Guide to Smoothing Out Uneven Plaster

Plaster walls can look great decades or even centuries after they’ve been installed, provided that they’re well-maintained and cared for. Unsightly bumps and ridges, however, can be a real hassle to repair. Fortunately, there are a few tips that can come in handy for smoothing out uneven plaster to have them looking uniform and clean.

Use a Skim Coat

One of the more popular methods of smoothing out uneven, rough plaster walls is by applying what’s referred to as a skim coat. Essentially, an additional coat of plaster will be applied atop the original plaster walls which, since it’s still wet and malleable, can be moulded into place evenly and uniformly.

Tools and Materials Needed

Before working with paster walls, consider that you’ll want to have high-quality tools on hand to get the job done safely and efficiently. Namely, you’ll want to have:

  • A bucket with clean, cold water;
  • A finish trowel;
  • A bristle brush or paintbrush (choose natural bristles over synthetic bristles if possible);
  • A margin trowel;
  • A plaster hawk;
  • Quick set joint compound (or another type of compound depending on your walls or personal preferences).

Getting Started

Following the directions of the quick set joint compound, create a generous amount of mud and coat the plaster hawk with a thin layer, then scrape it off. This will enable the mud to stick to the hawk, even upside down, and make working with the mud a lot easier.

With hawk in one hand and trowel in the other, portion a generous amount of mud onto the trowel and apply it the wall in an upward-scooping motion followed by a downward, smoothing motion. When scraping mud onto the trowel, avoid scooping from the bottom and instead glaze over the top to ensure that you’re getting fresh, soft mud onto the trowel.

Not Over Yet

The first coat is not the finished product. This coat, sometimes called the scratch coat since it can attract bumps and scratches (although less than the rougher surface underneath), should be followed up with a finish coat which will adhere better to the wall once it sets.

Start with a gentle scraping of the trowel across the scratch coat to remove any dirt and debris that may have appeared on the surface.

Next, use the same hawk and trowel as before only this time apply a little less mud to the wall. The finished coat ought to be visibly smoother since the scratch coat will be drawing out the moisture of the freshly applied finish coat.

Finishing Touches

The finish coat will show some small imperfections that will need to be removed with moisture. Using a bristled brush, apply water across the wall liberally. Then, using a clean trowel (remove any hardened mud), scrape across the wall’s surface to fill in the imperfections. This should provide you with a glassy smooth surface once the wall sets.

Fix Your Walls Properly With We Fix Walls

Learning how to apply a skim coat or to repair plaster walls can be a valuable tool for any homeowner, but it can also lead to frustration and damaged plaster walls. Don’t risk damaging these valuable and often historic walls and instead consider contacting the friendly plaster wall experts at We Fix Walls to have the job done professionally.

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