Q. We own a condominium apartment in the District of Columbia and we also have a parking space in the building. Recently, we received our tax bill, and it indicates that we are in a Class I category for our individual apartment, but in a Class III for our parking space. I do not understand why the parking space, which is in the same building as our apartment, is taxes at a different -- and higher -- rate. Can you explain, and can anything be done to correct this inequity?

A. In the District of Columbia, there are three different property classifications fo real estate tax purposes.

Class I is for residential property with the Homestead exemption. This exemption is avalable to persons who actually are residing in their home or condominium apartment. Cooperative apartments can fall under the Class I category if at least 50 percent of the dwelling units contained in that cooperative apartment are occupied by shareholders or members of the cooperative housing association. The tax rate is $1.22 for every $100 of the assessment.

Class II is for residential property without the Homestead exemption credit, and for apartments. The tax rate for Class II is $1.54 for every $100 of the assessemnt.

Class III is for all other property that does not fall into either Class I or Class II. This class also covers vacant lots, other than those which are next to residential property -- called abutting lots. For these vacant lots which are next to a residential property, the District will classify them the same as property they abut. The tax rate for Class III is $2.13 for every $100 of the assessment.

There is an obvious gap in the law when it comes to the parking spaces owned by condominium owners. The District has taken the position that since these are three defined categories for tax purposes, the parking space can only fix the definition of Class III, and thus is taxed at the highest rate. The District of Columbia government informally has recognized that this obviously makes no sense. Indeed, it is clearly discriminatory, insofar as the person who owns a single-family residential house with an adjacent vacant lot can use that vacant lot for parking purposes, and is taxed at the Class I rate. Condominium unit owners, who are parking in their own building, are forced to pay a higher property tax because of the interpretation by the District of Columbia government.

I can report to you that the District of Columbia government is well aware of this situation. Promises have been made by top ranking government officials to correct this inequity before the new tax year, which begins July 1, 1981. In the District of Columbia, the first half taxes are due Sept. 15, (for the half year from July 1 thru Dec. 31) and the second half taxes are due by March 30 of each year.

It is recommended that condominium unit owners write their City Council member, in care of the District Building, Washingto, D.C. It also is recommended that a separate letter be sent to Mayor Marion Barry, with a copy to the Director of Finance and Revenue, requesting that they take immmediate action to correct this obvious inequity in the tax law.

You should address the correspondence to: Carolyn L. Smith, Director, Department of Finance and Revenue, Municipal Center, 300 Indiana Avenue, NW, Washington, D.C. 20001.

It makes no sense for the condominium unit owner to be charged at a rate of $2.13 for the same kind of property that individual homeowners are paying $1.22.