This paper reviews empirical data from evaluations of the influence of residential energy efficiency retrofits on indoor environmental quality conditions and self-reported thermal comfort and health. Data were extracted from 36 studies described in 44 papers plus two reports. Nearly all reviewed studies were performed in Europe or United States. Most studies evaluated retrofits of homes with low-income occupants. Indoor radon and formaldehyde concentrations tended to increase after retrofits that did not add whole-house mechanical ventilation.

An overview of climate change mitigation opportunities in the world's buildings is presented, based on the key building-specific findings of the Fourth Assessment Report from the Intergovernmental Panel of Climate Change. Buildings and the building stock can play a major role in mitigating climate change in the short- to medium-term, since substantial reductions in CO2 emissions from their energy use can be achieved over the coming years.

The existing residential building stock accounts for a substantial portion of worldwide energy consumption and greenhouse emissions. Improvements to the thermal performance of existing buildings is a vital activity to mitigate climate change, and often has additional benefits in the form of improved comfort, health and well-being for occupants. Despite the extensive body of literature in this area, it remains a difficult task to assess the performance of retrofit packages in occupied residential buildings.

Many recent major studies, including the IPCC’s Fourth Assessment Report, have attested that energy efficiency is humanity’s prime option to combat climate change in the short- to mid-term. The potential to avoid CO2 emissions cost-effectively has been reported to be significant through efficiency policies. However, the review of global research findings on the quantification of cost-effectiveness of opportunities through improved efficiency has highlighted that there is a major shortcoming in the vast majority of such calculations.

Today, buildings still account for almost half of the global energy consumption and carbon emission. This highlights the necessity to increase energy efficiency requirements worldwide in a common effort to reduce the construction sector's impacts on the environment. The current energy policies are driving toward a design that relies on airtight and highly insulated envelopes. As a consequence, energy efficient houses are found to have insufficient indoor air change rates, impacting on the indoor air quality and resulting in higher latent loads.

This paper aims to review the achievements of previous studies addressing the capability of atriums for providing adequate levels of daylight and visual comfort. This study also performs several simulations using Radiance IES-VE software predominantly with the target to support the literature review results. The analysis discusses ways of daylight transmission through different atrium structures.