1940s renovated for warmth

Our 1940s weatherboard home, in West Gippsland on Gunaikurnai Country, has been significantly improved to make it a less draughty, more energy-efficient cottage. After doing a blower test, which measures how much air is lost through gaps around doors, windows, and any fittings which connect with the outside such as exhaust fans and even power points, we sealed everything with a water-based sealant. Our experience could help you understand where to start if you want to stop cold air from coming in and heat from escaping.

Our house's other areas of interest are the hot water system and the retrofit double glazing. We have also changed other aspects such as insulation, added solar panels, and used verandahs and plantings to keep the house cooler in summer.

Applied to timber windows and doors, retrofitted double glazing uses two glass panels instead of one. We put a cushioning seal against the architrave to prevent air inflow or outflow from around the window. Retrofitted double glazing retains the aesthetics of older homes and improves insulation and soundproofing. Our house also has a new extension and we can share with you how these window panels can be used on all types of windows and sliding doors.

Our hot water system is also unusual in that it doesn’t use electricity or gas but is entirely heated by solar panels and a solid fuel heater. It is a passive system using thermosyphon, a method that transports water upwards without using an electric pump.

Here are some of the things we did that I can talk with you about:

Insulation

• Removed the weatherboards to put insulation and sarking in the walls
• Installed fibreglass insulation batts in the ceiling, placing wool batts on top
• Built verandahs around three sides for shading and to reduce heat loss
• Planted shelter plants to reduce wind. The house was originally surrounded on three sides by huge cypresses and pines, which funnelled the wind underneath them.
• Installed underfloor concertina foil insulation and shade cloth around the outside stumps to cut down airflow
• Retained carpets for warmth and put internal Roman blinds in the main living area.
• Reduced the gaps where cold air could enter in winter (and made the house mouse-proof at the same time)
• Installed retrofitted double glazing to all the windows, and the process sealed all window and door frames for draughts.

Heating

• Replaced the open fire with a more efficient enclosed fireplace.
• Installed a solid fuel wood heater in the extension
• Wood is sourced from a renewable wood supply planted on the property – we have planted many more trees than we will ever burn, so we consider this a sustainable energy supply.

Cooling

• Planted deciduous trees around the house for summer shading and cooling
• Have opening windows on all sides of the house for rapid cooling on hot summer evenings.

Energy use

• Installed a 2.3 kW photovoltaic grid connect system with plans to increase it to 10 kW of photovoltaics and batteries but will remain on the grid. We’ll also include an electric car charger for when we buy one
• Cut our electricity use to around 8 Kwh/day by taking hot water off electricity, installing energy saving lights and changes in behaviour
• Hot water is produced from solar panels, a wet back on the enclosed fireplace and a flue jacket on the solid fuel heater. We have a 30-year-old 360L copper storage tank in the ceiling so water movement is by passive thermocycler – no electric pumps are needed.

Draft proofing

• A blower door test and thermography report have shown how ‘leaky’ our house was and what needed fixing either by sealing gaps or increasing insulation.
• Gaps around doors, windows, architraves and skirting boards have been sealed using a water-based sealant.

Water

• All water is collected in tanks and grey water can be connected to a watering system for the garden.