Monitored Indoor Environmental Quality of a Mass Timber Office Building: A Case Study

Jason Stenson,Andrew Loia,Dale Northcutt,Aurélie Laguerre,Mariapaola Riggio,Georgia Maccrone,Elliott T Gall,Suzanne L Ishaq,Kevin Van Den Wymelenberg,Andre Barbosa,Ignace Mugabo

doi:10.3390/buildings9060142

Jason Stenson, Andrew Loia + Show 9 more

Open Access

https://doi.org/10.3390/buildings9060142

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Abstract

A broad range of building performance monitoring, sampling, and evaluation was conducted periodically after construction and spanning more than a year, for an occupied office building constructed using mass timber elements such as cross-laminated timber (CLT) floor and roof panels, as well as glue-laminated timber (GLT) beams and columns. This case study contributes research on monitoring indoor environmental quality in buildings, describing one of the few studies of an occupied mass timber building, and analyzing data in three areas that impact occupant experience: indoor air quality, bacterial community composition, and floor vibration. As a whole, the building was found to perform well. Volatile organic compounds (VOCs), including formaldehyde, were analyzed using multiple methods. Formaldehyde was found to be present in the building, though levels were below most recommended exposure limits. The source of formaldehyde was not able to be identified in this study. The richness of the bacterial community was affected by the height of sampling with respect to the floor, and richness and composition was affected by the location within the building. Floor vibration was observed to be below recognized human comfort thresholds.

Highlights

Mass timber wood products are gaining adoption in US buildings through changes to building codes and standards [1,2], as well as specialized manufacturing facilities coming on-line.Prefabricated panelized products like Cross-Laminated Timber (CLT), Dowel-Laminated Timber (DLT), Nail-Laminated Timber (NLT) and Mass Plywood Panels (MPP) are able to be used as structural floor, roof and wall assemblies
During sampling weeks 3 and 4, passive whole air helium diffusion sampling (HeDS) for analysis of Volatile organic compounds (VOCs) was added to the indoor kits [18]. 1-liter canisters (Entech, Bottle-Vac) filled with helium to a slight positive pressure were deployed in triplicate at each location
The V3 and V4 (319F-806R) regions of the 16S rRNA gene were polymerase chain reaction (PCR) -amplified following a previously described protocol [23], and amplicons were purified with a bead-based clean-up using Mag-Bind RxnPure Plus (Omega Bio-tek, Norcross, GA, USA)

Summary

Introduction

Mass timber wood products are gaining adoption in US buildings through changes to building codes and standards [1,2], as well as specialized manufacturing facilities coming on-line. Prefabricated panelized products like Cross-Laminated Timber (CLT), Dowel-Laminated Timber (DLT), Nail-Laminated Timber (NLT) and Mass Plywood Panels (MPP) are able to be used as structural floor, roof and wall assemblies These structural elements impact the type and distribution of major materials used throughout a mass timber building as compared to other construction types. This case study contributes to research on monitoring IEQ in buildings, describing one of the few studies of an occupied mass timber building, and using exposure measurement methods for three important factors: indoor air quality, indoor bacterial community and vibrational comfort. This case study investigates performance of a mass timber building; how building materials and assemblies impact indoor air quality, indoor bacterial community, and vibration in an office environment of an occupied mass timber building. The floor assembly is comprised of 105 mm 3-lam CLT, 25 mm gypcrete topping, and carpet squares without a pad

Indoor Air Quality

PlanofofAlbina

Bacterial

Vertical Vibration

Results

Bacterial Community