Skimcoating over old wallpaper?

[Tim Townsend]

I'm a remodeling contractor who gets into a lot of different areas of work. The latest is smoothing out some walls that had been wallpapered. Some places where the wallpaper was removed also removed the toplayer of drywall paper. When I skim-coat mud over these it causes serious bubbles or bulges where the top paper had been pulled off. I assume there is an appropriate solution that I obviously do not know about. Any remedys would be greatly appreciated. Thanks in advance. Timmy T.

[Mike from NH]

Re: Skimcoating over old wallpaper?

If you into the "white meat" gypsum core you're screwed. Just re-drywall. If this is just brown paper use Zinser Gardz and seal the paper then reskim. Use a 9" x 1/2" nap paint roller and either a 10" pan knife, flat trowel or a majic trowel to smooth out.

St. Gobain Technical Fabrics makers of "fiba tape and fiba fuse" is coming out with a 36" wide roll of non-woven fibergrlass matting to inbed between the drywall or old plaster and a tight skim over top. This would act like a wall liner but would be cheaper, stronger and installs with AP mud. I will be getting a roll this week to try out. I will let you know what I thiink. It will be like this www.fibafuse.com only 36" x 150'.

[S.Joisey]

Re: Skimcoating over old wallpaper?

Mike's got it.

[Joepro0000]

Re: Skimcoating over old wallpaper?

How about you laminate 1/4" drywall over it. Compared to the amount of money your going to spend on mud and finishing labor. I recently did an interior tenant improvement in a mall, and instead of buy say 30 more sheets of rock and finishing the existing walls normally, I decided to level 5 them with 4-5 coats until they were smooth. Took alot longer. Could of hung it for $600.00 with materials vs buying 30 buckets of mud and labor for finishing.

[Mike from NH]

Re: Skimcoating over old wallpaper?

I agree with the 1/4" overlay when the existing is in bad shape. To determine if an overlay is cheaper you need to consider the outlets / plug extentions, trim and baseboard, and the added material cost. Sure taping drywall is quicker than skimming in general. But sometimes is not an option. Wall-liner / matting type products will fill the gap in options for the contractor to either do an overlay or skim (without a re-enforcement matting). Re-enforcement matting costs about .10 cents per sq. ft. So about the 40% less than drywall.

[betterdrywall]

Re: Skimcoating over old wallpaper?

What would you do ??? Tack off the fiber sheet with jt21 staple gun at the top edge to hold it in place ,then start laying on the JC? Just thinking about the best way to apply the mesh to the wall.

[Mike from NH]

Re: Skimcoating over old wallpaper?

Yes its embedded with AP. Think wall-paper or nu-wal. The benifit is AP is cheaper than any other adhesive, it fills gaps imperfections, and really bonds to the wall surface. Go www.fibafuse.com look at the sample roll. I've installed 10+ rolls of it. It really bonds / embeds excellent. The directions for the wall re-enforcement version, bascially is "painted" thinned down AP on the wall w/ a roller. Then using a pan knife you embed in into the wet AP. Let dry, and skim over top. The product is 44% stronger than AP and paper tape, when used with AP and about 60% stronger with setting muds. This is info from St. Gobain, collected during lab tests.

[Tim Townsend]

Re: Skimcoating over old wallpaper?

Thanks for the info guys. I had considered removing the rock entirely and hanging new but in this room there soffits, window returns, door trim to be removed, reinstalled etc. I'll definately get the Zinsserr Gardz and seal the paper. I don't particularly mind the skimcoating part. Next time I'll get some of the Fiba mesh wall paper to try. Thanks again and Happy Trails to everyone. Timmy T.

[Mike from NH]

Re: Skimcoating over old wallpaper?

Tim,

That wall reinforcement is not yet avaiable but look for it in a few months. Its made by St. Gobain Technical Fabrics USA. I'll report back on how I like the sample they are sending me to try out.

[betterdrywall]

Re: Skimcoating over old wallpaper?

