Prime minister Kevin Rudd sparked a backlash from the housing industry on Friday when he announced that the first home buyers grant he added to speculation that the government would not extend the boost beyond 30 June.

"We should all underline the fact that all good things at some stage come to an end," Rudd said in Perth on Friday.

"We've been very clear in our announcements about how long this program would last." 

The government raised the grant in October from $7000 to $21,000 for new homes and to $14,000 for existing homes, to insulate the building industry from job losses caused by the global financial crisis. 

The housing industry has repeatedly called for an extension to the grant and now the Housing Industry Association (HIA) wants the federal government to put an end to speculation.

Housing Industry Association (HIA) chief economist Harley Dale said the boost had been propping up activity in housing construction sector. 

"It's quite clear in recent months it has had a very real, positive impact on the level of building activity and therefore the level of demand for employment and building materials," he said. 

Ron Silberberg, HIA executive director, has been lobbying the government to maintain the grant for newly-built homes. 

“Our estimate is that if the government retain the $21,000 grant for new housing and reverted to a $7,000 grant we would generate an extra 15,000 jobs in the housing industry and in manufacturing and service sectors,” he said.

Nearly 30,000 people accessed the grant scheme between mid-October and January 31.