Exploring the Benefits of Building Refurbishment Over New Build

Assessing a building’s sustainability for refurbishment

From an architectural standpoint, factors such as form, function, and layout are critically important along with building fabric condition and integrity.  If the building isn’t a protected structure and a refurbishment would result in small, cramped functional spaces, then architectural layout re-design considerations and wayfinding will need to be addressed. Achieving full compliance with current building regulations / standards for some older buildings can be quite challenging. 

Assessing the feasibility of fabric upgrades is also key from an energy conservation perspective. While maximising the fabric performance is a priority, it is important that fabric upgrades do not create other issues such as interstitial condensation. For protected structures, it may not be possible to upgrade some fabric elements for conservation reasons.  

From an engineering standpoint, the first thing to consider is the structural integrity of the building. Structural engineers need to evaluate whether it is safe, structurally sound and if there are issues like material corrosion or degradation, water-ingress or dampness, that could be difficult to remedy and costly to fix. 

Mechanical-electrical engineering / building services considerations will include identification of preferred ME Services-strategy, internal environmental requirements, compliance with Building Regulations / Energy Performance Directives, ESG / sustainability assessments / carbon management drivers, etc. On a practical ME design and constructability level, the potential retention and upgrade of part or all existing ME Systems is a major consideration, along with the requirements for mech-elec. service zones above ceilings, which have changed over the years. For example, if the floor plates are too tight with constrained storey heights, effective and efficient ME services refurbishment might not be feasible. 

From an energy conservation perspective, the preference will be to retrofit fossil fuel free heating solutions such as ground source or air source heat pumps. While not strictly a prerequisite, a good performing building fabric is preferable for the application of heat pumps since they operate at lower temperatures versus fossil fuel boilers.  

The intended purpose of the refurbishment is also key. For instance, a ‘light-touch’ refurbishment of a school building may not require extensive mechanical and electrical infrastructure, whereas trying to fit an operating theatre into an existing office building may present challenges related to ‘deep-retrofit’ requirements and significant floor-to-floor height constraints on ME service routing and distribution. 

New technologies and approaches for refurbishment

Advancements in technology, such as digital surveying, allow for the quick and accurate creation of background digital-models of existing buildings. In the past, people would rely on manual measurement with measuring tapes, etc., which was quite slow. Now, digital surveying and scanning technologies have made this process much more efficient, accurate and reliable. 

Technologies like 3D scanning and point cloud technology are becoming increasingly common. We’ve also started using small fibre optic cameras that can be inserted through small openings to inspect cavities within structures. When assessing existing buildings, it’s common to find that records, whether operational or as-built installation records, are often lacking, which is why many designers opt to hire third-party specialist firms to gather survey and/or operational data. 

In terms of sustainability, including material / carbon-management, the design conversation often revolves around whether it’s more sustainable to demolish a building, considering the likely material-waste involved, versus the potential carbon savings from retaining what’s already there.  

Today, there are a number of reliable sustainable design-construction-operation and carbon-management assessment tools that allow you to compare both options, helping you assess the total carbon lifetime cost and determine which approach is more beneficial over the project’s lifespan. Such assessments previously relied on multiple assumptions, whereas established proven tools now provide a standard data-driven baseline for comparison. 

In situ value testing can be very beneficial in establishing the thermal performance of existing fabrics. As well as providing a reference value for fabric upgrades, using accurate U values established by testing can reduce oversizing and thus embodied carbon.  

More modern heat pumps utilising natural refrigerants such as R290 operate at higher temperatures, making them more suitable to existing buildings particularly where fabric upgrades are not proposed or for direct replacement of fossil fuel plant.  

The role of risk assessments to evaluate potential cost benefits

Risk assessments are crucial for identifying unknown factors, such as the adequacy of existing building foundations. For example, discovering that a wall supports a roof during demolition can be quite concerning and costly. By applying appropriate risk assessment techniques, you can weigh the value for money against the carbon benefits. 

For instance, when discussing refurbishment of an older building with a potential funding institution, they might have previously viewed it as a significant risk and avoided it. However, by applying a robust risk assessment methodology to any refurbishment plans allows for better risk identification and management, along with greater cost certainty before committing to a refurbishment project. There are now tools available that enable more accurate predictions of refurbishment out-turn costs. 

Understanding carbon savings in refurbishments versus new builds

Refurbishing an existing building helps to eliminate the majority of the embodied carbon involved in constructing a new one. You also need to consider the transportation of materials to the site and the material-recovery / waste disposal associated with demolition. Existing buildings often come with pre-established infrastructure, such as roads and parking, which may not be available on a greenfield site. The total lifetime carbon assessment tool plays a significant role in this analysis, as it allows you to evaluate operational carbon savings against embodied carbon, determining whether the former offsets the latter. 

Cost savings really depend on the level and degree of refurbishment. A light refurbishment typically doesn’t cost too much, but if you’re going for a deep retrofit that involves significant changes to the building fabric, it can become quite labour-intensive and costly. Generally speaking, refurbishment should be more economical than building a new structure using modern materials. 

Have clients shown increased interest in refurbishment options in recent years?

It depends on the client. Some organisations focus almost exclusively on refurbishment due to its cost-benefit implications. Public bodies are guided by government legislation, policy and recommendations, while a significant number of developers seeking foreign direct investment (FDI) can choose to pursue LEED sustainability accreditation for their buildings to enhance their appeal, which is generally easier to achieve on new-build compared to building refurbishment project. 

In the industrial space, companies frequently re-purpose existing buildings while also expanding their wider plant-facilities with new-builds. Regular refurbishments of industrial production facilities are common, often involving the full integration of new process facilities. 

Additionally, some commercial developments in urban areas occasionally retain listed buildings within or immediately adjacent to new developments, as new-build alone may not meet the full functional or spatial requirements. 

In the healthcare sector, extensions to existing hospitals often necessitate the refurbishment of connected departmental buildings, as part of the overall development project.