Risks of overheating in highly insulated English houses: an investigation into the design process, comfort performance and occupant behaviour

When exploring the topic of overheating in buildings, the notion is commonly applied to future overheating, as a consequence of climate change. By contrast, this thesis is concerned with present-day overheating, as it is experienced in highly insulated houses. This can be claimed to be an unintended consequence of decarbonising the built environment, which has led to high levels of insulation and airtightness in the design of new homes in the UK. However, evidence of overheating in such homes point at possible inadequacies in the design and regulatory processes leading to highly insulated homes. Such design and processes have tended to focus only on winter comfort and carbon reduction from space heating demand. With a view of addressing the design problems leading to uncomfortably warm homes, this project is devoted to finding evidence of present-day overheating in highly insulated houses. This is pursued by an in-depth, multi case study, in which a mixed method approach to research is carried out in four (different typologies of) English houses -one of which is retrofitted while the other three were built as new. In this research, these houses have undergone longitudinal environmental monitoring and user perspective data gathering, across the four seasons of the year. In addition, in-depth semi-structured interviews with architects and designers of such houses were also carried out. A number of design factors have been found to lead to overheating, mostly resulting from a design process in which the main (physical) factors, such as control of solar gain and provision of adequate ventilation, are largely overlooked. This overlooking has, in turn, originated a potential demand for cooling, especially when no other forms of adaption are provided within the houses. Monitoring has shown that HIHs can be warmer environments: overheating was found in some instances and with different degrees of severity. However, it was also found that assessments may underestimate overheating (no consideration of vulnerable occupants throughout building lifespan). In some cases, it was found that occupants were adopting adaptive behaviour. The interview with designers revealed a generalised limitation in knowledge, where the fabric first approach adopted in low-carbon design focused on winter comfort mostly. For, the role of thermal comfort (the means to deliver it through design, as well as to achieve it by the occupants) was found to be central in HIHs, as comfort is (ought to be) delivered entirely by design. In summary, then, the research findings presented in this thesis indicate that today overheating in HIHs is the result of innovation in architecture, which requires immediate feedback from real-world research to guide regulatory bodies and designers.De Montfort University British Council-funded Global Innovation Initiative Project GII10

Convergence and interoperability of BIM with passive design principles

The Passive House Planning Package (PHPP) is a parametric modelling spreadsheet for building energy performance designed initially for the certification of buildings that meet passivhaus and EnerPHit refurbishment standards. However there is also a growing use of PHPP as a design stage tool to test strategic options for new build, hybrid and refurbishment development projects. As passive design principles follow a fabric-first approach to achieve a whole-house energy performance, the concept design stages are critical to success as decisions are made regarding orientation and heat-loss parameters arising out of the building geometry. In this context, PHPP is a trusted calculation tool that is comprehensive in the scope of factors and variables included to make it one of the most scientifically superior tools available. Its practical value is reinforced from a series of comparative studies which have undertaken triangulation in design stage energy assessments and PHPP has proved to be more accurate and more cost effective in practice than other standard modelling tools and methodologies such as IES and SAP. Where building information modelling (BIM) is a combination of geometric or spatial data generally found within a 3D architectural model and a connected document management system (DMS), PHPP data has largely been limited to the latter as one of the main instances in architecture and design modeling with a bias towards non-geometric data. This has changed with the introduction of designPH as an add-on tool for SketchUp and the BIM enabling in the recent versions of SketchUp. The paper is a case study in the practical application of the designPH tool for two separate UK based domestic design projects; one new build and one refurbishment; and the practical issues of interoperability with PHPP and BIM enabled software. The case studies review (1) the potential benefits of improved accuracy and quality control that address the technical performance gap between ‘design’ and ‘as-built’ standards; (2) the requirements regarding data collection, specifically the level of definition / detail (LoD) of data needed to describe the geometry and attributes of the existing structure and input climate data; (3) the technical limitations around ICT and software skills. Recommendations are made on the value of a simplified and integrated BIM workflow to benefit passive design projects. Critically the projects explore BIM interoperability using the addition of an energy domain to the IFC schema based on the input requirements for PHPP to make it more compatible with 3D modelling packages and achieve better integration between mathematical / parametric modelling of the energy performance and the building geometry

Vulnerability and resilience in energy efficient homes: thermal response to heatwaves

