in a challenging pandemic economy.
28 Walker的首席运营官Scott Slosson说，总部位于巴尔的摩的28 Walker Development最初计划建造一座五层楼，115,000平方英尺的建筑，但已确定一个四层楼的94,000平方英尺的结构更可行。该项目被称为波士顿街4010号
Slosson说，修改允许“调整地板以优化租赁深度”，并“增加特定于租户的私人室外空间”。他说，切换到“稍微不同的外立面计划”将有助于“将整体发展的各个组成部分联系在一起”。
The revelation comes fives months after the developer announced its plans in a Feb. 22 statement to build a five-story building at 4010 Boston St.
In addition to design considerations, the modifications should also achieve “a positive impact on timber pricing by reaching certain design efficiencies that coincide with optimal lease depths,” Slosson says.
“很高兴看到定价开始落在the timber front as we work through and finalize plans,” he adds. “We expect this will be helpful to the overall project budget.”
Utility and site work for the planned speculatively constructed building is scheduled to begin in early September, with the project now in permit documents. Foundation/podium work will follow in November and construction in March. Final completion is expected by August 2022 with occupancy by January 2023.
The project will be constructed in the 12-acre master-planned广州的混合用途集体“ 28 Walker选择根据材料的正能效率属性来利用重型木材，从而形成有机温暖的外部和室内设计，并带有地板，柱子和裸露的天花板。”开发商在2月份的声明中说。
分手的决定
British Columbia-based structural engineering and timber construction firm StructureCraft has been serving as engineer of record on the project since January, contracting directly with Richmond, Va.-based Mosely Architects Inc.’s design team, says Drew Willms, StructureCraft business development engineer. “We are still early in the redesign process so new fabrication and delivery dates for the mass timber components haven’t been established,” he says.
The building will include dowel laminated timber (DLT) for the floor and roof, he says and cross laminated timber (CLT) and spruce glulam beams and columns likely sourced from Austria, Willms says.
In April, StructureCraft transitioned to its current role as a furnish and install subcontractor to Reisterstown, Md.-based Chesapeake Contracting Group, general contractor for the project under a guaranteed maximum price integrated project delivery agreement.
Chesapeake副总裁兼项目主管Dan Hannon说，切萨皮克选择将IV型重型木材建筑的许可过程分为两个阶段，以加快建设的速度。
A foundation-only permit will allow for work below the slab and on the concrete podium in November and a full-building permit will allow for work on the entire building by next March, Slosson says.
At level one, Chesapeake plans to cast a 4,500-psi concrete podium in November to allow for parking, Hannon says. “It is preferable as a non-combustible construction material and will allow for the incorporation of retail stores below the office building.”
Willms解释说，一级上的混凝土剪力墙将作为建筑物的主要横向抗压系统，例如，在两个楼梯轴和单个电梯轴周围。他指出，在高公平的平板上方，建筑物完全成为木材，核心向CLT过渡。这与其他构造型框架，混凝土或预制剪切壁作为侧面系统采用了更多的混合方法形成对比。
Hidden HVAC
摩斯建筑师和他们的机械电气and plumbing (MEP) designers designed a raised access floor (RAF) system that will hide a majority of the heating, ventilation and air conditioning and high and low voltage electrical cabling system below the floor, Hannon says. “One full inch of Gypcrete must be in place before the raised floor system can be installed,” he says. Understanding the sequence of the installation and the incorporation of the other MEP trades into the system is the biggest challenge to date, he says.
“Since almost all of the MEP systems will be built within the interstitial space of the RAF, each trade will secure their runway within the system to deploy their specific design and installation,” he says.
Matthew Ormsby, associate at Mosely Architects adds that the building will be designed to meet the city's adopted version of the国际绿色建筑法规(IgCC), including an underfloor air distribution system with high return air designed to provide a healthier indoor environment.
Coordination and Logistics
Chesapeake is coordinating a host of logistical challenges as part of a brownfield development on a former Exxon property, including staging, access, crane swings and environmental controls, Hannon says. In working with an adjacent property Greystar Real Estate Partners, which had two tower cranes in operation, both parties had to decide on a crane swing radius to determine who would be at what height, he notes. “Since this is also a retail parcel with an office building … we also had to coordinate the travel path with the developer as not to disrupt any of their clients,” he says. The solution reached involved having each party swinging over top of a small portion of each other’s property and positioning each crane at an elevation to avoid any collisions, he says.
Twin Timber
切萨皮克（Chesapeake）还建立了一个多户住宅项目，即2001年的Aliceanna，位于波士顿街4010号的拐角处，所有者希望修剪该项目的费用，因此Chesapeake接近结构图馆以寻求解决方案。18luck.cub作为设计/工程过程的一部分，构造构造提议删除建筑物的结构钢外骨骼并用木材外骨骼代替，这意味着很快将在巴尔的摩完成两个大规模木材项目。18luck官网
“We worked with Hord Copeland Macht and Elm Street Development in unison to redesign the exoskeleton out of wood in lieu of structural steel and plan on erecting that structure simultaneously with the project we doing with 28 Walker,” he says.
“It’s a much smaller project, but very elegant,” Hannon says.
