Welcome to Sealasash 

In Hobart, Melbourne, Perth and Sydney, we spend all day, every day working with windows and doors. We bring together the best technologies and materials from around the world so that you can keep the character of your home AND have modern comfort.

Our values are Responsibility, Respect, Excellence, Impact, and Cutting Edge Solutions. We will always welcome your feedback on our performance against these values from first contact through to project completion.

If you want a team who will take responsibility for their work; show respect for your home; pursue excellence in our work; make a real impact on your comfort; and use the world’s best solutions, you have come to the right place.

How we began

John Brennan

John Brennan

Founder and Director

Colm O'Shiel

Colm O'Shiel

Founder and Director

Sealasash began over a cup of coffee and a conversation between two friends, Colm and John.

Before coming to Australia, Colm had spent years in Ireland manufacturing and supplying seals to the European window and door industry.

Colm had a question for John. “Why are Australians happy to accept rattly, draughty windows? No one in Ireland would put up with the wind howling through!”

“Hang on Colm,” said John, “Australians want better windows too. At least they would, if someone could help them.”


Sealasash has restored and draught sealed thousands of timber windows around Australia.

Our projects have ranged from national- and world-heritage listed sites through to everyday homes; from individual dwellings to large blocks of apartments and major public buildings.

Thanks to that conversation, you too can experience the comfort and satisfaction of a window that performs beautifully in summer and winter, while maintaining the character of your home.

For a free, no-obligation chat about your needs, contact one of our window experts today.