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Fuktbelastning i takkonstruktioner med perforerad ångspärr

Georgsdottir, Tina and Sawirs, Emely (2012)
Programmes in Helesingborg
Abstract
Moisture in roof constructions is currently a major concern in the building industry, especially in Sweden where the climate is often wet and the dry season short. In order to avoid these problems in the future there needs to be a greater understanding and focus on building techniques that prevent mold problems. Crucial to mold prevention is the vapor retarder, which is relied heavily upon in roof construction in order to prevent the airflow between indoor spaces and the construction itself. In most theoretical models this retarder is viewed as flawless, however this is often not the reality. The purpose of this study is to investigate the moisture and related mold problems associated with different degrees of perforation in the vapor... (More)
Moisture in roof constructions is currently a major concern in the building industry, especially in Sweden where the climate is often wet and the dry season short. In order to avoid these problems in the future there needs to be a greater understanding and focus on building techniques that prevent mold problems. Crucial to mold prevention is the vapor retarder, which is relied heavily upon in roof construction in order to prevent the airflow between indoor spaces and the construction itself. In most theoretical models this retarder is viewed as flawless, however this is often not the reality. The purpose of this study is to investigate the moisture and related mold problems associated with different degrees of perforation in the vapor retarder in two different types of roof constructions, a non-ventilated pitched roof and a traditional ventilated pitched roof. The constructions are located in Lund and Luleå and two different vapor retarders are tested, so there are four different constructions for each location: Ventilated inclined roof with glass wool slabs and Isover Vario KM Duplex UV (S.201) Ventilated inclined roof with glass wool slabs and Isover Vapor retarder (S201) Non-ventilated inclined roof with glass wool slabs and Isover Vario KM Duplex UV (S.204) Non-ventilated inclined roof with glass wool slabs and Isover Vapor retarder (S.204)
Simulations have been made in the program WUFI Pro 5.1. Results from WUFI have been analyzed in a mold dosage model developed at Lunds Technical University. The results of simulations performed in this study show that the traditional ventilated pitched roof performs better than the non-ventilated pitched roof when a perforation exists in the vapor retarder. Generally the smallest of the studied perforations (d=5 mm per m^2 roof area) is acceptable in the ventilated pitched roof but larger holes lead to extensive mold growth. In the non-ventilated compact roof a hole in the vapor retarder cannot be accepted according to calculations in this study. The study also shows that the variable vapor barrier works slightly better than the normal vapor retarder and that Luleå is a better climate than Lund from a mold growth perspective. Keywords: Moisture, WUFI, vapor retarder, vapor barrier, Isover, dosage model, mold growth. (Less)
Please use this url to cite or link to this publication:
author
Georgsdottir, Tina and Sawirs, Emely
organization
year
type
M2 - Bachelor Degree
subject
keywords
wufi, ångspärr, variabel ångbroms, isover, dosmodellen, mögelpåväxt
language
Swedish
id
2797821
alternative location
http://portal.ch.lu.se/Campus.NET/Services/Publication/Export.aspx?id=2275&type=doc
date added to LUP
2012-06-15
date last changed
2012-07-12 15:39:50
@misc{2797821,
  abstract     = {Moisture in roof constructions is currently a major concern in the building industry, especially in Sweden where the climate is often wet and the dry season short. In order to avoid these problems in the future there needs to be a greater understanding and focus on building techniques that prevent mold problems. Crucial to mold prevention is the vapor retarder, which is relied heavily upon in roof construction in order to prevent the airflow between indoor spaces and the construction itself. In most theoretical models this retarder is viewed as flawless, however this is often not the reality. The purpose of this study is to investigate the moisture and related mold problems associated with different degrees of perforation in the vapor retarder in two different types of roof constructions, a non-ventilated pitched roof and a traditional ventilated pitched roof. The constructions are located in Lund and Luleå and two different vapor retarders are tested, so there are four different constructions for each location: Ventilated inclined roof with glass wool slabs and Isover Vario KM Duplex UV (S.201) Ventilated inclined roof with glass wool slabs and Isover Vapor retarder (S201) Non-ventilated inclined roof with glass wool slabs and Isover Vario KM Duplex UV (S.204) Non-ventilated inclined roof with glass wool slabs and Isover Vapor retarder (S.204)
Simulations have been made in the program WUFI Pro 5.1. Results from WUFI have been analyzed in a mold dosage model developed at Lunds Technical University. The results of simulations performed in this study show that the traditional ventilated pitched roof performs better than the non-ventilated pitched roof when a perforation exists in the vapor retarder. Generally the smallest of the studied perforations (d=5 mm per m^2 roof area) is acceptable in the ventilated pitched roof but larger holes lead to extensive mold growth. In the non-ventilated compact roof a hole in the vapor retarder cannot be accepted according to calculations in this study. The study also shows that the variable vapor barrier works slightly better than the normal vapor retarder and that Luleå is a better climate than Lund from a mold growth perspective. Keywords: Moisture, WUFI, vapor retarder, vapor barrier, Isover, dosage model, mold growth.},
  author       = {Georgsdottir, Tina and Sawirs, Emely},
  keyword      = {wufi,ångspärr,variabel ångbroms,isover,dosmodellen,mögelpåväxt},
  language     = {swe},
  note         = {Student Paper},
  title        = {Fuktbelastning i takkonstruktioner med perforerad ångspärr},
  year         = {2012},
}