Don’t just spackle over cracks in your old plaster walls—fix them for good. Our complete guide for NYC homeowners details the professional 10-step method for a permanent patch. Learn how to diagnose different types of cracks, what tools you’ll actually need, and the crucial steps for preparation and application. We also cover when a simple patch isn’t enough and it’s time to call a pro for skim coating, plus essential safety information for dealing with potential lead paint in pre-war buildings.