Design and Building Fabric – Passive Measures
Regulatory factors (for example, UK Building Regulations and comparable design requirements) control modern building designs, which include backup values for the thermal performance of building elements (u-values) and the efficiency of HVAC and lighting. The building must, however, have an overall energy performance that can be achieved through passive design and the employment of low-carbon technology and renewables.
This is not usually as easy on older constructions. One of the primary problems in reducing energy demand is dealing with the building fabric and its constituent elements. Although building science requires that the fabric be addressed first, the economics typically don’t stack up unless you’ve previously planned an update and are simply upgrading the specification – this is normally a comfort decision or done to protect the asset, but it is not the right choice.
Both are valid parts of the business case since they protect the asset’s value and, if rented out, keep rental values stable and decrease void times. Controls and pipe insulation are typically the only cost-effective solutions when working on a stand-alone project. Plant only enters the picture if it is nearing the end of its useful life or if an upgrade is in the works.
A holistic approach to renovation is usually recommended, in which all methods that contribute to effective energy savings are evaluated simultaneously but be careful of ill-conceived attempts that cause additional issues.
If the building’s occupants are consistently exhibiting bad user behaviour, such as opening windows and utilising portable heaters, it’s typically an indication of a poorly managed structure. What steps can be taken if the appropriate environment is not provided? Normally, controls are the answer, but is the use of automated controls really necessary? The choice depends on the functionality required and whether there is a requirement to provide manual overrides.
Regulatory restrictions, as well as national and international standards, push modern building designs to incorporate energy-saving technologies and controls. Depending on the demands and funds, the intricacy of this method will vary. Building Research Establishment Environmental Assessment Method (BREEAM) and other sustainability design tools will aid in the development of new installations and refurbishment projects, but care needs to be taken that ‘green’ boxes are not simply ticked off.
User requirements, installation operation, possible maintenance concerns, user interfaces, and overall performance must all be taken into account. If any of these are incorrect, the pricey energy-saving technology will simply not operate as intended on the design table — this is part of the so-called “performance gap.”. Another pitfall might occur if the concerns of operation, maintenance, and commissioning are not addressed. A thorough examination of the installation’s intended use and a holistic approach is required; this may be accomplished utilising assessment techniques such as BREEAM-In-Use.
Installing modern technologies in existing buildings and infrastructures will also be difficult. It’s critical to make sure that the use of technology in a given installation, which is frequently a replacement for heritage, is a good use of resources. New technology, such as variable speed drives, has the potential to minimise energy usage at the point of use, but it could lead to other problems on a 40-50 year old electrical switchboard or cabling infrastructure.
Examining the entire installation is critical while performing this inspection. Another factor to examine is whether all of the essential passive measures are in place before taking active measures. Although it is not reasonable in engineering terms to replace the building’s historic cast iron central heating boiler if there is a double height single-glazed atrium losing heat from the building; economics and/or the practicalities of the fabric solution may favour the installation of a new plant and controls.