Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Impact of different water penetration criteria and cavity ventilation rates on the risk of mold growth in timber frame walls with brick veneer cladding

Kahangi shahreza, S LU and Abdul hamid, A LU orcid (2023) In Journal of Physics: Conference Series 2654.
Abstract
The present paper investigates the impact of different water penetration criteria on the risk for damage in a common type of building envelope in Nordic countries, timber frame walls with brick masonry veneer. The studied walls are evaluated based on one damage criterion, the risk of mold growth. The study investigates several parameters: water penetration criterion, type of moisture source (uniformly distributed or point source) and its position in the wall assembly, air change rate (ACR) (representing different workmanship scenarios), wind-driven rain (WDR) coefficient, and locations (Gothenburg and Rensjön, with different average annual rainfall and temperature). Two criteria on how to implement water penetration are compared: a) a... (More)
The present paper investigates the impact of different water penetration criteria on the risk for damage in a common type of building envelope in Nordic countries, timber frame walls with brick masonry veneer. The studied walls are evaluated based on one damage criterion, the risk of mold growth. The study investigates several parameters: water penetration criterion, type of moisture source (uniformly distributed or point source) and its position in the wall assembly, air change rate (ACR) (representing different workmanship scenarios), wind-driven rain (WDR) coefficient, and locations (Gothenburg and Rensjön, with different average annual rainfall and temperature). Two criteria on how to implement water penetration are compared: a) a commonly accepted reference model that assumes one percent of all wind-driven rain deposited on the façade to penetrate the clay brick cladding, and b) a new criterion stating that 3.8% of WDR penetrates when the water content of the brick veneer cladding is above 90% of its saturation capacity. The simulation is done for a thirteen-year period with WUFI Pro and WUFI 2D. The results indicate the greater importance of implementing water penetration compared to ventilation in cavities. Further, the findings suggest that the moisture source's location significantly impacts the mold growth risk. The results also show that the choice of the WDR coefficient affects the risks, which suggests that this factor needs accurate quantification for hygrothermal analyses. The results in this study suggest that an effective measure for the design/maintenance of such walls should incorporate: a) limiting the amount of water penetrating through the cladding, particularly stopping water from reaching the sensitive elements, i.e., timber studs, b) removing extruded mortar stemming from poor workmanship, if any, which may act as a capillary bridge. (Less)
Please use this url to cite or link to this publication:
author
and
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Physics: Conference Series
volume
2654
pages
11 pages
publisher
IOP Publishing
external identifiers
  • scopus:85181168738
ISSN
1742-6596
DOI
10.1088/1742-6596/2654/1/012028
project
Rational and Relevant Repointing of Clay Brick Facades - Technology, Conservation, and Economics
language
English
LU publication?
yes
id
0cdbadfb-6431-44d6-8c1d-27e3d6a42a60
date added to LUP
2024-03-03 01:35:22
date last changed
2024-04-19 11:13:02
@article{0cdbadfb-6431-44d6-8c1d-27e3d6a42a60,
  abstract     = {{The present paper investigates the impact of different water penetration criteria on the risk for damage in a common type of building envelope in Nordic countries, timber frame walls with brick masonry veneer. The studied walls are evaluated based on one damage criterion, the risk of mold growth. The study investigates several parameters: water penetration criterion, type of moisture source (uniformly distributed or point source) and its position in the wall assembly, air change rate (ACR) (representing different workmanship scenarios), wind-driven rain (WDR) coefficient, and locations (Gothenburg and Rensjön, with different average annual rainfall and temperature). Two criteria on how to implement water penetration are compared: a) a commonly accepted reference model that assumes one percent of all wind-driven rain deposited on the façade to penetrate the clay brick cladding, and b) a new criterion stating that 3.8% of WDR penetrates when the water content of the brick veneer cladding is above 90% of its saturation capacity. The simulation is done for a thirteen-year period with WUFI Pro and WUFI 2D. The results indicate the greater importance of implementing water penetration compared to ventilation in cavities. Further, the findings suggest that the moisture source's location significantly impacts the mold growth risk. The results also show that the choice of the WDR coefficient affects the risks, which suggests that this factor needs accurate quantification for hygrothermal analyses. The results in this study suggest that an effective measure for the design/maintenance of such walls should incorporate: a) limiting the amount of water penetrating through the cladding, particularly stopping water from reaching the sensitive elements, i.e., timber studs, b) removing extruded mortar stemming from poor workmanship, if any, which may act as a capillary bridge.}},
  author       = {{Kahangi shahreza, S and Abdul hamid, A}},
  issn         = {{1742-6596}},
  language     = {{eng}},
  month        = {{12}},
  publisher    = {{IOP Publishing}},
  series       = {{Journal of Physics: Conference Series}},
  title        = {{Impact of different water penetration criteria and cavity ventilation rates on the risk of mold growth in timber frame walls with brick veneer cladding}},
  url          = {{http://dx.doi.org/10.1088/1742-6596/2654/1/012028}},
  doi          = {{10.1088/1742-6596/2654/1/012028}},
  volume       = {{2654}},
  year         = {{2023}},
}