A widow and her two young sons are suing a building company for compensation after a four-metre wall collapsed and killed a tradesman on a Melbourne worksite.

Isabel Klanja, 29, says she is struggling to support her family because WorkSafe did not provide financial assistance on the grounds that her husband, Michael Klanja, was a subcontractor and not an employee when he died last year.

Isabel Klanja and her two sons are in desperate need. Credit:Simon Schluter

Sole traders and contractors who work for themselves are not considered employees under the workers' compensation scheme and are ineligible for WorkSafe insurance.

Ms Klanja, of Tooradin, has launched legal action seeking damages from building firm Bilic Homes, which had contracted her husband as a carpenter. The 30-year-old was killed when a brick wall collapsed during a strong gust of wind at a Bilic Homes housing project in Brighton East on June 23.