THOUSANDS OF SCREW POPS

One of my favorite magazine ads is of a drywall contractor standing in front of a couple who are his customers. He is gesturing toward a white painted wall that is completely bare. The caption reads: “MOST ART IS APPRECIATED WHEN IT IS SEEN -YOURS IS WHEN IT ISN’T”

I recently had a general contractor ask me about a drywall job they were involved in. The house is finished and people have lived there a few months. He does not remember anything unusual when the drywall was hung and taped, but there are now thousands of screw pops.  These pops are along the edges and in the field, and on both interior and exterior walls, although worse on exterior walls. Some on the ceilings, but mostly just edges.

It takes about 46 screws to attach a 12-foot piece of drywall to a wall, and 54 to put it on a ceiling. The amount of drywall that a crew can hang in a day varies because of the crew’s ability, the number of hangers in the crew and the type of job. Typically, we hang 4,000 to 5,000 square feet a day, which requires about 4,700 screws. That comes out to about 1,000 screws for 1,000 square feet of drywall. It is not uncommon to have a dozen or so screw pops in an average house but most of these are discovered and corrected by the tapers before the job is done. After a full year cycle of seasons a few more may show up but they are often left alone until the customer decides to paint. So thousands of screw pops is a serious problem. If it is the result of a very poor fastening job then it is difficult for me to believe that no one noticed the poor quality work as it was being done. In many parts of the country the hanging is inspected before taping can begin. The GC and the owner of the drywall company should also have caught the problem.

A screw is either set right or it is set wrong. Out too far is obvious and it can’t be concealed unless you build up the compound and create a bump. Just a slight difference in a  screw set makes a difference.  In photo to the left: The lower screw is set just a little too deep and is more likely to pop than the upper screw. In too far is not as obvious. Most of the time if an occasional screw is set too deep it will not be  a problem because it is still holding the drywall tight and other screws in the area are also holding the drywall tight to the framing, so it will not show up when sanding and may never show up as a pop. But it is a week attachment and is more likely to pop if there is structural movement or an impact on the wall or ceiling. The contractor with the screw pop issue stated that anywhere he  pushed it caused screw pops. This indicates that the drywall is not tight to the framing. Perhaps the screws were so poorly set that the drywall was never tight to the framing which would mean than it was somehow taped and sanded and no one noticed that the drywall was loose. This would be difficult to believe. So maybe the drywall was not tight to the framing because the insulation was pushing out on the drywall so the screw did set and was finished without showing up as being loose, however the contractor stated ,the pops are everywhere, even on un-insulated walls. Maybe too long of screws were used. The screw should penetrate the wood about 5/8 of an inch.  A 1 ¼” screw is most commonly used for attaching ½” drywall.  I know this is more than 5/8” but I have never seen a 1 1/8” screw.   You might think that a  2” screw would be better but it is actually worse because it is harder to put in straight. So a screw set crooked will tear the paper on one side and be either too deep on the other or not deep enough. Also if the framing were too shrink a longer screw is more likely to pop.   Using drywall adhesive along with screws is a good idea because it does help reduce fastener  pops when the screws are improperly set or if there is minor structural movement. It also develops excellent shear strength and reduces the potential for bowing or sagging.  I like to use adhesive but it doesn’t work over poly or Kraft paper insulation.  Personally,I have never had too many problems with screw pops if  I have done the fastening, but if some one else has done the fastening and  a lot of the screws are set a little too deep but the drywall has been glued then I am confident that I still will not get any fastener pops. So all in all I like to have my subs glue the drywall where ever they can.

When fastening drywall to walls I attach the drywall 16” on center.  Two fasteners in the field and one on each edge. Ceilings go 12 inches on center. Work across the panel by starting on one edge, then fasten across the center, and then the last edge. This allows the screw to pull the drywall tight as it is set.  Controlling temperature, humidity, and airflow before, during and after the drywall work is real important.  Believe it or not just bringing the drywall in ahead of time to acclimate (just like hardwood flooring) can help reduce problems that often appear within 24 hours of first turning on the heat.

I have never had thousands of screw pops.  I have had a few hundred a couple of times but most of the pops were along the top plate. I now recommend fastening about 7 inches down off the top plate to avoid this problem. I usually use drywall adhesive just because I try to offer my customers the best job possible. I didn’t start using adhesive because I was having problems.  I started using it since I am always striving to meet or exceed my customer’s expectations and to avoid problems instead of putting out fires.  Building a house or an addition is like putting together a chain, the links are all put together as the job progresses but the chain is only as strong as the weakest link.

In Conclusion:  It’s a pretty safe bet that some sort of shrinkage occurred to have so many screw pops. Since it’s uncommon to get that many pops, something unusual had to happen. I’m guessing that it’s a rare combination that caused the problem, kind of like an accumulative error thing. The overall system can deal with one or two bad conditions, & still work with minimal pops. If this home had 3 or 4 contributing factors, then it was doomed. I’m thinking maybe the lumber had higher than normal moisture, the drywall had a somewhat soft core, the drywall got damp when stocked, the screws were set in a less than perfect method, & the pva paint trapped the moisture, only to work it’s way out at a later than sooner point in time. Normally any two of these would be ok, but this is a rare case of an accumulation of problems.
How else could you explain severe popping not happening more often, since all of these factors are fairly normal?