I was orignally going to say paint on the mud with a roller and then apply the mesh. Just thinking of alternative ways to apply the mesh to the walls . Thinking less mess and cleanup . Today I have to go back and do a final sand and touchup on a home . The owners removed the wallpaper, I dont know what they did or how they did it, but it is the cleanest wallpaper removale job I've seen done by any HO. There was only one small spot where the paper actually tore apart. No paper blister anywhere. Besides having some glue on the sheetrock it looks like new. I noticed the walls in the bath area that had paper had been coated with an oil base primer before the paper was applied . Nice job to be on for sure. I'm definatly keeping the fiberfuse in mind . I remember last year a builder had his some flunkies tring to remove the WP in a dining area. Looked horrible, and took them forever.

[mudmastah]

Re: Skimcoating over old wallpaper?

Use the mat & not the glue, Nu-Wal System. The glue is way over priced & the mat is a great deal, $65.00+ for 500 sq.ft. www.spec-chem.com Peace, muddy.

www.themudmasters.com

[treyk1]

Re: Skimcoating over old wallpaper?

I just finished one of these. HO spent days removing wall paper and some of the s/r paper. it was terrible.
Seems no one around here sells Guardz so is went with Znsr oil, gold label. rolled it on very heavy...as much as the walls would take.
Quickly and carefully knocked it all down with a coarse sanding sponge (60-80 grit ?).
3 skim coats and ready for light orange peel...then realized whe wants a crow's foot. Probably could have gotten away with fewer coats.
worked very well.

[Mike from NH]

Re: Skimcoating over old wallpaper?

Steve,

Try out Fiba-Fuse tape, I can get you the techincal guy's number at St. Gobain he'll send you out a few rolls. PM and I'll send you the info. The plaster restoration product is the same thing just 36" x 150". I got my sample roll today UPS. It's only 2 lbs!

Ed-

I'm gonna call Spec-Chem for a sample roll of their product and try it out. I've seen the video, gotten a small sample seen the website ba bah blah. I know you use the 50% ES and brown bag with the jet dri and sand...But could I use AP to apply it? And once applied to the wall does it have to be skimmed over or is it primer / paint ready?

Fiba Fuse wall reinforcement fabric will be around .11 cents per sq. ft. and will come in a 450 q. ft. roll so just under $50.00

Treyk1:

Jesus Christ, If I had to apply 3 skim coats for a texture I would either have considered re-drywalling or hired someone who knew how to skim. I have applied 1 skim coat over un-primed / painted horse hair plaster (I believe its called lime puddy finish). And it really polished it up! My god 3 coats! for a texture...what gives man?

[mudmastah]

Re: Skimcoating over old wallpaper?

Mike, I have always skimmed over it, I guess if your not going for a L-5 you could probably texture over the mat itself. Again it all depends what the they (you) are looking for in the final product and how it lays down for you. My opinion you can use AP I don't see why not, it has a high glue content. Alot of my plaster reconstruction is starting out with a sow's ear so that is why I use the cocktail mud mix. With that mix I don't have to tape cracks, gaps or holes unless they are rather large. I do paper tape all inside corners so they don't re-crack. Why you ask I don't gut and re-rock. A. alot of people don't want to mess with the base & all the door & window casings, that is why. Most of the time too they don't want to open the walls up either like for wiring, insulation, plumbing, etc. I may try a area that I don't skim over just orange peel texture over the mat and see what effect that has. Good idea another time saver. I think if it is flat enough & the seems are tight you could paint over it. One more point, alot of my reconstruction I do not have to mat, I just skim over the existing surfaces. Let me know if you do something like this ok? Peace, Ed, muddy.

www.themudmasters.com

[topcoatfinishes]

Re: Skimcoating over old wallpaper?

With all due respect, you guys are making this more complicated than it needs to be.

Treat it as a paper strip job. Pump spray a stripper such as DIF or safe and simple and get the paper off. Once it is dry, prime completely with an oil primer, odorless is best. When that dries, lightly sand and then completely skim surface to a level 5 type spec. Sand smooth and apply a latex primer. When that dries, lightly sand and apply two finish coats of paint.

When you skim over paper, the water in the mud activates the glue and actually encourages it to release. Stripping is not a fun job, but would be a proper solution to this situation, and much easier than facing off with new drywall, which opens a host of other issues as far as jamb extensions etc.