New Drywall Joined with Old Drywall

[quinocampa]

I am remodeling a bathroom, and I only removed drywall where necessary. I have new drywall butting against existing walls and ceilings. I need advice on how to finish the joints between new and old. The existing ceiling is textured, and I'm expecially concerned about that area. Specifically, I'm assuming I have to tape the joint, so how do I do it? The existing ceiling is built up with compound and texture. Attached is a photo showing typical joined surfaces.

Thank you!

[GabeS]

You tape the seams the same way you would if it were new drywall to new drywall. You either have to scrape the texture off and skim coat the whole ceiling or try and match the texture with the new ceiling. I would scrape and make the whole thing smooth if it were me.

Make sure you put cement board in shower area walls, or waterproof membrane over sheetrock. Don't just use regular sheetrock or greenboard.
Have fun.

[frenchie]

You tape the seams the same way you would if it were new drywall to new drywall. You either have to scrape the texture off and skim coat the whole ceiling or try and match the texture with the new ceiling. I would scrape and make the whole thing smooth if it were me.

Make sure you put cement board in shower area walls, or waterproof membrane over sheetrock. Don't just use regular sheetrock or greenboard.
Have fun.

Even if it's cement board, there still needs to be a membrane of some sort, somewhere. At a minimum, plastic behind it - lapped into the tub or curb. Cement board stands up to water, but water still wicks through it.

[statjunk]

Excuse me for saying this but you're being penny wise and dollar foolish. Tear down the rest of the drywall and put up new. Anytime money you save by not tearing down you'll spend in frustration scraping or matching texture.

I also agree with what is said before. No drywall in a shower enclosure.

Tom

[jadnashua]

Personally, I prefer a smooth ceiling, but texture can be good, depending on the style of the house. If the texture has been painted, you'll not get it off easily, and best to replace the drywall. But, if it hasn't been painted, it may not be that much trouble to scrape it off. Try a spray bottle with some water in it...wet an area, let it sit for a couple of minutes, spritz it again, then use a wide putty knife and see if it scrapes off easily. You might be surprised. I did an area of about 500 sq feet in a couple of hours this way. Makes a mess on the floor, though and wear a hat!

One thing I've found that can help...it's not a texture per se, but it has some advantages in that it will cover some imperfections and has the additional benefit of adding some insulation...check out www.insuladd.com. I used it on my interior walls and, when I remodel the upstairs, will use it again, especially on the ceiling to the attic. I'll be removing the texture on the ceilings during that remodel (mostly tearing out the carpeting, putting in new wood floors, and replacing the ugly, hollow-core doors with 6-panel solid ones.

[quinocampa]

Excuse me for saying this but you're being penny wise and dollar foolish. Tear down the rest of the drywall and put up new. Anytime money you save by not tearing down you'll spend in frustration scraping or matching texture.

Tom

Perhaps I am. A contractor who added a 2nd floor for us had to match an existing ceiling texture when he cut back a floor-to-cathedral-ceiling wall to create the entrance. Certainly we wouldn't have had him tear down the entire cathedral ceiling to match 3 square feet? He did a nice job, so it stuck in my head that it was possible. The second issue is that there is blown in insulation above that ceiling. I'm not about to drop 25 cubic feet of that stuff into my bathroom, then clean it all up, then cut an access hole upstairs to add more, or spend another $100 in batting to redo it that way. I think the option I chose is manageable, especially since this all has progressed thru the winter. I don't work quickly, and the insulation issue would've been uncomfortable for me, my wife, and our infant sharing the master bedroom. Not being defensive, just showing I thought about it.

[GabeS]

I don't see the need for replacement of the drywall myself. If you are smoothing out the ceiling, that can be done very easily. If you're matching textures, it's harder. I always had little skill in matching textures. Just wasn't my thing. You need someone who knows how to do a lot of different textures, they will do a good job.

About the shower enclosure, frenchie is right about the vapor barrier over the studs and underneath the cement board. I didn't say so because I was just giving a quick pointer.

If you are going to use a waterproof membrane on the outside, then omit the vapor barrier step over the studs. You don't want a double vapor barrier, as that can trap moisture.

