The House, ignoring a veto threat from the White House, yesterday overwhelmingly passed a $27.9 billion bill reauthorizing federal housing programs and providing new incentives for low-income Americans to join the ranks of homeowners.

Adopted on a 378 to 43 vote, the measure still faces difficult conference committee negotiations with supporters of a much different Senate-passed housing bill preferred by the Bush administration.

Rep. Chalmers P. Wylie (Ohio), ranking GOP member of the Banking, Finance and Urban Affairs Committee, said that if the conference produces legislation similar to the House-passed measure, President Bush would veto it and he would urge Republicans to support the White House.

The House-passed legislation would significantly bolster the federal commitment to public housing after a decade of retrenchment. It authorizes a $6 billion increase in spending for fiscal 1991 over the current year, compared to a $3 billion increase in the Senate version.

In general, the House bill puts more emphasis on new housing construction and less emphasis on direct tenant housing assistance than was sought by the administration. And unlike the Senate, the House yesterday rejected White House efforts to bolster the financial health of the Federal Housing Administration by charging FHA-assisted home buyers more of their closing costs up front.

However, the House measure includes several initiatives sought by the administration to encourage low-income tenants to become homeowners. They include a $500 million revolving loan fund at the Department of Housing and Urban Development to subsidize interest rates for first-time home buyers, a program to aid first-time purchasers with down payments, and modified versions of administration plans to help low-income people receiving public housing assistance to purchase their units.

The House-passed bill includes a provision that ends a three-year moratorium on the conversion of low-income rental housing to market-rate units. The moratorium on the prepayment of federally subsidized mortgages by owners of low-income housing units expires in September. But as the House completed action on the bill, it added financial incentives for those owners to continue using their units for low-income housing.