Enhancing Energy Efficiency: A Case Study by ARKATA
Key Insights
Heating and cooling requirements reduced by up to 60%.
Yearly heating and cooling costs slashed by up to 86%.
Overall annual energy costs reduced by 50%.
The family’s resilience, comfort and health within the home increased.
Image Source: AAA Drafting 3D Perspective
When this family began planning their dream home, they knew they needed an expert to help them make it as energy efficient as possible without breaking the bank. That’s where ARKATA stepped in.
We embarked on the ARKATA way as the client’s sketch designs were being finalised. By engaging with us early, the family was ensuring their home would be the energy efficient and adaptable home they envisioned.
The Mission
Three core outcomes guided our collaboration:
1. Recommend a balanced home specification list that achieves the highest energy efficiency outcomes within the overall budget
2. Have a clear understanding of the most cost-effective heating and cooling solution. Particularly around the possible investment into a hydronic in-slab heating system.
3. Provide a clear and simple way to understand each enhancement and their impact on the home’s performance.
Starting Point: Energy Baseline
Our first task was to audit the home’s current energy efficiency. We were delighted to find that the design had already adopted a number of smart, passive solar design features such as awareness of orientation, northern glazing, taking advantage of crossflow ventilation and consideration of window specification and performance.
The house began at a robust 6.1-star energy rating and required more cooling than heating throughout the year.
Key Findings & Recommendations
Through our iterative investigation of various aspects of the design and construction, we identified several opportunities for enhancing the home’s energy performance.
1. External Wall Insulation: Upgrading to R4.0 insulation significantly improved the homes thermal resistance.
a. Bonus: Ventilated cavities augmented the wall system’s effectiveness
2. Internal Wall Insulation: R2.0 insulation in key areas had a noticeable effect on thermal regulation, slashing energy costs.
3. Slab Insulation: Insulating the slab edges cut down on heat loss.
4. Ceiling Insulation: R6.0 insulation worked in harmony with ProClima membranes, enhancing internal temperature stability.
5. Ceiling Fans: Installed in living areas and bedrooms, these reduced cooling loads and maximised the ability to purge summer heat.
Incorporating these upgrades increased the energy rating up to 8.2 stars and cut both heating and cooling loads by 60%.
Figure 1: Total heating load reductions (6.1 Stars to 8.2 Stars)
Figure 2: Total cooling load reductions (6.1 Stars to 8.2 Stars)
Human-Centred Outcomes
We found that the home’s cooling needs slightly outpaced its heating needs. This crucial insight led us to discard the idea of a hydronic in-slab heating system as it was not cost-effective for this home.
By comparing Figure 3 and 4, we can see more energy is required during summer months to bring the home into comfortable temperature ranges. Whereas in winter, the home naturally maintains comfortable temperatures, ultimately reducing heating requirements.
With more consistent internal temperatures, the home is made healthier and more comfortable for the family all year round.
Figure 3: Internal temperatures during a cold week in winter in the Living and Kitchen
Figure 4: Internal temperatures during a hot week in summer in the Living and Kitchen
Because of this insight, we advocated for high-efficiency reverse cycle split systems. These systems not only fulfill the home’s cooling needs but will also be able to provide ample heating when necessary. This strategy also aligns the heating and cooling requirements with the on-site renewable energy opportunities available.
Future Savings
Our collaborative efforts resulted in slashing annual heating and cooling costs by a staggering 86% and overall energy costs by up to 50%.
The family not only achieved their energy efficiency goals, but also freed up budget for other aspects of their dream home by better understanding their homes performance and the effectiveness of a high efficiency reverse cycle split system approach.
By enhancing the home’s energy efficiency within budget constraints and aligning the heating and cooling strategy with the on-site renewable energy opportunities available, the family is future-proofed, adaptable, and ready to live their desired lifestyle.
Figure 5: Comparison of the annual cost of heating and cooling
(6.1 Star Gas Equivalent vs 8.2 Star In-Slab vs 8.2 Star Split Systems)
The Client’s Verdict
The homeowners couldn’t have been happier.
We cannot rate Ben from ARKATA highly enough. From initial contact through to completion of our energy assessment, Ben was super approachable, professional and a great communicator. Every decision was backed by thorough analysis, which enhanced our initial 6.1 star home design to an 8.2 star home - a terrific result which gave us confidence in our design.
We were impressed with the detail in the report & the videos that accompanied it. Ben used language that we could easily understand & was quick to clarify any questions. We highly recommend using ARKATA as it has helped us to prioritise aspects of our build that will make it the most energy efficient & we consider him an important part of our design team!
Michael & Kara, Homeowners
Ready to take the next step in making your home or project as energy efficient as possible?
The way forward starts here…
1. Fill out our contact us form for a tailored consultation: Contact Us
2. Prefer to chat? Drop us an email at ben@arkata.au or call directly on 0431 922 265.
Let’s collaborate to enhance your project with the benefits of energy efficiency!