THESIS ABSTRACT
AUTHOR: ABDULAZIZ OMER ABDULLAH AL-AJAJI
TITLE OF STUDY: WATERPROOFING OF ROOFS OF RESIDENTIAL
BUILDINGS IN SAUDI ARABIA
DATE OF DEGREE: JUNE 1996
This study investigates the construction practices of the most
important element in a residential building, the roof, with great emphasis on
the most important component in roofing, the waterproofing. There is a large
variety of materials that are available in the market for each roofing
component. Owners usually spend lots of time trying to have the best
roofing by looking for the best materials for each roofing component and at
the end they face problems. The study reveals that wasting time by trying to
get the best materials is the wrong approach to having a good roofing
system; rather the selection of a reputable contractor is much more vital.
Problems caused by materials are insignificant compared to design and
construction methods.
More than a third (36%) of houses encountered major roofing
problems. Three percent encountered disastrous problems where the whole
roof had to be dismantled and replaced by completely new roofs. These
problems were faced as a result of bad designs and construction practices
such as: poor inspection and maintenance, bad slope, use of small size of
drainage outlets, installation of sloping concrete screed on a non-firm base
with no reinforcement and/or expansion joints, having dead level roofs until
problems occurred, and installation of waterproofing membrane on a nonsloped surface.