View Full Version : swelled tape seams

02-16-2004, 05:42 PM
I'd love some input on how to fix bad looking taping seams. These seams are both on butts and tapered edges. Especially in the ceiling planes you see the seam kind of bulged all the way down with a center line which you can sometimes feel, sometimes not. On walls you can feel the bulged area with almost a discernable ridge at the line. I think this line probably has to do with the mud sagging the tape out but not blistering it-the tape is not bubbled or cracked. The walls are spray painted. I've tried feathering these out, but have had only limited results. It tends to telegraph on the bulged area so in trying to keep it as flat as possible the shadow line still shows. Any suggestions would be appreciated.

Mike S.
02-16-2004, 09:53 PM

It sounds like the ridge in the middle is the fold like in the paper. If you can see or feel this there is not enough of a top coat.

Try putting less mud under the paper tape, and make sure the mud is wet enough to stick. Before you top coat it try to squegee out the excess mud with a knife held at an angle. Then bed the tape using a bedding knife (I don't remember what it is called really), it looks like a steel concrete float about 10 inches wide and 4 inches across. The difference is that it has a curve or bow in it. This tool really covers the tape fast an effectively.

Good luck,

02-17-2004, 07:22 AM
I think you left to much mud in the middle of the tapered seams and on the butts, well they are always ridged or bulges, it's just the nature of the elongated curve on the butt.

When you do the tapered seams next time, make sure you don't leave too much mud in the middle - perhaps your knives are curved too much. You can feather them out and as you said, the bulge will still be there but maybe not as promment.

02-17-2004, 12:24 PM
I think these may be compression ridges instead.

02-17-2004, 05:23 PM
What are compression ridges?

02-17-2004, 07:01 PM
Sometimes if there is a lot of settling of weight from above and the drywall is butted tight to each other and the floor, you get a skinny bulge about 1/8 inch thick along the horizontal seam.

I have seen it in a condo where there was a lot of water pooled on the roof.



02-18-2004, 06:06 AM
How was the weather when you finished the sheetrock?sometimes moister will make the center of the tape bulge,(see the USG handbook or website,it talks about this)..........Was the tape put on right???There is a front and back...The ridge of the tape always go toward the wall

02-18-2004, 01:28 PM

Compression ridging is only evident on high walls, mostly over 10 feet such as in high foyers and cathedral ceilings. Wood shrinks on its width not on the length as the tree rings compress. What shrinks mostly in between floors is the wood laid flat. Compression ridging is not evident on ceilings and that's what Mike has.
Would be goopd to know hgow hopw the walls are but then the bulging on the ceilings - how is that explained except for perhaps high moisture.

mike wizner
02-18-2004, 06:26 PM
ok- here's the my situation. I'm one of those warranty guys for a production builder. The builder I work for has me go to houses primarily at 2 points. The first is upon imment closing. I touch up, final punch,etc. And I see alot of these houses taped by various subs with pretty visible tape bulges and also these lines-which are definitely coming from the center of tape. I know this because on several occassions I have dug the tape out and checked the joint of the drywall. The other assignment and more problematic visit is after one year. These customers routinely point out tape seams as a defect. I believe most of them have been there from day 1. Yesterday I tried with I think some success 2 heavy coats over these seams. (a huge amount of work; also dry times and paint) My employer does not want me re-taping these houses. What do you think is acceptable craftsmanship? What is a builder grade industry standard? I've taken the position on the budged visible seam as yeah I see it and yes its ugly but.., however the ones with these sagging lines ouch-gotta fix? What do you think? By the way the job description is more about nail pops and cracks- not cosmetics.

Ed Miller
02-19-2004, 05:36 AM
Sounds to me that the tape lines you see are from the gaps not being prefilled? We had one just the other day on a butt joint. They get in a hurry, there is a slight gap, it is not prefilled, they run the banjo or bazooka over it. It looks good through the tape, fill and finish coats, still good on sanding, they when texture is applied, you get this stright line. Somtimes they will go away when dry, most times not. I go to a vet supply house, get a large gauge needle and syringe than inject mud into the crack, smooth out with my finger, the line disappears. If that is what we are talking about. Good luck, Ed.

02-19-2004, 06:02 PM

What type of climate are you in> $ seasons or California Heaven? Three factors contribute to poor finishing work:

1) Wood shrinkage
2) Humidity
3) Cold

Make that 4) Poor workmanshsip.

Seams should not have what you describe, but on butts is more prevalent because when the boards are tight as the stud shrinks it compresses the butt boards you get that line what is called 'ridging'.
I can give a whole thesis on what may go wrong, but you would have to first tell me the climate and how the subs rock and finish.

All sheetock should have a space between it - it's in the handbook but not many do..that's just one of the possible causes.

02-19-2004, 07:16 PM
Thanks for all these ideas. Upstate NY 4 seasons of medium to extreme weather. They are butting the rock and I've never heard or seen anyone do it differently. In fact won't the tape have a tendency to bulge out if there's mud between the sheets?

02-20-2004, 07:32 PM

The tape will not bulge out if there is mud behind it and there should be. You cannot have the tape float in air and expect it to stay firm. Say you had an 1/2" diameter hole on the rock, if you don't put mud behind it the repair will not work. The same holds true for seams.

Upstate NY - didn't you have minus 30 a few weeks ago. Those winters and the lack of proper heating I think is the problem. From October to April you should have constant above 55 heat; that is, the rock should be warmed for 2 days prior to hanging and thereafter while finishing and forever thereafter, the temp should be above 55. If you don't, you will have problems and I bet this is your problem since the finishers use joint compound. I would venture to guarantee that if the finishers used a setting cocmpound to tape and 2nd coat and the final coat with a joint compound, your problem would cease to exist. This is for walls under 10 feet - above 10 feet you may run into compression problems.

Yes, most feel that rock should be tight against eachother, but when the wood shrinks that's when ridging and compression occur.

02-20-2004, 07:42 PM

Some fella by the name of Myron Fergusson wrote this so please check out the link and it happened in upstate New York so it's in your neck of the woods!

Cold Weater & Drywall (http://www.wconline.com/CDA/ArticleInformation/features/BNP__Features__Item/0,3299,118996,00.html)

02-21-2004, 09:18 AM
Steve, guilty as charged- you hit the nail on the head. And thanks for the link to Myron's article. That's definately the cause, although we don't routinely operate that way, sometimes scheduling and weather conflict. At least this builder backs up their product with a one year warranty period.

02-21-2004, 05:17 PM

Ask the builder if he will contemplate having the finishers use a seeting compound to tape and 2nd coat with. It will save a lot of your problems and save prestige and money down the road.

Get some Durabond 90 or Easy-Sand and put it on the left sleeve of a shirt and on the right sleeve use joint compound. Let it dry and then give it to the builder to wash....bet the left sleeve will have the compound still on it while the right will be clean. Setting compunds are not affected by humidity and can withstand temperature variations and hold the paper tape much better. Come next winter he should do one house this way and see the effects.

Myron Ferguson
04-05-2004, 08:30 PM
Thanks for the plug about my article. The drywall phase in construction needs a lot more respect