Wallpaper glue is essentially what is known as wallpaper paste. It is what is put on wallpaper to get it to stick to the walls. When you take down wallpaper to paint the walls, you might wonder if you got all the wallpaper glue off but how would you know if you did? And what happens if you do not?
How to Tell if Wallpaper Glue is Removed
To find out if you have removed all the wallpaper glue from the walls is a simple process. Spray some water on the walls and let it soak in. When you run your hand over the damp walls, it should feel smooth. It still has glue on it if the wall feels sticky or slimy.
If it still has wallpaper glue, you will have to go through the entire process again to remove the glue in the places it still feels slick or slimy. It could be an entire wall or just various patches on the wall.
How to Remove Wallpaper Glue
When you are removing wallpaper so you can paint the walls, there will often be a sticky residue that is left behind on the walls. It can be difficult to remove but it is necessary to make the wall feel smooth, not slick or slimy.
Although removing wallpaper glue only requires a few simple tools and techniques, it is a time-consuming task. Most of the tools you need you can find around the house or at the local hardware store. Mix the cleaning solution in small batches to make sure the water remains hot.
Things you will need:
- Drop cloths
- Liquid dishwashing soap
- Clean towels and sponges
- Spray bottle
- Drywall knife or wallpaper scraper
Step 1: Move everything away from the walls and put drop cloths on the floor. This is to protect them from water damage. To avoid electrical danger, cover outlets, and move electronics.
When handling wallpaper with glue on them wear disposable gloves. Have a trashcan nearby to put the wallpaper in.
Step 2: Mix a small batch of solution using hot water and a few drops of liquid dishwashing soap and a big teaspoon of baking soda in a bucket. Soak a sponge in the solution. Gently rub it into a section of the wall. As the wallpaper softens, wipe away the glue residue as you pull the wallpaper off the wall.
If the wallpaper does not come off easily, you can gently use the scraper to remove it. Rinse the soap from the walls. Dry the surface with a clean towel. Before drying, feel the walls to see if they are smooth. If not, repeat this step until the wall feels smooth.
Step 3: If you are still having trouble removing the wallpaper glue using the above solution, you can mix one cup of white vinegar and a gallon of hot water in a clean bucket. Soak a sponge in the mixture and ring out the excess liquid. The sponge should be damp but not dripping.
Rub the sponge gently over the areas that still have wallpaper glue residue. Allow the mixture to soak in and sit on the areas for several minutes.
Step 4: Using the scraper, gently scrape away any remaining wallpaper glue residue. Repeat the soaking and scraping until all the wallpaper glue residue is removed.
- You can also pour the solution into a spray bottle and use it for high areas. This will help to prevent spills and drips.
- For tough wallpaper glue residue, mix four tablespoons of fabric softener or one tablespoon of baking soda in a spray bottle with hot water. Use this in place of the water-vinegar mix.
- Only put the solution on a small section at a time. The size of the area must be what you can strip in several minutes.
- Do not oversaturate the drywall and damage the paper facing on the drywall underneath.
Warnings: One thing to note is that sometimes old wallpaper glue can contain toxic fungicides. Dispose of the residue accordingly and keep it away from pets and children.
Painting Over Wallpaper Glue: the Dangers
Most people, when they remove wallpaper, are going to paint the walls. The wallpaper glue needs to be removed because if not, the paint will not stick to the walls. It will peel right off. When all the glue residue is removed, you will have a professional paint finish that will last for years.
Mixing wallpaper glue with latex paint: Most of the glue that was used on wallpaper was water-based and when repainting the wall, a water-based paint will normally be used. People use water-based paint because it is easy to clean up, environmentally safe, and has a low odor.
If you mix the two, the glue left on the wall will absorb the water from the paint. This in turn will reactivate the wallpaper glue. When this happens, this is what will cause your paint to never adhere totally to the wall. That is why it will peel off and look unprofessional.
As time goes by, you would start to see chipping and cracking in the paint. You will be able to brush it off the wall with your hand or anything that touches the wall.
Tips to Make Painting Over Wallpaper Glue Easier
If you have spent a considerable amount of time trying to remove wallpaper glue from walls but still have that sticky, slimy feeling, you can leave it on but use an oil-based primer. Do this before you paint your walls and you will not have to worry if there is wallpaper glue still on the walls.
The oil-based primer will help to seal the wallpaper glue so that you will not have any issues with using water-based paint. The water in the glue will not reactivate if you use an oil-based primer first. The reason is that oil cannot mix with water.
Even if you feel you have all the wallpaper paste off, it is a good idea to use an oil-based primer. This will ensure that if you accidentally missed some glue, the water-based paint will still adhere to the wall.
If you follow these instructions, you should have no trouble getting the wallpaper and the glue residue off the wall. It will just take time and is not a job you can get done quickly. If the wallpaper has been on the walls for a long time, you may have some stubborn glue that will require you to use a commercial wallpaper stripper.
Once you have the walls smooth with no wallpaper glue residue, you need to let the walls dry for at least 24 hours before you do anything to them. Just remember, the walls need to feel smooth and if not, the wallpaper glue is still there. You will have to repeat the cleaning steps.
You can also rent a steamer to help make removing wallpaper glue easier. There are also professionals that remove wallpaper and will make sure no glue is left behind. To reiterate, feel the walls and if smooth, the wallpaper glue is gone but if slick and slimy, it is not.
Make sure that when removing wallpaper glue from walls that you take your time as it is a tedious job.