Hoping to ease strained relations between the federal government and building owners who rent it space, the General Services Administration will ask Congress this year to change federal leasing rules.

Richard O. Haase, commissioner of GSA's public building service, said he will ask Congress to review only those leases which cover at least 100,000 square feet. Currently, Congress must pass on all leases of $500,000 or more.

If the new threshold were put in place, Haase says about 30 percent of the building leases that now go through Congress would be exempt from that review.

GSA claims that delays are common in the congressional review process, creating ill will between the private sector and GSA. If a square-footage limit instead of a dollar amount were put in place, Haase said GSA would be able to make "better deals for the government when the opportunity arose."

"Now we are hamstrung not only by the fluctuating market, but by congressional delays which often turn a favorable situation into an unfavorable one," Haase said.

"They're not looking at the whole picture in their assessment of the problem," countered Pat Gamboney, a staff assistant on the House Public Works subcommittee on public buildings. "We in the House want them to concentrate on building new federal buildings whenever possible because it is cheaper in the long run."

As the system now works, the House subcommittee reviews all leases over the threshold amount, but the Senate only reviews GSA's proposed leasing budget on an annual basis. Sensing this pending problem last year, the Senate worked on legislation which would have boosted the review threshold to $1 million. The House, however, took no action.

Although Haase isn't opposed to the $1 million threshhold, he would prefer using a square-footage basis.

Currently, 93 of the 328 leased buildings in Washington rent at annual rates above $500,000. With the 100,000-square-foot threshhold, only 84 leases would have to go through Congress, and Haase claims that the 30 percent difference is a step in the right direction in easing strained relations.

In other cities with a major federal presence, such as New York and San Francisco, small offices of 15,000 to 50,000 square feet often are close to the congressional review level.

GSA public building planning division director David Bibb said that a decade ago Congress had to deal with fewer than a dozen leases each year because rents were much lower. "There was a good bit of inflation in the 1970s that shot up the number of leases that have to go before Congress," he said.

When the government leases space above the threshhold, it must send to Capitol Hill a "prospectus" for that lease, outlining options and explaining why the lease is needed. Currently, there are 64 of these so-called prospectuses before Congress and by the end of February, GSA plans to send up another 70 for facilities where the leases will expire in fiscal 1984.

The fate of the GSA plan and the backlog of leases is made less certain by the the House subcommittee's lack of a chairman. Rep. John G. Fary (D-Ill.), who headed the panel last year, was defeated in his bid for reelection. The Democratic members of the House Public Works Committee had a caucus Thursday to select a new subcommittee chairman, but their nominee won't be known and offered to the full committee for ratification until next Wednesday.

To avoid delays caused both by the process itself and by the empty chairmanship, GSA has adopted new contract language that allows it to renew leases with the understanding that congressional disapproval renders them void.

In most cases, Haase says, building owners accept that language because they want to seal the deal with the creditworthy federal tenants. But, in some cases, owners are wary because they fear they won't be able to obtain financing because their lenders demand a legally binding lease.

"It's an insensitivity that Congress is showing to building owners," Haase said.

Subcommittee officials would not comment on GSA's new contract language.

"They're right to the extent that someone could be hurt in the process," subcommittee staffer Gamboney said, "but the way to avoid the problem continuing is to embark on the type of careful construction program to reduce leased space that the House wants."

Gamboney cautioned that the House does not want to replace all leases with federal buildings--"that would be ridiculous," he says.

GSA has sought to lead the federal government in reducing its space holdings, most of it expected to come from leased space. In the National Capitol Region, GSA has surrendered 317,800 square feet of leased space since Jan. 1981, about two-thirds of the decline in federal space nationwide.

Ill will often develops, GSA says, when a consolidation involving two or more buildings is under way. In that case, if GSA is trying to shuffle people from two buildings into one, and the value of the lease dictates congressional approval, the landlord of the building to be vacated is at the mercy of Congress. If the prospectus is not acted on quickly, GSA has the authority to extend the lease until it can relocate federal employes--a process, Haase says, that landlords resent because they can't make plans to release the space.

"What happens if the building owner has a tenant at the time we're supposed to get out, but Congress doesn't approve the expanded lease on the other building?" Haase asks rhetorically. "We don't want to deprive them of any of their oversight responsibilities, we only want them to act expeditiously."

"He Haase has woven an example of how it is all the fault of Congress," Gamboney said. "In some cases, it would seem to me, there are other causes."