AIR TIGHTNESS OF STRAW BALE CONSTRUCTION

Straw bale construction offers a renewable,sustainable and proven alternative to mainstream building methods;still,little is known about its airflow characteristics.To this end,the intent of this paper is to evaluate airtightness of fully constructed and plastered straw bale walls as well as individual plain straw bales.The first experiment entailed measuring the influence of straw bale orientation on airflow characteristics with the finding that straw bale considered alone has poor air flow-retarding characteristics and that plaster is the primary air barrier.A second experiment involved thirty plastered straw bale specimens using three different plaster types.From this experiment,a crack grading system was developed and is herein proposed as a tool to evaluate plaster performance as an air barrier.A third experiment validated the crack grade system through application on four fully constructed straw bale walls.Practical use of the crack grading system was demonstrated on a case study straw bale house in Radomlje,Slovenia,where the predicted air tightness results were validated through comparison to results of blower door tests.

THE RELATIONSHIP BETWEEN COMFORT PERCEPTIONS AND ACADEMIC PERFORMANCE IN UNIVERSITY CLASSROOM BUILDINGS

This paper presents preliminary data on a series of building comfort experiments conducted in the field.We performed physical in-situ measurements and solicited responses from 409(184 female;225 male)university students in six different classrooms at the University of Massachusetts-Amherst during three seasons(fall,winter and spring).Our questions focused on student perception of comfort in varied environmental(temperature and humidity,and air speed)conditions.We collected records of student academic performance in the classes,correlating their comfort perceptions to their test scores.Statistical analysis of classroom environ-mental variables,thermal satisfaction,and student scores suggest that by enhancing thermal comfort,we can improve academic performance.

BUILDING WITH BAMBOO: A REVIEW OF CULM CONNECTION TECHNOLOGY

Interest in the engineering performance of bamboo is on the rise primarily due to its rapid regenerative qualities and high strength-to-weight ratio.It has been a standard,sustainable building material for thousands of years in Asia and South America,where it grows naturally.Although there are many examples of magnificent bamboo structures,standards and documentation on safe and reliable bamboo design are scarce,particularly for connection design.Traditional connections involve friction-tight lashings(eg.ropes and cords of dried grasses)and pin-and-socket connections such as dowels and pegs,but more recent advances have involved integration with steel hardware and concrete.This paper presents bamboo as a feasible alternative building material and presents a review of past,current and emerging technologies to join hollow bamboo culms in structural applications.The paper’s intent is to give an overview of the current state of bamboo connection technology and to promote developments in the emerging field of bamboo engineering.Recent technological advances and visionary architects have proven that it is possible to create safe structures that are not only sustainable but have tremendous potential for use in disaster relief and quick-build scenarios.