Durability of Internally Insulated Historical Solid Masonry Under Future Climates: A Stochastic Approach

Sahyoun, Sahar; Wang, Lin; Ge, Hua; Defo, Maurice; Lacasse, Michael A.

doi:10.23967/dbmc.2020.044

Cited by 5 publications

(8 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Further, Hao et al studied mould growth, interstitial condensation and freeze-thaw damage in interior insulated historical Alpine buildings [16]. Sahyoun et al assessed the freeze-thaw risk in interior insulated historical masonry walls in Ottawa, Canada [17]. Hedayatnia et al worked on material damages in heritage buildings in Iran [18].…”

Section: Introductionmentioning

confidence: 99%

Factorial Study on the Impact of Climate Change on Freeze-Thaw Damage, Mould Growth and Wood Decay in Solid Masonry Walls in Brussels

2021

View full text Add to dashboard Cite

Previous studies show that climate change has an impact on the damage risks in solid masonry facades. To conserve these valuable buildings, it is important to determine the projected change in damages for the original and internally insulated cases. Since historical masonry covers a wide range of properties, it is unknown how sensitive the climate change impact is to variations in different parameters, such as wall thickness, brick type, etc. A factorial study is performed to determine the climate change impact on freeze-thaw risk, mould growth and wood decay in solid masonry in Brussels, Belgium. It is found that the critical orientation equals the critical wind-driven rain orientation and does not change over time. Further, the freeze-thaw risk is generally decreasing, whereas the change in mould growth and wood decay depends on the climate scenario. Knowing the brick type and rain exposure coefficient is most important when assessing the climate change impact. For freeze-thaw risk and wood decay, it is found that simulating one wall thickness for the uninsulated and one insulated case is sufficient to represent the climate change impact. Finally, the effects of climate change generally do not compensate for the increase in damage after the application of internal insulation.

show abstract

Section: Introductionmentioning

confidence: 99%

Factorial Study on the Impact of Climate Change on Freeze-Thaw Damage, Mould Growth and Wood Decay in Solid Masonry Walls in Brussels

2021

View full text Add to dashboard Cite

show abstract

“…A well-accepted method to assess the frost damage risk of masonry buildings is by counting the freeze-thaw cycles that their building materials experience. The freeze-thaw events can be calculated by considering climate-based indices (Viles, 2002;Grossi et al, 2007;Sabbioni et al, 2010;Leissner et al, 2015;Loli and Bertolin, 2018) or material response-based indices (Sedlbauer and Kunzel, 2000;Straube and Burnett, 2005;Straube and Schumacher, 2006;Mantha and Arena, 2012;De Rose et al, 2014;Van Aarle et al, 2015;Vandemeulebroucke et al, 2019Vandemeulebroucke et al, , 2020Vandemeulebroucke et al, , 2021aZhou et al, 2020;Hao et al, 2020;Sahyoun et al, 2020).…”

Section: Introductionmentioning

confidence: 99%

“…On the contrary, above the S crit , damage is measurable after only a few cycles (Fagerlund, 1977a, b;Mensinga et al, 2010;Straube et al, 2012;Ueno et al, 2013a, b, c;De Rose et al, 2014;Van Straaten et al, 2016). The lowest value of the S crit defined experimentally for a brick is 0.25 (Mensinga et al, 2010) and it was adopted by a lot of studies that included numerical simulations, such as Zhou et al (2017), Vandemeulebroucke et al (2019, 2021a, Sahyoun et al (2020), Zhou et al (2020). Other studies (Sedlbauer and Kunzel, 2000;Straube and Schumacher, 2006;Mantha and Arena, 2012;Ueno et al, 2013a, b, c;WTA, 2014;De Rose et al, 2014;Van Aarle et al, 2015;Van Straaten et al, 2016;Said et al, 2020) suggested higher values for the S crit , ranging from 0.3 to 0.9.…”

Section: Introductionmentioning

confidence: 99%

Assessment of frost damage risk in a historic masonry wall due to climate change

2023

View full text Add to dashboard Cite

Abstract. Historic masonry buildings are an integral part of human cultural heritage, and they need to be preserved for future generations. Brick is susceptible to frost damage which is common in regions with cold and humid climates. The frost damage on the masonry walls is accumulated over the years becoming more and more critical for the integrity of the historic buildings and it is also affected by climate change (CC). In the current research, the focus was placed on a coastal region in southern Norway with a significant number of historic masonry buildings. The frost damage risk of the masonry walls was assessed by using data from a climate reanalysis for the present conditions and from a climate model under past, present, and future conditions. Two climate-based (CB) indices accounting for the air temperature and one material response-based (MRB) index considering the temperature and moisture content inside a simulated masonry wall were used for the frost damage risk assessment. The inputs for the MRB index were calculated by heat, air, and moisture (HAM) transfer simulations. Within the HAM simulations, the indoor climate was in one case representative of an unconditioned building with air leakages and many openings, while in the second case it was representative of a small, conditioned room. The overall impact of CC was a decrease in the frost damage risk of the masonry walls. However, an increased frost damage risk was observed from the present to the future conditions according to the MRB index for the walls of small, conditioned rooms with higher driving rain load and lower solar radiation gains. The (i) number of freeze-thaw events, (ii) periods during which freeze-thaw events occur, and (iii) CC-related trends varied based on the considered index with the most explicit risk assessment being the MRB one. Moreover, the freeze-thaw events experienced by the masonry walls of unconditioned, leaky buildings were 20 times more than the ones for the small, conditioned rooms. Significant differences were observed between the results from the climate model and the climate reanalysis which were mainly linked to the underestimation of the air temperature and the overestimation of the precipitation by the climate model. The outputs of the MRB index were translated into certain damage categories while suggestions on improving the limitations of the current research were made.