[statjunk]

Perhaps I am. A contractor who added a 2nd floor for us had to match an existing ceiling texture when he cut back a floor-to-cathedral-ceiling wall to create the entrance. Certainly we wouldn't have had him tear down the entire cathedral ceiling to match 3 square feet? He did a nice job, so it stuck in my head that it was possible. The second issue is that there is blown in insulation above that ceiling. I'm not about to drop 25 cubic feet of that stuff into my bathroom, then clean it all up, then cut an access hole upstairs to add more, or spend another $100 in batting to redo it that way. I think the option I chose is manageable, especially since this all has progressed thru the winter. I don't work quickly, and the insulation issue would've been uncomfortable for me, my wife, and our infant sharing the master bedroom. Not being defensive, just showing I thought about it.

Points taken. In that case I would simply double the drywall in that room. Put up a whole other layer and the finish with mud and tape. Just use longer screws to hang it.

Tom

[quinocampa]

About the shower enclosure, frenchie is right about the vapor barrier over the studs and underneath the cement board. I didn't say so because I was just giving a quick pointer.

If you are going to use a waterproof membrane on the outside, then omit the vapor barrier step over the studs. You don't want a double vapor barrier, as that can trap moisture.

Gabe, you and Frenchie speak the truth about the shower. Thanks for the advice.

[SeattleSoxFan]

Skim-coating it is another option. If you're mildly competent at taping it's pretty easy and fairly quick. The texture you have looks like it was brushed on (stippled) and may not be easy to reproduce. Ceilings aren't usually centerpoints of a room and you have more leeway on transitions than you think. It will likely be noticeable if someone examines no matter how good a job you do, but most people aren't going to be examining. To get a better transition means not doing it in a line, which means you are going to have to coat back onto the existing anyway (before retexturing).

Since matching the texture is not something you're experienced with, you might be better off skim-coating and either finishing smooth or with a consistent, new texture (more forgiving -- smooth coating a ceiling does require skill). It's like painting 1/4 of a wall. You're better off doing the whole wall. I probably wouldn't suggest it for a huge area, but most bathrooms aren't so huge.

I like it slightly better than adding additional drywall and a lot better than tearing perfectly good stuff away (ceiling load and general material waste). If you add a layer of 1/4" drywall, glue it up -- don't rely solely on nails/screws as it will sag on the ceiling. Either way, you're not talking big $$, but the skim-coat is probably cheaper.

The main caveat would be if the texture is peeling or falling off. Just another idea...

[statjunk]

Talk to any drywaller and they will tell you that skim coating over a textured surface is a no-no. It's tough. They would 9 out of 10 times want to scrape it down first then skim or lay new sheet over it.

Tom

[GabeS]

Skimming over textured surface is a piece of cake. I don't see any reason why it's a no no. I've done it a million times. The rough surface allows the compound to stick better. Just make sure the original texture is bonded well. Scrape out any loose texture. If you want a super strong bond the use plaster weld bonding agent. I don't think it's necessary though.

[statjunk]

I have never had a drywaller want to skim over textured surface. Is it possible? Yes. But I can see the difficulty with putting on a nice smooth coat.

Tom

[GabeS]

It's really not that difficult. If its a really deep stucco like finish, it may need to be scraped down a bit, but you would need to scrape a deep finish down even if you were drywalling.

It's more work to drywall. Because you still have to finish the seams. I could have the bathroom ceiling skimmed and primed in a couple of hours to a perfect finish.

[SeattleSoxFan]

When hiring a professional the $$ equation changes, and most pros are wary of smooth coat finishes because clients can be quite picky. Smooth coat is marked up quite a bit more than other finishes. Skim coating is considered a high-end finish. High-end generally equals high cost whether or not it's more work. When doing it yourself you are often already greatly discounting (and usually ignoring) your wages Otherwise you probably would be hiring it out... Though I agree skimcoating to smooth takes a lot of skill. Skim coating to close-to-smooth then texturing is far less exacting.

I've skim-coated plaster walls with stripped wallpapered many times and the surface area is far larger than a bathroom ceiling. It's really not that tough. Probably takes two coats to perfect though. First coat is rough, building up the level without going too high. Light sand then a final smooth coat. Drying time excluded this is probably only 3-4 hours total effort for the ceiling. And then cleaning the dust takes 4-5 times that

BTW: the difficulty of smooth coat is true and the high costs from pros are warranted... You can have a surface that's blemish free (i.e. "smooth" to the touch), but when you put a light at different angles (like the sun so often does) on a smooth, but not flat, surface you'll see the different planes clearly. If you texture it the reflections are more dispersed and it's quite hard to see. Often, you can just use a nappy roller and flat paint to "texture" a well-done job (even if not "smooth coat" worthy).