Crystal and Trevor Douglas of Insite Design + Construction completed the Castlemaine project in 2017.

The complete renovation lets light stream into the the Californian bungalow extension which overlooks a new kitchen garden.

"It is a north-facing home so it was quite dark and cold in there. We basically turned the front of the house into bedrooms and created a central hallway that leads down to the rear, which now is open plan with a kitchen and living area," Mrs Douglas said.

Windows set high on all four walls of the addition have brightened the space, she said.

"The extension is quite modernist and the front has been left largely intact with a bit of a face-lift."

The renovation was designed by Mrs Douglas in close consultation with the client and the build was overseen by Mr Douglas.

The couple had not planned to enter the 2019 Master Builders Victoria's excellence in housing awards but their client encouraged them to put the build up for consideration, Mrs Douglas said.

The judges were likely impressed by her partner's craftsmanship, she said.

"This is a small business and Trev is the director, but he remains on the tools and there is a lot of attention to detail. We take a lot of pride in our work."

"I think it (the award win) was also about client satisfaction. She loved every day of the experience and was very complimentary and excited."

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The renovation paves the way for the client to host cooking classes in the new addition, Mrs Douglas said.

"She has a large space now where she can set a dining table and a kitchen with a high quality stove and exhaust system," Ms Douglas said.

"The whole extension floats over the garden, where the client has put in a new landscape with wicking garden beds.

"She has her commercial biscuit company kitchen down the back of the block as well."

Nearly 40 companies and individuals won awards or commendations through the 2019 competition.

Master Builders Victoria CEO Rebecca Casson said it was an honour to acknowledge the quality of work, dedication and craftsmanship of all the winners.

"The builders and projects we honour this year are central to telling the story of Victoria, as our population growth is the quickest in the nation," she said.

The Castlemaine renovation is now in the running for an Australia-wide award at the National Excellence in Building & Construction Awards, which will be held in November.

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