show abstract

“…A summary of how climate change will impact hygrothermal performance of structures is given in Lacasse et al (2020). Studies which examined the effects of future climates on historic masonry have been performed and shown increasing risk of freeze-thaw damage in some climates (Orr et al, 2018;Sahyoun et al, 2020;Vandemeulebroucke et al, 2020).…”

Section: Exterior Climatementioning

confidence: 99%

“…A stochastic approach may be more appropriate as first outlined by Salonvaara (2001). Further examples of stochastic hygrothermal models have been performed often with a view toward calibration (Akkurt et al, 2020;Freudenberg et al, 2017;Goffart et al, 2017;Sahyoun et al, 2020;Zhao et al, 2011). Some blocks to stochastic hygrothermal modelling in practice, include the increased set-up and simulation time and lack of easy-to-use software that can handle this problem.…”

Section: Materials Propertiesmentioning

confidence: 99%

Evaluating Uncertainty in Hygrothermal Modelling of Heritage Masonry Buildings

Gutland¹

View full text Add to dashboard Cite

Hygrothermal models are important tools for assessing durability risks in building envelopes, such as biological growth (mould and wood rot fungi), corrosion and freeze-thaw action in masonry. Hygrothermal modelling of mass masonry wall assemblies are known to have numerous weaknesses and gaps in our understanding. First, there are significant uncertainties relating to model inputs including material properties and boundary conditions. Second, it is difficult to calibrate model results against data measured in the field. Third, two and threedimensional interactions between adjacent materials in masonry assemblies are poorly understood and are rarely modelled in practice. And fourth, geometric irregularities, imperfections and the effects of decay are rarely considered by modellers. Combined, these uncertainties can lead to reduced confidence in the model's conclusion and alter our opinions on the durability risks and whether retrofits such as interior insulation are appropriate or not. This doctoral thesis examines how uncertainty factors into hygrothermal modelling of heritage masonry, and how it can be reduced, and or, acknowledged in practice. This is demonstrated using a combination of simulation studies and on-site monitoring work. Three peer-reviewed papers which demonstrate examples of uncertainty in hygrothermal modelling are presented.The first paper presents a methodology for integrating calibrated hygrothermal and energy models of the Southwest Tower of the East Block for the purpose of assessing durability. This project consisted of in-situ monitoring of the masonry and ii interior climate of the Southwest Tower for over a year. The calibrated energy model was used as basis for estimating the net benefit of interior climate retrofits on the durability of the masonry. The calibrated hygrothermal model was not as successful, but the lessons learned were transferable to the third paper.The second paper examines the imperfect nature of the mortar-unit interface in masonry and how this affects moisture transfer into and out of the wall. Simulations showed that modelling this interface explicitly as a fracture will increase water absorption during wetting periods, but also help slightly with releasing moisture under drying conditions.The third paper examines the uncertainty in geometry and construction of the rubble core walls of the East Block. The wall's stack pattern is highly irregular and the core of the walls are known to have significant levels of voids which can act like insulating layers, or act as mini-rainscreens slowing moisture transfer into the wall. A Python script was developed to stochastically-generate sections of walls with and without voids. A significant variation in state variables, and heat and moisture fluxes was found between stochastically generated geometries in the mortar joints and in the rubble core. This variation increased with the number of voids.Overall, this research contributes to efforts make hygrothermal modelling of masonry more accurate and more intuitive for practiti...

show abstract

Durability of Internally Insulated Historical Solid Masonry Under Future Climates: A Stochastic Approach

Cited by 5 publications

References 6 publications

Factorial Study on the Impact of Climate Change on Freeze-Thaw Damage, Mould Growth and Wood Decay in Solid Masonry Walls in Brussels

Factorial Study on the Impact of Climate Change on Freeze-Thaw Damage, Mould Growth and Wood Decay in Solid Masonry Walls in Brussels

Assessment of frost damage risk in a historic masonry wall due to climate change

Evaluating Uncertainty in Hygrothermal Modelling of Heritage Masonry Buildings

Contact Info

Product

Resources

About