How to Hang Wallpaper Over Wallpaper

Everyone wants a fresh look for their home occasionally, and homes that have wallpaper as their interior finish are no different. Installing new wallpaper is generally a straightforward project but removing the old wallpaper can be time-consuming and messy, especially if there are multiple layers of wallcovering already applied. Due to the work involved in stripping old wallpaper, many people decide to hang new wallpaper right on top of the old.
Although it may seem a viable option, ROMAN does not recommend installing new wallpaper on top of existing wallpaper. The first step in a great installation is proper wall prep. The best way to prepare any wall with existing wallcoverings is by stripping it down to it’s foundation. Experts advise against wallpaper over wallpaper installations for many reasons. The main reason is that you want your new installation to look perfect. The best way to guarantee that result is to completely remove the old wallpaper.

4 Setbacks and Dangers To Be Aware Of

1. Hanging Wallpaper over Existing Wallpaper can Negatively Impact Class A Fire Ratings.

Fire ratings are a measure of how well an individual wallcovering resists the spread of flame and smoke. Even though most wallcoverings will burn, if it has a rating of Class A,  the speed at which flame and smoke spreads is reduced. A Class A fire rating is the highest rating available.

Specifics on the Meaning of Class A

The National Fire Protection Association (NFPA) institutes standards and codes for dealing with fire prevention. NFPA tunnel tests measure how quickly a fire spreads and the progress it makes during the test. Materials with a flame spread index below 25 achieve a Class A rating.

Why a 2nd Layer Can Affect the Paper’s Fire Rating

Building codes set stringent requirements for fire safety. Installations of new wallpaper over an existing layer are unlikely to meet these safety standards.

2. Every Inch of the Existing Wall Needs To Be Inspected.

While you may be tempted to give a casual glance at the condition of the old wallpaper and determine that there are no glaring discrepancies that will keep you from covering it over, if you are not careful, this could lead to failure of the new install.  Applying new adhesive to existing wallpaper may cause the old, dried adhesive to rewet. This can cause the existing paper to bubble and peel. Additionally, the existing installation may have bubbles or other imperfections that are difficult to see. However, when new material is installed over the existing layer, these imperfections can be magnified by the new pattern.

3. Many Wallpapers are Non-Porous

Two of the most popular types of wallpaper are solid-vinyl and vinyl-coated. These materials are non-porous. In a typical installation, wallpaper adhesive can absorb into the drywall to dry. In a wallpaper over wallpaper installation, the adhesive is sealed between two non-porous layers. This can slow the drying process and cause bubbling in the new layer.

4. Summary Of Concerns 

  • Wallpaper over wallpaper installations can void a Class A fire rating
  • Existing imperfections can be highlighted with the application of new layer of material.
  • Moisture can become trapped between layers, causing bubbles.

Pro’s Recommend Removing The Old Wallpaper First.

The ideal situation is to start your new installation with a clean, dry, and properly prepared surface. To ensure your new wallcovering looks professionally installed, the experts recommend that you always remove all  layers of old wallpaper before installing the new selection. The removal process can be accomplished quickly and with relative ease by using the complete line of ROMAN removal products. Here is a list of some of the best removers:

PIRANHA™ Concentrate

This concentrate paste remover product is an excellent choice for large residential removal projects.  The gallon size makes up to 20 gallons of removal solution – enough to strip 6000 square feet of wallpaper. It is non-toxic and non-staining. Recommended for use with the Piranha scoring tool, sponge, and scraper.

PRO-466 Concentrate

If you are a painter or professional installer, this concentrate paste remover product will make fast work of removing large quantities of wallpaper. It is a concentrated mixture designed to break down stubborn paste fast. One gallon of concentrate makes 12 gallons of removal solution – enough to remove up to 3,600 square feet of wallpaper.

PRO-458 Gel Spray

Available in a handy spray bottle, PRO-458 is a gel wallpaper and paste remover designed for smaller jobs that need some extra strength to remove the paper. The gel stays wet longer, making it effective at breaking down stubborn paste. The gel also clings to the wall, helping to keep your project area clean.

Ready To Install Your New Wallpaper?

With the old wallpaper completely removed, you can now begin hanging your new wallcovering over a clean, dry, well-prepared surface. For walls that need some patching and repairs, we recommend PRO-999 Rx-35 to seal and prime the damage. For walls that are in good condition, we recommend PRO-977 Ultra Prime. When you’re ready to start hanging, check if one of our popular adhesives such as PRO-880 Ultra Clear Strippable or PRO-543 Universal is right for your project. ROMAN primers, adhesives, and removers are available at most professional paint stores and home centers. Our products are easy to use and have been proven effective over the years by homeowners and professionals alike. Contact us today for more information on where to find our products, and while you’re at our website, be sure to watch our informative videos on how to professionally complete your next project.