Integrating Mechanical Ventilation with Heat Recovery (MVHR) in Existing Commercial Buildings
As energy efficiency standards rise globally, retrofitting existing commercial buildings has become a primary strategy to reduce energy consumption, increase comfort, and lower operating costs. In Ireland, a significant portion of commercial properties were constructed before modern energy efficiency standards were established. Up until recently the solution was to demolish the building and start all over again. However, more recently the more most favourable and greener approach is to retain the existing structure and retrofit the building to bring it up to modern standards.
Retrofitting can involve many elements: from upgrading insulation and windows to optimising heating, ventilation, and air conditioning (HVAC) systems. In this context, Mechanical Ventilation with Heat Recovery (MVHR) is an effective solution that can enhance energy efficiency while improving indoor air quality. An MVHR system extracts stale indoor air, recovers the heat, and replaces it with fresh, filtered air, creating an energy-efficient cycle of ventilation that supports healthier and more comfortable indoor environments.
For many commercial buildings, traditional ventilation systems may not meet modern standards for indoor air quality. Retrofitting these systems with MVHR technology provides a way to bring these buildings up to modern standards, providing reliable ventilation that reduces both energy costs and carbon footprint.
MVHR offers several key advantages for commercial buildings:
1. Enhanced Air Quality
Indoor air quality (IAQ) is a critical factor in maintaining a healthy workspace, and MVHR systems are designed to ensure a continuous supply of fresh air, filtering out pollutants and allergens. This is especially important in commercial settings where occupants spend significant hours indoors. Good air quality supports employee well-being and productivity, while also reducing the risks associated with poor ventilation, such as respiratory issues or allergies.
2. Protecting Building Fabric
Poor ventilation can lead to a range of issues, including dampness and structural damage. MVHR systems help prevent such deterioration by carefully controlling moisture levels. This protection is particularly important in Ireland’s humid climate, as unmanaged moisture can lead to condensation and mold, which ultimately weakens the building structure over time.
3. Condensation Control
Ireland’s commercial buildings, particularly those without effective ventilation systems, often suffer from condensation issues. MVHR systems tackle this problem head-on by maintaining a balanced environment where the humidity levels are controlled, thus reducing condensation. This not only benefits the building fabric but also creates a more comfortable environment for occupants.
4. Overheating Control
MVHR systems can help limit overheating during warmer months by utilising a summer bypass function. This feature allows the system to divert warm, stale indoor air directly outside without transferring heat to the incoming fresh air, effectively “bypassing” the heat recovery process. Instead of warming the fresh incoming air, the bypass function supplies cooler outside air into the building, helping to regulate indoor temperatures and prevent overheating. This is especially effective at night time when the cooler outdoor temperatures can be used to cool the building fabric that has been heated throughout a Summer’s day.
Historic Buildings
Ireland is home to many historic commercial buildings with unique architectural heritage and historical significance. Preserving these buildings while upgrading them to meet modern energy and comfort standards presents specific challenges and opportunities. MVHR systems are especially beneficial in this context because they allow property owners to improve indoor air quality without compromising the building’s structure or appearance.
Historic buildings can be notoriously energy inefficient, often relying on outdated heating systems that contribute to high energy bills. With an MVHR system, these buildings can retain a greater amount of heat, cutting down on heating costs and carbon emissions.
While MVHR offers numerous benefits, retrofitting existing buildings, comes with its own set of challenges: MVHR systems require adequate space for ductwork and equipment, which can be challenging to install in buildings not originally designed with these systems in mind. Older commercial buildings often lack sufficient ceiling or wall cavities for ducting, making careful planning essential. In some cases, creative solutions are necessary, such as installing false ceilings or embracing the alterations and leaving the services exposed.
Maintaining the structural integrity of the original architecture is a priority. Any modifications must be planned to avoid disrupting key structural elements. Working within these constraints may require customised installation solutions, potentially increasing project costs and complexity.
SEAI Support for Energy Upgrade
When planning such a project it is important to keep in mind SEAI’s EXEED grant which provides support of up to €3,000,000. The SEAI’s EXEED Grant is a great opportunity for businesses looking to make their buildings more energy-efficient, especially for an MVHR system as part of a commercial retrofit. This grant is specifically tailored to help companies save on energy costs and reduce carbon emissions by supporting the design and implementation of highly efficient systems.
Despite challenges in retrofitting these systems into older structures, the benefits make MVHR an invaluable component of energy upgrades in the Irish commercial sector. With financial support from SEAI grants and careful planning, commercial property owners can make meaningful strides in creating more sustainable, healthier indoor environments, ensuring that Ireland’s commercial buildings remain resilient, efficient, and comfortable for years to come.
EDC - Your Global Partner For Progressive MEP Delivery
Are rising energy bills a concern, or are you aiming to create a greener, more sustainable environment in your building? At EDC, we specialise in assessing and implementing energy-efficient solutions tailored to your space. Let us help you explore sustainable retrofitting options to reduce energy use while enhancing the comfort and quality of your environment.
The Author: Peter Donnelly, Associate Director
Peter Donnelly, Associate Director at EDC, joined the team in 2023, bringing over a decade of expertise in engineering project management. With a strong background in overseeing Building Services and Renewables design from concept through to completion, Peter has become a trusted leader in delivering innovative energy solutions. His extensive experience and commitment to sustainable design are invaluable to our clients across the Dublin region, where he continuously drives forward-thinking projects that align with EDC’s vision for a sustainable future.
Email: pdonnelly@edcengineers.com