Cracked Plaster in Your Pre-War Apartment?
Discover the difference between a simple DIY patch and professional skim coating. This guide covers everything NYC homeowners need to know to restore their walls to a flawless, long-lasting finish.
Get a Free Skim Coating EstimateThe charming plaster walls of a pre-war NYC apartment are a mark of character, but that character often comes with a network of cracks. Whether they’re fine hairline fractures or unsettling zig-zags, these imperfections can make even a beautifully decorated room look tired and neglected. The big question is: can you fix it yourself, or do you need to call in a professional?
This guide will empower you to make that decision. We’ll dive deep into why plaster cracks, how to tell a minor issue from a major one, and provide a step-by-step tutorial for a proper DIY patch. Most importantly, we’ll explain the professional process of skim coating—the ultimate solution for achieving perfectly smooth, durable walls—and help you understand when it’s the right investment for your home.
Section 1: Why Do Plaster Walls Crack?
Plaster isn’t like modern drywall. It’s a thick, rigid material applied over wooden strips called lath. Over decades, as your building settles and seasons change, this old-world system is prone to developing cracks for a few key reasons:
- Building Settling: All buildings settle over time, causing subtle shifts that rigid plaster can’t accommodate.
- Moisture & Humidity: Water from a slow leak or high humidity can weaken the plaster and cause the wooden lath to expand and contract, leading to cracks. This is a common cause of water damage.
- Vibrations: Decades of foot traffic from above and vibrations from the city can cause stress fractures.
- Foundation of the Plaster: The bond between the plaster and the lath behind it can weaken over time, a condition known as “delamination.”
Interactive Tool: Diagnose Your Crack
What does your crack look like? This can give clues to the cause.
Section 2: The Right Way to DIY a Minor Plaster Patch
For small, stable hairline cracks, a DIY repair is absolutely possible. However, simply spackling over the crack is a temporary fix that will fail within months. A proper, long-lasting patch requires reinforcing the area. You can learn more about proper preparation in our guide to prepping walls for paint.
Interactive Tool: DIY Patching Toolkit
Make sure you have the right tools for a lasting repair.
Section 3: When a DIY Patch Isn’t Enough
A DIY patch is only suitable for minor, cosmetic cracks. You need to call a professional from our Manhattan painting services team if you see any of the following:
Interactive Tool: DIY or Call a Pro?
Click the button that best describes your situation.
Section 4: The Professional Solution: Skim Coating
When walls have extensive cracking or an uneven texture, patching is no longer effective. The professional solution is skim coating. This is an intensive process where a skilled plasterer applies thin layers of joint compound over the entire wall surface, sanding between each coat. The result is a perfectly smooth, uniform, and durable surface that is stronger and more beautiful than the original plaster.
Interactive Tool: The 5 Steps of Skim Coating
Slide to see each step of our professional process.
Section 5: The Cost of Professional Skim Coating in NYC
Skim coating is a labor-intensive skill. The cost is primarily driven by the time it takes to apply multiple coats and sand them to a perfect finish. In 2025, the average cost for professional skim coating in NYC ranges from **$3.50 to $7.00 per square foot** of wall surface, depending on the condition of the walls.
Interactive Tool: Skim Coating Cost Estimator
Estimate the cost for a typical 12′ x 15′ room (approx. 432 sq ft of walls).
Section 6: A Critical Warning: Lead Paint
If your building was constructed before 1978, it is highly likely to contain lead-based paint. Sanding or scraping this paint is extremely hazardous and can release toxic lead dust into the air. According to the EPA, all work that disturbs lead paint must be performed by an EPA-certified firm following strict Renovation, Repair, and Painting (RRP) protocols.
Interactive Tool: Lead Paint Risk Assessor
When was your building built?
Section 7: Skim Coating vs. New Drywall
For severely damaged walls, you might wonder if it’s better to just cover them with new drywall. Here’s how the two approaches compare.
Interactive Tool: Skim Coating vs. New Drywall
Click to compare the two methods.
Section 8: Case Study: Brooklyn Heights Pre-War
A client’s living room walls in a Brooklyn Heights co-op were covered in a web of alligator and hairline cracks. A DIY patch would have been impossible. Our team performed a full skim coat on all walls and the ceiling before applying a final coat of paint.
Interactive Tool: Before & After Skim Coating
Drag the slider to see the difference.
Section 9: Fun Challenge: What’s That Sound?
Think you know the sounds of a renovation site? Click to play the sound, then guess what it is!
Interactive Tool: Renovation Sound Quiz
Ready for Flawless Walls?
Don’t live with cracked, unsightly walls. Our team of expert plasterers and painters can restore your pre-war apartment to its original glory. Contact us for a free, no-obligation consultation and a detailed estimate for your skim coating project.