During heat waves, people experience both external and internal temperatures, but they are likely to spend most of their time indoors. This situation is aggravated by the fact that the majority of excess-deaths during a heat wave occur amongst the vulnerable population. In addition, energy efficient homes can worsen this scenario since internal temperatures are prone to respond quicker to heat gains, aggravating heat stress. This paper is concerned with the vulnerability and resilience to heat waves of low carbon homes. A monitoring study of four energy efficient homes in the UK during the short heat wave experienced in 2015 is analysed. A close exploration of the variability of internal temperatures recorded with high resolution and in each room allows the areas of greatest risk to be mapped. These results are linked to occupants’ responses. The analysis shows how building characteristics and ventilation can affect thermal conditions, and how design should take this into account

Unintended consequences of sustainable architecture: Evaluating overheating risks in new dwellings

Governmental strategies to reduce heating demand from dwellings have led to a range of problems relating to ventilation and occupant comfort. In fact, growing evidence of uncomfortably warm homes has been appearing in UK consistently in the few last years. This paper discusses the overheating risk in four highly insulated homes in the UK where a mixed methods approach has been deployed to characterise areas of overheating risk, which have been found to occur with different degree of severity and different sources of risk, all related to design and occupant behaviour

Influencia de aguas pluviales en conexiones domiciliarias al sistema de desague, Sucre, en precipitaciones y propuesta de diseño, Huaraz, 2018

En la presente investigación se analizó la relación durante las precipitaciones entre las conexiones domiciliarias de desagüe pluvial y la eficiencia del sistema de alcantarillado sanitario en la red Sucre. Para ello se recopiló toda la información disponible sobre la red de alcantarillado y se completó la información faltante realizando un levantamiento topográfico y una ficha observacional a todas las viviendas aportantes a la red. Usando esta información, las fórmulas y normativa brindada en el Reglamento Nacional de Edificaciones se procedió al cálculo del caudal sanitario. Para el cálculo del caudal pluvial se usaron registros pluviográficos de una estación cercana a la zona de estudio, estos datos fueron procesados usando métodos hidrológicos. Para analizar el funcionamiento del sistema de alcantarillado sanitario durante las precipitaciones pluviales se calculó el caudal por tramos considerando el caudal sanitario y pluvial, se compararon los caudales obtenidos con la capacidad de la tubería compatibilizando con lo observado en campo. Las conexiones domiciliarias de desagüe pluvial afectan el funcionamiento del sistema de alcantarillado sanitario durante las precipitaciones pluviales en la Red Sucre, el aporte de caudal real de las conexiones de desagüe pluvial de las viviendas es 42.99 L/seg para la precipitación de análisis, comparado con el caudal máximo horario representa un 414.029%. Se diseñó una propuesta de mejora con una vida útil de 25 años usando proyecciones de intensidad de lluvia máxima, la propuesta considera el incremento de diámetros en los tramos críticos

Resilience in Latin America : exploring flooding mitigation in Bogotá (Colombia)

This paper is concerned with the implications of flooding in Bogotá (Colombia) by focusing on a specific typology of flooding -surface water flooding- resulting from excess of surface water runoff as it occurs in the Colombian capita. In particular, the paper considers some of the main alternative strategies that can be used to reduce the risk of surface water flooding and pays specific attention to the benefits of Sustainable Urban Drainages (SUDS). The suitability of SUDS in the urban context is tested through an approach focusing on the city block scale and its surfaces' characteristics. Technical and social elements of SUDS are critically analysed and accordingly, a comparative analysis is performed to test different adaptive strategies scenarios for a case study in quartier Carimagua in the inner urban area of Bogotá. Carimagua barrio has been found to be able to effectively mitigate the excess of surface water runoff, and by so to meet some of the challenges associated with climate change. On this basis, it is defended that the city block can cope with not only its own surface water runoff but also to compensate as active catchment for other parts of the city where adaptation might not be feasible

Insulin and glucose metabolism with olanzapine and a combination of olanzapine and samidorphan: Exploratory phase 1 results in healthy volunteers

