When I was younger I remember my mother using pre-pasted wallpaper in our home, but in additional to the pre-pasted she still always used a mixture of wallpaper paste with it. When I grew up and got married we didn't have wallpaper in our first few homes, but one of our apartments came complete with dark blue pin-dot wallpaper and blue 'country goose' wallpaper border. Oh, that had to go! And quickly! So I ripped it down and ventured to apply my first wallpaper.
I bought pre-pasted and put it up and sure enough, seams didn't stick as they should, corners sometimes peeled down a bit and in the end, it shrunk when it dried so there were gaps between the seams. Later I replaced the wallpaper in a bathroom and in our first home added borders in 2 bathrooms. I found that the quality of the pre-pasted paper and borders varied. Some were wonderful and needed no additional paste. Others were awful and curled and fell down.
When we moved into our current home I purchased $120 worth of wallpaper and border for her room. It was to be done in pink and purple with a frog/princess border and it came pre-pasted. Assuming the higher priced paper and border would be good quality I did not use additional paste and it seemed to go up easily and beautifully! I finished her room and left to go downstairs. When I returned to her bedroom 2 hours later I met a disaster. 80% of the wallpaper was down on the floor! I was so angry I found myself putting it up in a huff with a stapler and elmers glue. After my temper had cooled I ended up taking it all down. The quality of the paper was so bad that once the walls had dried completely you couldn't even see nor feel any wallpaper paste residue or discolor. It looked as if nothing had been done to her walls at all (and obviously the paper came right off with no treatment or ripping!).
That's when I learned. No matter what I will always use extra wall paper paste in the future. What a waste of time and money! Never again.
Homemade wallpaper paste
1 cup cornstarch
1 scant cup sugar (more than ¾, but less then 1)
2 teaspoons powdered alum
Mix above together with just enough water to dissolve the ingredients. Then add 6 quarts of rolling boiling water, stirring constantly. This paste can be stored in an air-tight container for some time. (Mrs. Leota Gregory, Robbins, Iowa)