The FHA-VA interest rate ceiling for home mortgage hits 10 1/2 percent effective today, the highest in history.

Actions taken concurrently yesterday by the Department of Housing and Urban Development and the Veterans Administration recognized the high level of conventional mortgage rates, now ranging between 11 1/4 and 12 percent, across the country.

The higher FHA-VA rate will cost the purchaser of a home with a $50,000 mortgage an additional $18.50 a month. A 10 percent ceiling had been in effect since April. Generally, mortgage interest rates have increased more than one percent in the past year.

While purchasers using FHA-VA financing will pay 0.5 percent more interest, as a result of the rise, sellers eventually will pay fewer "points" on the sale. A point equals one percent of the mortgage loan.

The Mortgage Bankers Association applauded the rate increase, calling it necessary to meet market conditions on one hand, but saying it should have been raised to 11 percent.

The National Association of Home Builders expressed "distress" at the increase, but recognized it as being "inevitable."

The National Association of Realtors said the move reflected general monetary and fiscal conditions that have forced all mortgage and lending rates upward.

Meanwhile, House and Senate conferees are working on a new version of housing finance legislation that is expected to lower the down payment for home buyers using FHA graduated payment mortgages.