A combination of olanzapine and samidorphan (OLZ/SAM) received US Food and Drug Administration approval in May 2021 for the treatment of adults with schizophrenia or bipolar I disorder. OLZ/SAM provides the efficacy of olanzapine, while mitigating olanzapine-associated weight gain. This exploratory study characterized the metabolic profile of OLZ/SAM in healthy volunteers to gain mechanistic insights. Volunteers received once-daily oral 10 mg/10 mg OLZ/SAM, 10 mg olanzapine, or placebo for 21 days. Assessments included insulin sensitivity during an oral glucose tolerance test (OGTT), hyperinsulinemic-euglycemic clamp, other measures of glucose/lipid metabolism, and adverse event (AE) monitoring. Treatment effects were estimated with analysis of covariance. In total, 60 subjects were randomized (double-blind; placebo, n = 12; olanzapine, n = 24; OLZ/SAM, n = 24). Olanzapine resulted in hyperinsulinemia and reduced insulin sensitivity during an OGTT at day 19, changes not observed with OLZ/SAM or placebo. Insulin sensitivity, measured by hyperinsulinemic-euglycemic clamp, was decreased in all treatment groups relative to baseline, but this effect was greatest with olanzapine and OLZ/SAM. Although postprandial (OGTT) glucose and fasting cholesterol concentrations were similarly increased with olanzapine or OLZ/SAM, other early metabolic effects were distinct, including post-OGTT C-peptide concentrations and aspects of energy metabolism. Forty-nine subjects (81.7%) experienced at least 1 AE, most mild or moderate in severity. OLZ/SAM appeared to mitigate some of olanzapine\u27s unfavorable postprandial metabolic effects (e.g., hyperinsulinemia, elevated C-peptide) in this exploratory study. These findings supplement the body of evidence from completed or ongoing OLZ/SAM clinical trials supporting its role in the treatment of schizophrenia and bipolar I disorder

Aerobic Exercise during Pregnancy and Presence of Fetal-Maternal Heart Rate Synchronization

It has been shown that short-term direct interaction between maternal and fetal heart rates may take place and that this interaction is affected by the rate of maternal respiration. The aim of this study was to determine the effect of maternal aerobic exercise during pregnancy on the occurrence of fetal-maternal heart rate synchronization.In 40 pregnant women at the 36th week of gestation, 21 of whom exercised regularly, we acquired 18 min. RR interval time series obtained simultaneously in the mothers and their fetuses from magnetocardiographic recordings. The time series of the two groups were examined with respect to their heart rate variability, the maternal respiratory rate and the presence of synchronization epochs as determined on the basis of synchrograms. Surrogate data were used to assess whether the occurrence of synchronization was due to chance.In the original data, we found synchronization occurred less often in pregnancies in which the mothers had exercised regularly. These subjects also displayed higher combined fetal-maternal heart rate variability and lower maternal respiratory rates. Analysis of the surrogate data showed shorter epochs of synchronization and a lack of the phase coordination found between maternal and fetal beat timing in the original data.The results suggest that fetal-maternal heart rate coupling is present but generally weak. Maternal exercise has a damping effect on its occurrence, most likely due to an increase in beat-to-beat differences, higher vagal tone and slower breathing rates

Genetic Deletion of the Nociceptin/Orphanin FQ Receptor in the Rat Confers Resilience to the Development of Drug Addiction

The nociceptin (NOP) receptor is a G-protein-coupled receptor whose natural ligand is the nociceptin/orphanin FQ (N/OFQ) peptide. Evidence from pharmacological studies suggests that the N/OFQ system is implicated in the regulation of several addiction-related phenomena, such as drug intake, withdrawal and relapse. Here, to further explore the role of NOP system in addiction, we used NOP (-/-) rats to study the motivation for cocaine, heroin and alcohol self-administration in the absence of N/OFQ function. Conditioned place preference (CPP) and saccharin (0.2% w/v) self-administration were also investigated. Results showed that NOP (-/-) rats self-administer less cocaine (0.25, 0.125 or 0.5 mg/infusion) both under a Fixed Ratio 1 and a Progressive Ratio schedule of reinforcement compared to wild type (Wt) controls. Consistently, cocaine (10 mg/kg, i.p.) was able to induce CPP in Wt but not in NOP (-/-). When NOP (-/-) rats were tested for heroin (20 μg/infusion) and ethanol (10% v/v) self-administration, they showeda significantly lower drug intake compared to Wt. Conversely, saccharin self-administration was not affected by NOP deletion, excluding the possibility of nonspecific learning deficits or generalized disruption of reward mechanisms in NOP (-/-) rats. These findings were confirmed with pharmacological experiments using two selective NOP antagonists, SB-612111 and LY2817412. Both drugs attenuated alcohol self-administration in Wt rats but not in NOP (-/-) rats. In conclusion, our results demonstrate that genetic deletion of NOP receptors confers resilience to drug abuse and support a role for NOP receptor antagonism as a potential treatment option for drug addiction.Neuropsychopharmacology accepted article preview online, 26 August 2016. doi:10.1038/npp.2016.171