Hygrothermal Risk Evaluation for the Retrofit of a Typical Solid-walled Dwelling

There is increasing evidence that current mainstream guidance for assessing moisture risk of insulation retrofits in Ireland and the UK is unsuitable for traditional solidwalled buildings. This guidance is still based on simplified hygrothermal risk assessment methods, despite the availability of more advanced numerical software for two decades and a relevant standard in place since 2007, EN 15026. Two-dimensional versions of these software applications can extend simulation beyond one-dimensional assemblies to more complex junctions. This exploratory study makes use of one of these advanced simulation tools, aided by physical measurement, to explore hygrothermal risks of solid wall retrofits at the junction with uninsulated and insulated ground floors. A brick-faced traditional dwelling in Dublin has been selected as a case study, and four scenarios have been simulated: its original condition and three retrofit approaches. Results indicate that (a) the moisture content at the base of the wall increases in all retrofit scenarios examined, and (b) the assemblies with high vapour permeability and no membranes result in the lowest hygrothermal risk. The findings should be supported by further research and could have great relevance to guidance, specification and grant policy for energy retrofits of solid wall properties in Ireland and the UK

Managing moisture - the key to healthy internal wall insulation retrofits of solid walls

This study investigates the appropriateness of internally insulating solid walls to the Passivhaus standard. A number of variables are assessed using numerical hygrothermal simulation (under EN 15026) to check (1) associated risk of mould growth on original substrate and (2) if they result in a greater likelihood of timber decay at built-in joist ends. While air and vapour control layers (AVCLs) perform well regarding mould risk in low absorption walls, the results question their appropriateness where joist ends are built-in: when AVCLs are used, moisture levels at joist ends can potentially rise above critical thresholds, even in low absorption walls. The risk is exacerbated in climates with severe exposure to driving rain

Lessons from the Classroom – assessing the work of postgraduate students to support better hygrothermal risk assessment

The widespread adoption of transient simulation modelling tools by building design professionals to support hygrothermal risk assessment of building design specifications is a crucial component in a multi-pronged drive to reduce moisture risk in buildings. Structured upskilling is essential. Much can be learnt about the ways practitioners use such tools by reviewing the work of professional postgraduate student groups. Such review could inform the creation of a user protocol. Peer-review under the responsibility of the organizing committee of the ICMB21

Designing a generalised reward for Building Energy Management Reinforcement Learning agents

The reduction of the carbon footprint of buildings is a challenging task, partly due to the conflicting goals of maximising occupant comfort and minimising energy consumption. An intelligent management of Heating, Ventilation and Air Conditioning (HVAC) systems is creating a promising research line in which the creation of suitable algorithms could reduce energy consumption maintaining occupants' comfort. In this regard, Reinforcement Learning (RL) approaches are giving a good balance between data requirements and intelligent operations to control building systems. However, there is a gap concerning how to create a generalised reward signal that can train RL agents without delimiting the problem to a specific or controlled scenario. To tackle it, an analysis and discussion is presented about the necessary requirements for the creation of generalist rewards, with the objective of laying the foundations that allow the creation of generalist intelligent agents for building energy management.The work described in this paper was partially supported by the Basque Government under ELKARTEK project (LANTEGI4.0 KK-2020/00072)

State-of-the-art and SWOT analysis of building integrated solar envelope systems:deliverables A.1 and A.2

The present document includes a state-of-the-art review of solar envelope systems that are already on the market or that can potentially reach that stage in a short-medium timeframe. The analysis focuses on the technological integration of such solutions in the envelope and building, but non-technical issues such as aesthetic, architectural integration and customer acceptance are also tackled. The solar envelope systems are classified in: Solar harvesting systems: systems that generate electricity or heat; Solar gains control systems, controlling; Hybrid systems: combination of solar harvesting and solar gains control systems