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Denne rapport beskriver resultaterne fra forskningsprojektet: Luftudveksling mellem bolig og tagrum. I projektet blev det undersøgt, i hvilket omfang der sker udveksling af luft mellem bolig og uudnyttede tagrum. Målet var på sigt at kunne vurdere, hvilken betydning mulig skimmelsvamp i et tagrum har for eksponeringen i den underliggende bolig samt at kunne vurdere fugtoverførslen fra boligen til uopvarmede tagrum.Luftudvekslingen mellem boliger og udnyttede uopvarmede tagrum blev undersøgt ved en passiv sporgasmetode. Metoden blev anvendt ved placering af to typer sporgasser i hver sin zone, hhv. bolig og tagrum. På baggrund af målte koncentrationsniveauer i de respektive zoner, samt beregnede emissionsrater baseret på temperaturmålinger, kunne udvekslingen mellem zonerne bestemmes, foruden luftskifterne i de to zoner. Der indgik 30 huse i undersøgelsen, og målingerne blev foretaget i to perioder for hvert hus; hhv. en kold og en varm periode. De 30 huse fordelte sig på byggeår fra 1920’erne til 2010’erne, et enkelt hus var dog fra 1719. Der var 19 huse med dampspærre i loftet og 11 huse uden. Derudover blev to typer af tagkonstruktioner undersøgt, men fordelingen var ikke ligelig (25-5). Det samme gælder huse med/uden mekanisk ventilation (6-24) og fordelingen mellem huse med mineraluld og cellulosebaseret loftisolering (27-3). Alle husene var placeret på Sjælland. Der blev desuden målt temperatur og relativ fugtighed i både boliger og tagrum samt målt udeklima.Undersøgelsen viste, at der forekom luftudveksling mellem bolig og uudnyttet, uopvarmet tagrum i begge retninger i både varme og kolde perioder. Dette gjorde sig gældende uanset, om der var en dampspærre eller ej. Som gennemsnitsbetragtning blev det fundet, at den opadgående luftoverføring var større end den nedadgående luftoverføring.På baggrund af de målte resultater, kunne der ikke konstateres en sammenhæng mellem udeluftskifte i tagrummet og absolut fugtindhold. Der kunne dog etableres en sammenhæng mellem den opadgående luftoverføring og fugttilskuddet fra boligen til tagrummet – jo højere opadrettet luftoverføring des mindre fugttilskud, dvs. forskel mellem fugtindhold i tagrummet i forhold til fugtindhold i boligen.Luftskifterne i boligerne blev målt til relativt lave værdier i forhold til bygningsreglementets krav om grundluftskifte på 0,30 l/s pr. m² opvarmet etageareal, hvilket tilnærmelsesvis svarer til 0,5h-1. Ingen af de undersøgte boliger levede op til kravet i vinterperioden, og kun fire boliger levede op til kravet i sommerperioden. Målingerne af luftskifterne i tagrummene viste en stor variation. Der blev konstateret synlig skimmel i tagrummene i tre af de undersøgte huse. Alle disse tagrum blev målt til at have relativt lave luftskifter i tagrummene.

I takt med, at der kommer stadig flere nye byggevarer på markedet, er der et stigende behov for en metode til og vejledning i, hvordan byggeriets parter kan dokumentere, at et nyt produkt eller et kendt produkt brugt på en ny måde, opfylder de krav, der er til den løsning, hvori de indgår. I denne rapport undersøges det, hvordan en sådan vejledning for især nye og uprøvede produkter kan udarbejdes. Rapporten er resultatet af et pilotprojekt, hvor formålet var at finde ud af, hvilke krav der bør stilles til en byggevare, og hvordan der kan udarbejdes en vejledning til købere og bestillere af byggevarer (herunder bygherrer, rådgivere og udførende m.fl.). Som illustration for den foreslåede metodik er der anvendt en case, hvor bygningsdelen er en let ydervæg. I casen er der sat fokus på fugtsikkerhed. Analysen peger på, at det vil være muligt at beskrive en systematisk fremgangsmåde, som skitserer de tankebaner, byggeriets parter skal igennem for at kunne opstille krav til dokumentation af en byggevares egenskaber.

​I rapporten, Drift af hvilende ejendomme - et forstudie, undersøges, hvordan driften af hvilende ejendomme foregår, og hvilken betydning de forskellige driftsformer har for bygningens stand.Der ses på, hvordan forskellige parametre spiller ind som fx bygningens funktion og placering. De forskellige enheder, der er inde over driften, har enten fokus på de byggetekniske, samfundsøkonomiske, virksomhedsøkonomiske eller energimæssige aspekter, og samarbejdet i mellem disse har stor betydning for, hvor store skader en bygning i hviledrift pådrager sig.

