Purple House Retrofit 2025

Purple House Retrofit

The Purple House was once an energy-hungry 1940s home running on gas, but it’s now a super comfortable and efficient all-electric home that rivals new builds. After a deep retrofit for thermal comfort and energy efficiency, the transformation is remarkable.

As a Home Energy & Comfort Assessor at ENFORT, I utilised my expertise to support my mother-in-law in enhancing her home. I conducted a comprehensive assessment of the original house using the Residential Efficiency Scorecard tool. Additionally, we performed variation assessments to determine which upgrade options would offer the best value for money and comfort outcomes. Our analysis estimated that an 85% reduction in heating energy requirements was possible, which we have successfully achieved in the real world.

We upgraded the insulation in the ceiling, walls, and underfloor, performed a detailed draught detection audit, and implemented extensive draught proofing. Honeycomb blinds were added to untreated windows and a door. We decommissioned the gas ducted heater and sealed all the floor vents and the return air grille.

A relatively small reverse-cycle split system in the lounge, originally for cooling, is now the primary heat source for the entire home. We use an efficient DC ceiling fan in combination with the split system to distribute and de-stratify warm air. With the installation of a heat pump hot water unit, we were able to order a “gas abolishment” for the property.

The all-electric home now boasts energy bill savings of $2000 a year and an estimated 8-year payback period. The owner’s experience of the home’s comfort is one of awe and disbelief. They take pride in not having to run the heating for extended periods in winter and never needing to use air conditioning in summer.