How to Fix Bubbled and Cracked Paint Before Painting Walls
Many older homes have been painted so many times that the paint becomes a series of thick layers. Humidity, moisture and time have a way of causing these layers to separate and bubble, eventually leading to cracking and chipping. When this happens, removing the loose paint is a must, but the paint removal will leave the walls uneven. To restore your walls to a smooth, even surface, the damaged areas must be reworked.
This work is not hard, and the cost to do the job is minimal. When you do the repairs it will add a professional quality to your finished walls and you will feel good about the work invested.
How to Remove Old, Cracked Paint
- The first will be to clean out all the old damaged paint and plaster that has come loose.
- The second step is to resurface the damaged area. I call this floating the wall or ceiling. This sometimes requires several applications of sheetrock compound which I will also refer to as MUD.
- The last step will be to sand to a finish and apply a couple of coats of primer/ sealer.
The final outcome will depend on the amount of care put into a relatively easy job. The problem comes with having the patience to take your time and do a good job of it. Read on for detailed descriptions of each of these steps.
What You Will Need
- six-in-one tool
- mud knife or straight-edged trowel
- mixing bowl
- sheetrock joint compound (this can be bought already mixed in small to large buckets or bags or you can purchase dry joint compound and mix it yourself)
- sanding block
- shop vacuum
What About That Joint Compound?
I like to buy it in the dry form for two reasons. The first is that you mix only what you need and the remainder will last a long time as long as you do not get it wet. The second reason I would rather mix my own mud is that I can vary the consistency of the wet mud to utilize the product for different forms of application.
The dry compound also comes in different drying times. You can purchase a quick set that will begin to stiffen in as little as 20 minutes. or you can get a slow set that takes and hour to stiffen. I generally use the quickest set because I am usually in a hurry, doing repairs. The slower-setting compound is best to use when you are working on larger areas.
Step 1: Remove Loose Paint and Debris
The first thing you have to do is get rid of all the loose paint and debris that is peeling from the wall or ceiling. I like the handy "6 in one tool" for this job. It has a couple of different edges on it that you can use to gouge, score and scrape with. That is the perfect tool for opening up the bubbles and cracks.
You can use the flat edge to scrape away the loose paint and sometimes part of the plaster or sheetrock. Then you can use the pointed edge to pick in tight spots and gouge out small loose areas. This tool is also great when you come to old caulk because you can dig in and under with it and it takes care of almost everything you need to get removed. I usually take a grinder and use it to keep my "6 in one" very sharp. It makes the work go faster if the edges are honed down to a sharp blade.
When I have everything cleaned out with the 6 in one I take a sanding block and speed over everything to ensure that all loose areas are gone. This does not require serious sanding, so just speed through. You should then use a damp cloth to wipe away dust. Now the area is ready for repair.
Step 2: Refloat the Wall
Now that the bubbles and cracks in your paint are opened up and scraped clean it is time to refloat the wall. What that actually means is putting an even coat of mud on the holes so that the wall is smooth and back to an original flat surface. This is a little bit tedious but i believe anyone can do it if they take their time and are careful.
I wrote a little about the sheetrock joint compound above. I am using this because I like the way it performs. There are other products that you can purchase for the same purpose but personally, I do not like them as much as the sheetrock joint compound. You can use plaster of Paris, plaster, and there are other name brand products on the market. I know I have used everything they manufacture and I always go back to the joint compound. I always use the powdered form that you have to mix yourself. I told you why but let me expound.
Powdered joint compound will keep for a long time, like several years if you keep it dry. It is not like the premixed bucket product for a couple of reasons. They must put some kind of stabilizer in the premixed mud. It does not feel the same when you are working with it. Also, after the container is opened the product starts to dry. It first dries around the edges of the container that it comes in. No matter how hard you try to keep it covered it will begin to dry the second it makes air contact. Most repairs of any size will require more than one application.
Each time you open the container you are exposing the premixed mud to the air. Along about the third or fourth time you open the container you start to get crusty, semi-dried pieces of the joint compound falling down off the edges of your container and right into the good mud. Now when you are trying to carefully spread an even layer of the mud on to the wall and a hunk of the crusty stuff gets into the good mud, it drags a hole in your wet work area. This will make you crazy as you will have to stop and pick out the little dry hunk and then try to refloat your work. It is just too annoying for me.
The other thing about the premixed joint compound is that it is in a container that costs more to package and you will pay two or three or even four times as much for the premix. Know what are you paying for besides convenience? The answer is water. That irks me too. So the fact is all the way around you are better off to purchase the powdered compound and mix up what you need.
Step 3: Add Sheetrock Mud to the Damaged Areas
Now that you have your compound mixed you can start to float the new finish. The first application of mud will not do the job. It usually takes two, three and sometimes four applications to get it right. That is why I like the fast set formula. You can start in one area and apply the first coat and move on to other repair areas. By the time you have the entire first application in all the damaged spots, it might be dry enough to start sanding. I always make sure to put the first coat on thin not more than 1/8 of an inch thick. This is a good way to keep the sanding to a minimum.
I also like to use a fan or portable heater to finish the drying toward the end. This will help ensure that you do not hit soft compound. Pay close attention to the color of the sheetrock compound you applied. It will be gray when it goes on but then it turns white as it dries. Soft spots that are not completely dry will not be ready to sand and they will still be gray in the deepest areas. Make sure it has all turned white before you sand. You can see in the adjoining photo how the edges are starting to turn white. Make sure to watch for soft gray spots.
Sand with a fine sandpaper on a sanding block. Then mix more sheetrock compound and add another thin layer of the mud to fill deep areas and do the same as you did in the first step. Apply a thin coat on everything and wait for it to dry. The sanding should only be done to the point where the new mud is level with the existing walls. Do not sand too deep. Run your hands over the areas you have worked to feel for imperfections and also visually inspect your work.
This repair required 5 applications of sheetrock compound to get it back to the same as the original wall. It becomes a smaller and smaller amount to fill as the layers of dried mud build to form your new wall surface. It is not really hard work it just takes time. Make sure to have adequate ventilation when you are doing this kind of work. You should always wear a mask over your face to prevent as much inhalation of the sanded dust as possible. The better the quality of mask the better for your health.
I always vacuum in between sanding to help keep the dust to a minimum. The less dust, the better. I go through shop vacuums pretty regular. The fine dust is hard on the motor of the vacuum so you can imagine how hard it can be on your lungs. It is smart to use the best filters for your vacuums too. The better ones cost a little more but the benefits for you and your machine outweigh the expense.
Step 4: Seal, Prime, and Paint
The wall should feel nice and smooth and you should not be able to feel a difference in the level of the wall. If you feel a hump, you need to sand down. If you feel a dip, you need to fill with another application of sheetrock compound. When you are satisfied with the way it feels and looks, you are ready to finish with a sealer/primer. I always use Kilz brand primer because it has always done me a good job and I have been using it for over 20 years. There are other primer/sealers on the market, but Kilz is my go-to product.
I always apply two coats to the entire wall. The first coat will seal the new repair and the second coat will give you a nice even wall that is uniform in color and ready to paint. It is a good idea to wipe down the walls before you apply the primer. I do this with a dry clean cloth and I also run a vacuum over the walls and everything around the work area. The less dust, the better the paint job. It is better for your health too.
So there you have it. This work can be accomplished by anyone willing to take the time and effort and it will save you a bundle compared to hiring a professional. Good Luck on your repairs.
This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.
© 2009 C.S.Alexis