In wood-frame buildings of three or more stories, cumulative shrinkage can be significant and have an impact on the function and performance of finishes, openings, mechanical/electrical/plumbing (MEP) systems, and structural connections. However, as more designers look to wood-frame construction to improve the cost and sustainability of their mid-rise projects, many have learned that accommodating wood shrinkage is actually very straightforward. This publication will describe procedures for estimating wood shrinkage and provide detailing options that minimize its effects on building performance.
The growing availability and code acceptance of mass timber—i.e., large solid wood panel products such as cross laminated timber (CLT) and nail-laminated timber (NLT)—for floor, wall and roof construction has given designers a low-carbon alternative to steel, concrete, and masonry for many applications. However, the use of mass timber in multi-family and commercial buildings presents unique acoustic challenges.
While laboratory measurements of the impact and airborne sound isolation of traditional building assemblies such as light wood-frame, steel and concrete are widely available, fewer resources exist that quantify the acoustic performance of mass timber assemblies. Additionally, one of the most desired aspects of mass timber construction is the ability to leave a building’s structure exposed as finish, which createsthe need for asymmetric assemblies. With careful design and detailing, mass timber buildings can meet the acoustic performance expectations of most building types.
This client report on the acoustics research component regarding sound insulation of elements and systems for mid-rise wood buildings is structured into a main part and four appendices. The main part outlines the background, main research considerations and summarizes conducted research and major outcomes briefly. It is structured like the Acoustics tasks in the Statement of Work of the Mid-rise Wood research project to identify accomplishments. For details on the research, testing and results, the main part references to four appendices that contain more details including test plans, test methods, specimen descriptions and all test data that is vetted so far.
This report summarizes the acoustics research component regarding sound insulation of elements and systems for the research project on mid-rise and larger wood buildings. The summary outlines the background, main research considerations, research conducted and major outcomes. Further details of the design and the results can found in the appendix of Client Report A1-100035-02.1 .
The goal of the acoustics research components was to develop design solutions for mid-rise wood and wood-hybrid buildings that comply both with the current National Building Code of Canada (NBCC) 2010  requirements for direct sound insulation and with the anticipated requirements for flanking sound transmission in the proposed, 2015 version of the NBCC. In addition, the design solutions were to provide better impact sound insulation while still achieving code compliance for all other disciplines (interdependencies) as identified in the final report of the scoping study conducted in FY 2010/2011 
A. Shop Drawings and Details for Tests
B. Sound and Impact Test Results Summary
C. Test 1: Sound and Impact Transmission Test - CLT
D. Test 2: Sound and Impact Transmission Test - Concrete Topping
E. Test 3a: Sound and Impact Transmission Test - Marmoleum
F. Test 3b: Sound and Impact Transmission Test - Marmoleum
G. Test 4: Sound and Impact Transmission Test - Carpet
H. Test 5a: Sound and Impact Transmission Test - Luxury Vinyl Plank
I. Test 5b: Sound and Impact Transmission Test - Luxury Vinyl Plank
J. Test 6: Sound and Impact Transmission Test - Mechanical Roof
This report contains the transmission loss (TL) results measured in accordance with ASTM E90-09 and the normalized impact sound pressure level (NISPL) results measured in accordance with ASTM E492-09 of 13 cross-laminated timber (CLT) floor assemblies and 5 glulam floor assemblies. The report also contains the nonstandard impact sound pressure level results measured on 6 different small patch specimens.
Summary tables containing the specimen number, sketch, short description, the sound transmission class (STC) and impact isolation class (IIC) ratings, as well as, the page number of the detailed test reports are provided starting on page 5.
A brief analysis of the floors tested as part of this test series is provided after the summary tables on page 9. The standard test reports of the tested floor assemblies begin on page 16. The floor assemblies were built and tested between January and April 2016.
This report is published as an addendum to NRC Research Report RR-335 “Apparent Sound Insulation in Cross-Laminated Timber Buildings." It is intended that this addendum will be merged with RR-335 in the future as a report for predicting the sound insulation in buildings using mass-timber constructions including NLT assemblies. This report presents the results from experimental studies of airborne sound transmission through assemblies of nail-laminated timber (NLT) with various linings. To put the data presented in this report in the proper context, this report begins with a brief explanation of calculation procedures to predict the apparent sound transmission class (ASTC) between adjacent spaces in a building whose structure is a combination of mass-timber assemblies such as nail-laminated timber (NLT) or cross-laminated timber (CLT) panels.
When Adidas announced plans for a two-building expansion of their North American headquarters, speed and budget were key criteria. They wanted a campus that reflected their culture and commitment to quality, authenticity and innovation, but had a strict 24-month deadline. In response, the design and construction team chose a hybrid of precast concrete and mass timber for one building, and a mass timber post-and-beam solution for the other, using prefabrication to reduce the construction schedule by more than three months.