He was educated in public schools of Albany, he studied architectural and free-hand drawing in New York City.
In his twenties he moved to Baltimore to begin independent practice. Later he organized the firm of Sill, Buckler & Fenhagen, and under that name designed the Federal Reserve Bank in Richmond, also the partners did a considerable amount of institutional work. A few years before his death Mr. Sill was associated with the late John Russell Pope in designing the Baltimore Museum, a project later completed in Mr. Pope's office.
It was however in the field of residential work that Mr. Sill made his greatest contribution to architecture, particularly in designing homes of the American Colonial type, and he was largely responsible for the high standards of design set in the newly developed residential section north of Baltimore.
A member of the Baltimore Chapter, A. I. A. after 1916 and elected to Institute Fellowship in 1926.