Existing building stock in Europe accounts for approx. 40% of the total energy consumption. Upgrading the thermal insulation of the existing buildings is an important measure to reduce heat losses through the building envelope. In some cases, increasing the thermal resistance of the construction may compromise the hygrothermal performance of the retrofitted construction. In particular, if vapour barrier is necessary for the good performance and it is practically difficult, if not even impossible, to install a well-sealed air- and vapour tight layer. To investigate the robustness of the hygrothermal performance of ventilated cold attics - with or without a vapour barrier - a monitoring campaign in a full-scale test building was set up. Also role of number of other parameters like moisture buffering capacity of the insulation material and thermal resistance was investigated. This paper presents part of this measuring campaign, which includes conditions both in the attic space and inside the insulation layer. The monitored data covers a period with two winters. The results show that it in temperate climate is practically indifferent for the hygrothermal performance of the monitored, well-ventilated attics with air-tight ceilings whether there is a vapour barrier or not and if the insulation material has moisture buffering capacity or not.

In historic masonry buildings, wood can be embedded in the walls as storey partition beams, or as supportive wall plates. Half-timbered masonry constructions, or wooden frames, e.g. combined with internal insulation, are other examples of wooden elements. Wood decaying fungi can cause serious damage to wood, which may lose mass and strength, ultimately yielding the risk of collapse. In addition, some fungal species may even be hazardous for occupants. All wood decaying fungi depend on favorable moisture and temperature conditions, although the threshold conditions may vary with various fungal species and types, and state of the wood. To predict the risk of occurrence of wood rot, several models have been developed, however most of these are based on a limited number of experiments, or very specific cases. For these reasons, the applicability of the models to other scenarios (fungal species, wood species) may not be appropriate. Furthermore, another failure mode for wood and moisture, is mold growth, which is initiated at lower moisture levels. An indication of risk of mold growth would indicate problems or risks before the initiation of wood rot. Mold growth does not deteriorate the wood, but is usually equally undesired due to health concerns of occupants. For this reason, there might be places where some mold growth would be acceptable, e.g. embedded beam ends if there is no transfer of air from the moldy area to the indoor air. Therefore, risk of rot could be important. The paper investigates models for mass loss due to wood decay and mold growth based on exposure time to favorable hygrothermal conditions. The investigation is based on inspection of wood samples (wall plates) from a full-scale experimental setup of masonry with embedded wood and monitored conditions, to which the prediction models will be applied. Monitored hygrothermal conditions were implemented in mold and wood decay models, and samples were removed from the test setup. The implemented models yielded high mold index and mass loss, whereas neither mold nor decay was observed in the physical samples. Results indicate that the implemented models, in these cases appear to overestimate the risks of mold and rot in the supportive lath behind the insulation.

Historical buildings represent cultural, historic and aesthetic value, whether preservation worthy or not. For this reason, the concept of internal insulation has been introduced as a possible energy retrofitting measure for such buildings. The application of the thermal insulation on the interior side of the wall reduces the heating energy consumption and improves the thermal comfort. But it also changes the hygrothermal conditions of that wall reducing the drying potential and leaving the original wall colder and damper when compared to pre-retrofitting. This may lead to undesired consequences like interstitial condensation, mold growth, wood rot and the general deterioration of the façade materials and components. The prediction of the hygrothermal performance of internal insulation solutions plays therefore an important role when designing successful retrofit measures. External loads, e.g. wind driven rain (WDR) and solar radiation, may vary largely depending the location and orientation and have a significant impact especially on historic buildings with porous masonry walls. This paper presents a simulation study for assessment of the hygrothermal performance of internally insulated historic masonryunder given conditions. A monitored case study made up the basis for this study that primarily focuses on the influence of orientation, indoor climate, façade color and brick type with regard to WDR, investigated through dynamic hygrothermal simulations. The results show that high loads from WDR inevitably increased the moisture content of the wall, but also certain material parameters and orientation, including solar radiation in combination with WDR play a role. Historical buildings represent cultural, historic and aesthetic value, whether preservation worthy or not. For this reason, the concept of internal insulation has been introduced as a possible energy retrofitting measure for such buildings. The application of the thermal insulation on the interior side of the wall reduces the heating energy consumption and improves the thermal comfort. But it also changes the hygrothermal conditions of that wall reducing the drying potential and leaving the original wall colder and damper when compared to pre-retrofitting. This may lead to undesired consequences like interstitial condensation, mold growth, wood rot and the general deterioration of the façade materials and components. The prediction of the hygrothermal performance of internal insulation solutions plays therefore an important role when designing successful retrofit measures. External loads, e.g. wind driven rain (WDR) and solar radiation, may vary largely depending the location and orientation and have a significant impact especially on historic buildings with porous masonry walls. This paper presents a simulation study for assessment of the hygrothermal performance of internally insulated historic masonryunder given conditions. A monitored case study made up the basis for this study that primarily focuses on the influence of orientation, indoor climate, façade color and brick type with regard to WDR, investigated through dynamic hygrothermal simulations. The results show that high loads from WDR inevitably increased the moisture content of the wall, but also certain material parameters and orientation, including solar radiation in combination with WDR play a role.

