Tammie Marshall Case Study


Tammie Marshall’s recently renovated four-bedroom family home, located in Balgownie, NSW, was built in the late-1970s as a three-bedroom house. After purchasing the house in June 2020, Marshall planned to renovate the property by restructuring the layout of the building, creating an open plan living space and creating additional accommodation.

A key aspect of the renovation was to add insulation for improved soundproofing. In addition, Marshall sought to replace the existing insulation materials, which were deteriorating, to help improve the thermal efficiency of the home. Knauf Insulation products were selected to help achieve the desired thermal performance and high-quality soundproofing throughout the house.


Ceiling and Walls

Construction type:

Residential - House


For the DIY home renovation, Marshall needed an insulation product that was cost-effective and quick and easy to install, while also meeting requirements for thermal quality and soundproofing. “I wanted to install ducted air-conditioning in the house, so it was important to improve the thermal quality of the home to reduce the energy cost involved,” Marshall said. “Because the home was constructed in the late 1970s, it also had an echo, and I wanted to reduce the impact of this throughout the house.”

Marshall also wanted insulation materials that were durable and would not be harmful to her family. “I work full-time as a paramedic and have attended callouts for respiratory issues because of medium- density fibreboard (MDF) and asbestos, so it’s important to me that I use products that will help my family stay healthy. By using products with less chemicals, such as Earthwool® which has no added formaldehyde, I can also minimise the risk of being exposed to chemicals while renovating myself.”


Earthwool® products were chosen to insulate the home, to meet the acoustic and thermal requirements. For the walls, Marshall installed Earthwool® SoundShield R2.7 wall batts to provide soundproofing throughout the house. During the renovation, Marshall demolished and added three walls to turn the three-bedroom home into a four-bedroom home. She added soundproofing to where the children’s rooms share adjoining walls with the living space and main bathroom. Throughout this process, Marshall used approximately 30 packs of Earthwool® SoundShield R2.7 wall batts to insulate the walls in the kitchen, laundry, hallway, lounge room, dining room, media room, and the bordering walls with the children’s bedrooms. It took Marshall only three hours to add insulation to the walls in over six rooms.

“I had an excellent experience working with the Earthwool® SoundShield R2.7 wall batts. They’re packed really tightly and fit more insulation in each pack, plus they are easy to transport. They also cut effortlessly with a knife so it’s a simple process to cut the batts to size to fit the space,” Marshall said. “I’ve used insulation in the past that was quite itchy, but I didn’t experience that at all with Earthwool® insulation. It was very soft which made it really easy to work with,” Marshall added.

In addition, Marshall installed Earthwool® R4.0 ceiling batts throughout the ceilings in the house, replacing the existing, deteriorating insulation material. The ceiling installation was completed with the assistance of tradespeople.


Earthwool® products have helped Marshall to achieve improved soundproofing throughout the house. “The quality of the sound and acoustics in the house has improved by around 50 per cent,” Marshall said. “When the doors are closed, you can’t hear the television from the kids’ bedrooms, or even hear the washing machine from the laundry, thanks to the new insulation.”

In addition, Marshall reports noticing a significant difference in the thermal quality of the home. “We had some incredibly hot days during the renovation, but I’ve hardly noticed it since we finished. I’d say we’re using the air-conditioning 60 per cent less than we were before as a result,” Marshall said.