How to make a plaster ceiling medallion

How to make a plaster ceiling medallion


Would you like to have something old school cool, but don’t know what that might be for your apartment? Or maybe you have some beautiful hanging lights ordered, but the plastic cover over the wires isn’t too flattering?

No need to worry, here is a guide on making some traditional plaster ceiling designs that don’t look bad or old even today. Personally, I think that in the days when simple decoration is the most common, something like plaster ceiling medallions only makes them more interesting.

Many years ago an elaborate ceiling medallion was a very common finishing touch around chandeliers. Most ceiling medallions that you can purchase today are made of plastic.

If you want an authentic plaster medallion you can try to cast one yourself. Keep in mind that the casting technique gets better the more you practice it.

There are medallions made from cheap materials available so one made by yourself should have more quality than those. If they are some cheap soft material, they get damaged quite easily and are annoying to fix.

Buying the plaster medallion molds

Before you begin you will need to purchase some plaster medallion molds. You could try to make your own mold but that is a difficult process that is beyond the scope of this article. Here is a guide about painting plaster crafts. Here is about doing knockdown texture if you want to create unique walls to go with the ceiling.

Just to give you a picture the decorations would have to be made into a rubber-like soft and bendable mold so you might need an existing ceiling medallion to do that or make one yourself to be used to make the molds.

That being said, most ceiling medallion molds that you can purchase today are made out of plastic. You can find these available online, or even on eBay. They usually cost around thirty dollars or so as the material isn’t that expensive and you might get them even cheaper.

Plaster ceiling medallion molds can create beautiful casts

Get some casting plaster and mold spray

You will also need to obtain some casting plaster. You can purchase casting plaster from any great hobby supply store, or also online. Online shopping has really made decoration crafting easy these days as all the materials are available from around the world.

One other important item to get is a spray product called Airid Mold Spray or something that works like it. This product will cost you around five dollars for an eight-ounce spray bottle. The mold spray helps to break the surface tension of the plaster and allows the plaster to flow into every spot of the mold.

It is highly recommended for a professional look. Casting the ceiling medallion should succeed in one try, fixing decorations afterward is possible, but if it can be avoided then it should be.

Measuring and safety

If your purchased ceiling medallion mold came with instructions, it will tell you how much plaster you will need. If you don’t know, you can fill the mold with water, then dump the water into a bucket. If you mark the water level this will give you an idea as to how much plaster you will need to fill the mold.

Plaster is quite cheap though so you don’t have to think too much about making a little extra. It’s better to have a little more than less. That way you don’t have to make more if you can’t fill the mold.

When working with plaster keep in mind that it is very alkaline and can be an irritant to your eyes, skin, or respiratory tract. Always wear gloves, a mask, and some splash goggles when you’re mixing this material.

Also keep in mind that plaster will heat up as the chemical reactions take place during curing, so be careful. Read and follow all the safety instructions on the plaster package that you have purchased.

Cover your work area with some newspaper, and place the mold on top of the paper.

Making of the plaster ceiling medallion

Step 1: Completely spray the inside of the mold with the Airid Mold Spray.

Step 2: Mix up a batch of casting plaster in a bucket or a bowl. Following the instructions on the plaster container that you have purchased. Always pour the plaster into the water, never the other way. This allows the plaster to get thoroughly wet.

Mix the plaster to get it smooth, but don’t over mix it. If you mix it too much you will speed up the chemical reaction and it will set too quickly.

Step 3: Pour the plaster into the mold, and when you are finished tap the mold lightly on the work surface to remove any trapped air bubbles. Always pour slowly starting at one edge of the mold. Let the plaster flow into all the spaces of the mold.

Step 4: Let the plaster set inside the mold. You’re in no hurry to get it off, it should come off easily when it has cured. If you start removing it too soon and the plaster is soft, it will potentially ruin the medallion.

When you touch the surface it might feel hard, but it might still be soft from the inside. The plaster manufacturer info will probably have info on how long it takes it to dry by thickness.

Step 5: When the plaster has set up, you can begin to peel the plaster out of the mold. Start along the edge and work your way around towards the center. Be gentle and take your time, it is easy to damage the casting if it’s still soft somewhere.

Once you get the ceiling medallion out of the mold then you can trim up and rough edges. Let the casting sit and finish curing for several days.


Using plaster ceiling medallions molds for casting is a quick and fun way to make decorations for your house. It’s reusable so you can make as many as you want to buy one that you’d like to watch in more than one room.

You can also theme your decoration around the plaster medallion if you use a style from a certain time. These have been around for a long time so there are quite a lot of examples.

If you’re looking for more unique decorations to go with your decorations, look up this guide for making Venetian plaster walls. I think these two would go well together for some old yet new look.

You don’t have to stop there either. It’s possible to buy or make ceiling crown moulding that could make a nice finish for your room. It would be a good combination if you’re planning on plaster ceiling repair.