In this paper we construct free resolutions of a certain class of closed subvarieties of
affine space of symmetric matrices (of a given size). Our class covers the symmetric
determinantal varieties (i.e., determinantal varieties in the space of symmetric
matrices), whose resolutions were first constructed by Józefiak, Pragacz and
Weyman (1981). Our approach follows the techniques developed by Kummini,
Lakshmibai, Pramathanath and Seshadri (2015), and uses the geometry of Schubert
varieties.