Lisø PhD Dissertation Manuscript - NTNU

important drivers for change. In retrospect, it looks as though extensive city fires entailed a
mental change amongst the citizens, as they were willing to accept restricted proprietary
rights. ”Murtvangsloven" (“the Brick Restraint Act” of 19 May 1904), prohibiting the
erection of wooden houses in Norwegian cities, represented a considerable intermezzo in
the debate on building regulation and was at that time perceived as a change of paradigm.
The traditional dense built Norwegian wooden cities were virtually given a deathblow. The
formidable fire in Ålesund in the same year (one of the most severe fire catastrophes in
Norway through the ages) accelerated the enforcement of the Act.
Today, masonry in Norway is primarily employed in large buildings (e.g. office
and enterprise buildings and apartment buildings). However, several years of persistent
marketing from masonry manufacturers and contractors have produced the intended result,
as there is also now an increase in the use of masonry in domestic building. Leca (owned
by maxit Group, a part of the German company Heidelberg Cement), the largest
manufacturer of masonry units, in co-operation with several prefab house manufacturers,
has recently developed a catalogue of small masonry houses. Masonry houses are being
marketed as virtually “maintenance-free” buildings, as opposed to wooden buildings where
one according to Norwegian television commercials are subject to a slave-like dependence
on the bucket of paint.
1.2. International research focus
Even though masonry structures are normally considered “maintenance-free”, if properly
designed and constructed, they are undoubtedly vulnerable to damage and defects in harsh
climates with high frost and driving rain exposure. It is therefore of utmost importance to
recognize the most significant challenges concerning design of masonry structures in
severe climates in order to establish research and education efforts. Analyses of building
defects should form part of approaches aimed at revealing these challenges.
Research work presented at the latest international masonry conference, “13 th
International Brick/Block Masonry Conference” [1], forms a clear picture of high-priority
research areas for masonry research. About half of the 143 papers presented at the
conference dealt with mechanical properties or mechanical behaviour of masonry, while
durability, material properties or material behaviour influenced by moisture was the main
focus in a mere 15% of the papers. The same bias was also apparent at the “6 th
International Masonry Conference” in London two years earlier [2]. Scientific studies of
masonry defects are almost absent in international journals.
1.3. Objective and scope
This paper presents challenges concerning design of masonry structures under severe
climatic conditions, based on lessons learned from two decades of process induced
building defect investigations. First, results from a review of 302 building defect
assignments related to masonry in the 20-year period 1983-2002 are presented. Next, a
case study of flaws and defects revealed as part of a comprehensive investigation carried
out ahead of the rehabilitation of His Majesty the King’s Guard Huseby Barracks is
provided. Finally, lessons to be learned and implemented in the future design of climateadapted
masonry structures are discussed.
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