If we want to guarantee or enhance the energy efficiency of any traditional structure, we must understand how it was intended to function rather than only aiming for the retrofit.
The energy efficiency of a structure is contingent upon its design, construction materials, location, state, and usage. We must take a comprehensive approach and comprehend each of these elements if we are to increase a building's energy efficiency. It's also critical to comprehend the distinctions between older and contemporary structures. While the latter rely on vapour barriers and air gaps to keep moisture out, the former are typically vapour permeable, meaning that moisture is allowed in and then evaporates.
Even while older structures often have solid brick walls, each property has its own unique variances. Identifying the type of building is also crucial since it allows us to evaluate its performance and the factors that influence it by knowing its design, construction, and materials.
Additionally, RdSAP suggests the necessary actions to increase energy efficiency and shows the band that could be attained if they were carried out. According to BS 7913: 2013: Guide to the Conservation of Historic Buildings, damp building fabric may be 30% less energy efficient than dry building fabric, making moisture the largest issue in older structures.Therefore, managing moisture is essential for sustainability and energy efficiency. Building pathology is crucial in this situation.
It is crucial to realize that installing impermeable components and materials could have a disastrous effect on an older building. Maintaining or restoring vapour permeability in an older building should take precedence over energy efficiency measures.
Guidance and its limitations
Vapour permeability and its overall impact on the building's hygrothermal performance should be taken into consideration when choosing which solutions to implement. Installing a single measure may have an impact on numerous other components and features of an older structure.
It is crucial to ensure that the external envelope maintains its thermal coherence, and insulation should be carefully constructed to minimize thermal bridging. This will be particularly challenging in some locations. For instance, timber joists embedded in the walls at floor-wall connections will create a thermal bridge and be vulnerable to interstitial condensation.
The ends of the joists may be at risk of rotting, nevertheless, if there is cement render or cement mortar pointing on the outside, which will prevent evaporation. The entire horizontal strip may operate as a thermal bridge and allow moisture to remain, which would have clear repercussions, if internal wall insulation is not extended through into the spaces between ceilings and floors.
There are numerous varieties of insulation goods and materials, and each one has a unique installation technique. To offer as much thermal cohesiveness as feasible, careful selection is required, particularly when only thin parts may be put, such as around window reveals.Therefore, materials may need to perform significantly better thermally for their thickness than those in other regions where thicker materials can be used.
Conclusion
While planning can and should require a lot of professional effort, Planning and specifying work to make an older building more energy efficient can and should require a lot of technical effort, but if done incorrectly, all of this can be seriously jeopardized. A strong strategy based on controlling the risks of specification non-compliance is provided by adherence to BS 7913: 2013 on project management and supervision.
Improving older buildings' energy efficiency holistically doesn't have to be difficult. Going back to the fundamentals and giving a building as much of its original performance qualities as possible is the first step. Retrofitting makes it more complicated and dangerous, and choosing materials that allow for vapour permeation is crucial in this situation.
