Two Republican state lawmakers from Northern Virginia laid out a plan yesterday to give homeowners relief from soaring property assessments by capping real estate taxes.

Del. Richard H. Black (R-Loudoun) and Sen. Ken Cuccinelli (R-Fairfax), hoping to build on the defeat of a sales tax increase on the November ballot, told 100 anti-tax activists that local governments must cut spending rather than burden homeowners with higher real estate taxes for a third consecutive year.

Cuccinelli told the Northern Virginia Club for Growth that its work opposing a new regional sales tax "has resonated throughout Virginia politics. But none of you should put down your weapons."

"Local government is growing at an astonishing rate, and they're pumping up taxes like crazy," he said.

The lawmakers are the chief sponsors of two bills before the General Assembly that would limit Virginia localities to a 5 percent increase each year in property tax revenue, unless voters approve a higher increase.

Fast-growing counties such as Loudoun would be exempt from the revenue cap. They could raise real estate tax rates by the rate of their population growth plus the rate of inflation.

In a year when Virginia is struggling to close a $1.2 billion state budget deficit, a property tax cap is likely to meet with skepticism from Democrats and moderate Republicans in the legislature.

But Cuccinelli and Black raised a concern that resonates across the Washington suburbs: A red-hot real estate market has bucked the sagging economy, resulting in double-digit increases in property tax assessments. Even when the tax rate is cut -- as it was last year from $1.23 to $1.21 per $100 valuation -- many homeowners' tax bills have risen substantially.

This year's tax bills will be based on assessments that rose an average of 14 percent.

"People's incomes are not rising 14 percent a year," said Peter Ferrara of McLean, president of the Club for Growth.

Several Fairfax supervisors said at their meeting last week that a tax cap could devastate services for schoolchildren and the poor in a county that cannot tax local incomes but must rely increasingly on property tax revenue. Yesterday, board Chairman Katherine K. Hanley (D) predicted that the county would be forced to cut school spending drastically.

"Every member of the board agrees that the burden is too heavy on the residential taxpayer," Hanley said. "But the unintended consequences would be substantial." She added that businesses would get a huge tax break under the proposed bills because a cap would apply to commercial as well as residential property.

The anti-tax activists hope to take their newfound clout -- they helped elect three anti-tax state legislators, including Cuccinelli, from Fairfax last fall -- to this year's legislative elections and races for county supervisor. Republican Howard Lind of McLean announced a challenge yesterday to state Sen. Janet D. Howell (D-Fairfax).

Also yesterday, a group of Republican lawmakers from Fairfax announced a bill to increase state school spending in Virginia's wealthiest county. Under the state's current funding formula, Fairfax is penalized for its affluence, paying 76 percent of its costs per pupil. The poorest counties pay about 20 percent.

A bill sponsored by Del. David B. Albo (R-Fairfax) would require districts to cover no more than 65 percent of school spending.

"One of the reasons Fairfax property taxes are so high is that Fairfax doesn't get the state support it needs," Albo said.

Del. Richard H. Black (R-Loudoun) wants the Virginia General Assembly to impose a ceiling on increases in property tax revenue.Virginia state Sen. Ken Cuccinelli (R-Fairfax) has joined his House colleague in sponsoring a cap on property tax increases.