Proper substrate preparation is a prerequisite for a perfect wallpapering result. Preliminary work that is not carried out can have a lasting effect on the entire wallpapering.
In the following sections we will explain how the substrate must be.
Do old wallpapers have to be removed before wallpapering?
Always remove the old wallpaper before wallpapering. Gluing onto an existing wallpaper carries the risk of poor adhesion, seam behaviour or bubble formation or that the wallpaper below shows through.
Old wallpaper can be removed by hand with water, wallpaper solvent, a ceiling brush and a spatula. Stubborn old wallpaper that does not come off despite repeated wetting can be perforated with a hedgehog roller. Wash-resistant and scrub-resistant wallpapers can be removed better this way. If the wallpaper was applied with dispersion adhesive, often the only solution is to steam it off mechanically with a hot steam device.
Some wallpapers can be split. This means that the top layer can be removed dry and only a thin layer of paper, a so-called waste paper, remains. This serves as a base for the new wallpaper and may only be papered over if it adheres firmly to the substrate.
This can be checked by wetting the waste paper wallpaper with water in a few places and then waiting approx. 15 minutes. If no bubbles have formed by then, you can wallpaper on the existing waste paper.
What do I have to do if there are old coats of paint on the wall?
Old, non-stable or cracked coats of paint and varnish must be removed before wallpapering. This can be done by sanding or scraping.
In difficult cases, lye or paint stripping helps to remove the paint residues.
What do I have to do if there is a glue or dispersion coating on the wall?
Old coats of distemper must be thoroughly washed off with water. An addition of wallpaper solvent makes the work much easier.
Allow wipe-resistant dispersion paint coats (so-called mixed binder coats) to swell by soaking in water with the addition of wallpaper solvent and then remove. After cleaning, consolidate the substrate with water-based wallpaper primer.
What should be done if there are oil or lacquer paint coats or metal surfaces on the wall?
These surfaces do not provide a suitable substrate for wallpapering.
However, if you want to wallpaper these surfaces, it is advisable to first remove all release agents such as dust, grease or dirt from the surface and stick a maculature wallpaper (such as MAKU non-woven by A.S. Création) on it with a dispersion adhesive (e.g. Metylan Ovalit T).
In this way, you can also prepare this surface for wallpapering.
What substrate preparation do I need to do for mineral substrates?
Load-bearing mineral substrates (new plaster) should be pre-pasted with diluted wallpaper paste.
For this type of substrate, e.g. concrete surfaces, gypsum plasterboards, gypsum-based fillers, it is also advisable to prime the walls with a deep primer.
Sanding or other highly absorbent substrates must be consolidated with a deep primer.
What is the best way to treat the substrate before wallpapering?
MAKU non-woven by A.S. Création provides the perfect wallpapering base and prevents wallpaper seams from bursting.
Furthermore, MAKU non-woven serves as a tension equaliser between the substrate and the wallpaper and ensures an evenly light substrate.
Does the substrate have to be specially pre-treated for the application of non-woven/paper wallpapers?
New gypsum plaster surfaces should be primed with paste (follow manufacturer's instructions) because of the lack of absorbency.
All other substrates (concrete, gypsum boards, gypsum fibre boards, etc.) should be treated with deep primer.