Water penetration and condensation can cripple a building. With 85% of U.S. construction-rated claims tied to uncontrolled rainwater penetration, it’s a common issue — especially when design and construction timelines are stretched to meet demand.

Data centers may be at the highest risk. Not only due to their quick turnover schedules, but because the smallest water penetration in a critical location can lead to equipment downtime with an average cost close to $9K per minute.1 

What can be done to help create a quality data center when various trades, time, and climate are influencing overall quality?

Enter building envelope commissioning (BECx). A low-cost additional service when compared to the cost of a down facility.

BECx is a head-to-toe third-party review of a building’s envelope during all phases of a project from design through occupancy. The goal of this review is to identify areas of concern for air/water leaks, sequencing, constructability, and more before they become costly issues to resolve post-construction. BECx also serves as an opportunity to educate facilities staff on how to maintain a building to meet its intended lifespan.

Projects that adopt BECx have the potential to achieve two valuable LEED® points under Enhanced Commissioning Option 2: Envelope Commissioning. To achieve this credit, there are no required envelope tests; rather, the client is to engage with an experienced BECx authority (BECxA) to help determine what envelope tests make sense based on the data center’s complexity, budget, and goals. To date, LEED has been the primary driver for a recent increase in BECx at data centers.


Getting BECX right – the process

It’s recommended that a BECxA is contracted by mid-design (50% design development) to deliver the greatest ROI. This follows the 1-10-100 rule,2  where issues are less costly to resolve during the design stage versus during or after construction. The following steps summarize ESD’s recommended BECx process which follows LEED v4’s requirements and referenced standards: NIBS Guideline 3-2012 and ASHRAE Guideline 0-2005.


Step 1: Hire an experienced and accredited third-party BECxA with the following credentials:

  • Has previous project experience on at least two similar projects

Holds one or more of the following accreditations:

  • Professional architecture licensure (AIA, NCARB, RA)
  • Building envelope accreditation (BECxP, CxA+BE, RRC, NEEB Certified, RBEC)

Spray hoseFIGURE 1. Spray hose test at roof to wall intersection. Simulated wind driven rain to test for water penetration.


Step 2: Conduct envelope design review

The BECxA is to review the envelope drawings at least twice — once at 50% design development followed by a second review (back-check) by 50% construction documents to ensure the comments were reviewed/addressed by the architect to meet the LEED v4 requirements. More design reviews are recommended if a project’s design is complicated (e.g., multiple materials, complex shape). In addition to the BECxA providing envelope reviews, the roofing consultant will review the roofing drawings to ensure the design of the roof assembly isn’t affecting the roofing warranty.