This report comprises a study of material threshold values, failure modes and related failure prediction models to enable an evaluation of adding internal insulation in historic brick buildings. Threshold values and prediction models have been investigated both within literature and through laboratory study, by for instance comparing prediction models to real field results and by testing threshold values in laboratory. The aim of this report is to find threshold values and suitable and reliable prediction models to be included in the decision guidelines and the web tool, which are the final outcomes of the RIBuild project. Failure modes included in the report are mould growth on building materials, rot and wood decay, frost damage and discoloration of facades. This report comprises a study of material threshold values, failure modes and related failure prediction models to enable an evaluation of adding internal insulation in historic brick buildings. Threshold values and prediction models have been investigated both within literature and through laboratory study, by for instance comparing prediction models to real field results and by testing threshold values in laboratory. The aim of this report is to find threshold values and suitable and reliable prediction models to be included in the decision guidelines and the web tool, which are the final outcomes of the RIBuild project. Failure modes included in the report are mould growth on building materials, rot and wood decay, frost damage and discoloration of facades.

This report comprises a study of material threshold values, failure modes and related failureprediction models to enable an evaluation of adding internal insulation in historic brick buildings.Threshold values and prediction models have been investigated both within literature and throughlaboratory study, by for instance comparing prediction models to real field results and by testingthreshold values in laboratory. The aim of this report is to find threshold values and suitable andreliable prediction models to be included in the decision guidelines and the web tool, which are thefinal outcomes of the RIBuild project. Failure modes included in the report are mould growth onbuilding materials, rot and wood decay, frost damage and discoloration of facades.

Prediction of the risk for mould growth is an important parameter for the analysis and design of the hygrothermal performance of building constructions. However, in practice the mould growth does not always follow the predicted behavior described by the mould growth models. This is often explained by uncertainty in the real conditions of exposure. In this study, laboratory experiments were designed to determine mould growth at controlled transient climate compared to growth at constant climate. The experiment included three building materials with four different surface treatments. The samples were inoculated with 8 common indoor moulds. Even after 40 weeks no growth was observed on any sample. The paper describes different hypotheses for the missing growth, and how these have been tested. Prediction of the risk for mould growth is an important parameter for the analysis and design of the hygrothermal performance of building constructions. However, in practice the mould growth does not always follow the predicted behavior described by the mould growth models. This is often explained by uncertainty in the real conditions of exposure. In this study, laboratory experiments were designed to determine mould growth at controlled transient climate compared to growth at constant climate. The experiment included three building materials with four different surface treatments. The samples were inoculated with 8 common indoor moulds. Even after 40 weeks no growth was observed on any sample. The paper describes different hypotheses for the missing growth, and how these have been tested.

This report provides an analysis and evaluation of a state-of-the-art of internal insulation materials and methods for application in historic buildings, and review on methods, tools and guidelines used as decision making tools for implementation of internal insulation in historic buildings. Historic buildings in RIBuild represent all types of protected1 and non-protected buildings built before 1945. The survey is limited to buildings with heavy walls (stone, brick, timber framing), thus excluding wooden buildings. This report provides an analysis and evaluation of a state-of-the-art of internal insulation materials and methods for application in historic buildings, and review on methods, tools and guidelines used as decision making tools for implementation of internal insulation in historic buildings. Historic buildings in RIBuild represent all types of protected1 and non-protected buildings built before 1945. The survey is limited to buildings with heavy walls (stone, brick, timber framing), thus excluding wooden buildings.

The overall scope of this Thesis "Moisture dynamics in building envelopes" has been to characterise how the various porous insulation materials investigated performed hygrothermally under conditions similar to those in a typical building envelope. As a result of the changing temperature and moisture conditions in the exterior weather and indoor climate the materials dynamically absorb and release moisture. The complexity of the impact of these conditions on the resulting moisture transport and content of the materials has been studied in this Thesis with controlled laboratory tests. The first part of the Thesis consists of a theory and literature review on the moisture storage and transport processes (Chapter 2), on the non-Fickian moisture transport (Chapter 3)and on the methods for determining the moisture properties (Chapter 4). In the second part, the conducted experimental work, results, and analysis are presented (Chapters 5-7). The major findings are discussed (Chapter 8), before the final conclusion (Chapter 9). The Appendices include the material parameters used, some additional results and the description of the simulation models.