Future Risks on Moisture Safety in Ventilated Parallel Roofs: A Numerical Study of a Common Roof Type in Sweden Subjected to Future Weather Data Sets
Typ
Examensarbete för masterexamen
Master's Thesis
Master's Thesis
Program
Structural engineering and building technology (MPSEB), MSc
Publicerad
2022
Författare
Allinger, Alice
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
The climate is changing. The prognoses are a higher outdoor temperature and an
increased absolute vapour content in outdoor air for all of Sweden. In Sweden today
many roofs are already subjected to moisture-related damages and the guidelines for
moisture safe design roofs are sparse.
Two different roof constructions are normally used in Sweden today: the attic and the
ventilated parallel roof. The ventilated parallel roof has not been evaluated for a future
climate. The purpose of this study is to investigate the moisture safety of ventilated
parallel roofs subjected to a data set of future climates. The effect of orientation,
inclination, colour and additional exterior insulation is evaluated for different locations
in Sweden.
Parallel roofs in Sweden are often ventilated by natural driving forces: wind and thermal
buoyance. The model of the study considers a full data set of meteorological data for
calculating directional dependent thermal buoyance, moisture infiltration from indoor
to outdoor due to pressure differences, and moisture and heat transport through the
roof.
The result shows a future increased risk of mould growth in ventilated parallel roofs in
all of Sweden. North is the dimensioning orientation. The most efficient way of reducing
the risk is to use a reflective and bright-coloured roof.
Beskrivning
Ämne/nyckelord
moisture safety, mould growth, numerical study, ventilation, parallel roof, air cavity, climate change, gable roof