In 1787 he designed the current Kalverstraat 8 for the patriotic society, but the building was stopped soon because the society was abolished. This does however show his involvement with the patriotic circles, which would later make him director of the City and Public Works Department.Boezaard, A. / Zantkuyl, H., Oud Hoorn 1993 p.80-87: Het cultuur-historisch pand Grote Oost 22 en zijn bewoners Also Viervant is believed to be the designer of the south entrance of the Oude Kerk in Amsterdam.
