Use these forms when submitting an application for new construction, alterations and additions to existing structures, tennis court, pool, driveway, patio, deck, air conditioner, electrical upgrade, propane tank, generator, oil tank installation and abandonment, etc. YOU MUST ALSO PRINT AND COMPLETE THE APPROPRIATE NASSAU COUNTY ASSESSMENT FORM FOR RESIDENTIAL, COMMERCIAL / MIXED-USE, OR PUBLIC UTILITY, available below. If the application is for a new building, alteration and/or addition to an existing building, accessory structure, etc., you must also complete the Zoning Analysis form available below.