© Myron R. Ferguson

 

27 thoughts on “THOUSANDS OF SCREW POPS

  1. we are having the same problems i think the light weight is to stiff and the screw will not pull drywall tight to stud done with light weight

  2. I am having the same problem. Lots and lots of screw pops. What would be our recourse with the gc. We really don’t want a thousand patches

    • Hi Dale, If you already have the screw pops they will have to be fixed. The screw may be able to be just turned in slightly with a screwdriver. Or maybe another screw installed next to the old one. In some case the screw may be just removed. After re-coating with compound and sanding the areas will all have to be primed and painted. If a paint with a sheen was used then the entire surface may have to be painted again to hide the repair. As mentioned in the blog there are a number of reasons for the problem and it is usually the result of poor jobsite conditions. Once the building has settled and dried out the screws problem should not return.
      Myron

  3. My problem is that the screw heads are protruding outward, I think the new light weight drywall had to much moisture and when the house heat was turned on the board shrunk. And I glue the heck out of it ?? I would like some tech info on moisture #’s Please help!!! I have been a drywall contractor for 40 years & haven’t seen this until light board came out.

    • Hi Marc, I would say it does have something to do with moisture. Most likely too much moisture in the framing. Using drywall screws that are too long can also cause some nail protruding out. Whenever I do a moisture test on drywall it is around 14% so I try and have the framing less than that before I hang. Keeping the humidity as low as possible while taping will also help eliminate problems.
      I haven’t experienced any problems with the lighter weight drywall. It does seem to have a harder core which seems to have less give when setting a screw. So when the screw is set it is more prone to tearing the paper than with the old drywall. But not significantly worse. You just have to be more careful when fastening and occasionally but in an extra screw next to one that was set too deep.
      Myron

  4. Having pop issues on a job installed several weeks ago, swear I did everything right, glued to strapping 16” centers, drywall tight and glued, screws still protruding.. Have 25 years experience as contractor carpenter, ,only started seeing problems recently, this one is much bigger than anything in the past. Sent back g.p. drywall, was defective, had voids, misformed taper. Ended up with certainteed, seemed o.k. Hundreds of pops. Customer insisting that it is ok and no one will notice , but worse everytime I look at. Don’t really know what is going on. The only thing I can possibly think is strapping was damp, didn’t seem wet, like I said installed a lot [relatively] of rock. didn’t put a moisture meter on it,so m.c. unknown, but would guess was o.k.

    • Just went to job, this was old house, all settled down, as far as framing etc. . Insulated walls with foam board, 3” in a 4” cavity, no problem on walls. Ceiling strapped 16” center, bedroom above, relatively leaky, air wise, dry basement. nailed strapping , ring shank 8d, 3 per joist, angled to oppose each other. Found pc of strapping in garage, m.c. 12, also found pc drywall, certainteed eazy-lite, 1/2”. Glued drywall to strapping with low cost liquid nails. Screwed 12” o.c., 1.25 ” screws. Screws near tapers/ butts are not showing . At wall ceiling junction, screw 12” from wall not showing. Set screws with cordless drill and ‘dimpler bit’ from lumber yard, same as always. Drove a screw next to several pops, the drywall appears to be tight to the strapping, as in glue set well. Toke a hand screw driver to pops, it seems like every screw I checked could be tightend about a half turn. Also, remembering that when we started project had to remove a sheet that had been glued and set overnight, glue was well adhered, continuous. Don’t know why screws are loose.Something to do with rock, possible that glue shrank?

    • Could be wet strapping. When you inspect each screw is it loose? In other words can you tighten it just a little to bring it tight to the drywall? Is the screw now a little off center of the dimple likes something has sagged?
      Myron

  5. So with a little research ,I come up with this, the boards were certainteed easi-lite lightweight gypsum board. There is also a product called certainteed easi-lite gypsum ceiling board. Lumberyards around here don’t carry the ceiling board. The brochures online show the litewieght gypsum boards as being good for walls. the published specifications in the same brochure also show that these boads can be installed 24”o/c on ceilings with latex texture. Then there are ceiling boards that are ‘sag resistant’ Have to wonder if they are going to phase out the wall panels. Will be calling certainteed in the a.m. monday

  6. spoke with certainteed this a.m., rep told me I should have used 1” screws, no possibility that it was anything other than lumber shrinkage. I am near concluding that litewieght is difficult to install, and if things are not exactly exactly perfect there could be issues. Drywall does not get applied to dead perfect structures.

    • So I carefully removed compound over each screw head. Each screw was loose by less than a quarter turn. Some tapered seams appear to have swelled, and are now visible. Idont remember if I mentioned that this was a ceiling that we ‘on and off’ with compound everywhere. Going over screwheads one coat /24 hrs.

  7. Hi, I’m a drywall contractor in michigan and I just wanted to throw out my 2 cents. wood breathes, and glue shrinks. a giant glob of glue behind the screw will dry up, pulling the drywall closer to the stud, thus pushing screws outward. when i do ceilings, i use a tiny bead of glue and lots of screws making sure the drywall is tight to the wood. And heres my fool proof way of doing walls – use big globs of glue in the field to grab the drywall and give it a solid feel – but no screws in the field. screw off the perimeter of the sheet where all screws get taped over or trimmed. you don’t need them, your not fighting gravity like ceilings. Or just pull the screws out after the glue is set for a couple days.

  8. I have been in the business for 40 years I believe part of the problem is the lite weight board, this board has too many air bubbles that make it lite weight, so drywall screw are never tight we never had this many screw pops when we were
    using regular drywall.

    the other problem is the drywall glue OSI F-38 this is latex base, moisture and cold make it weak and cause more screw pops and bad seams.

    back when we were using miracle DSA-20 drywall glue we did have all these screw pops and bad seams, but this is a solvent glue and not allowed in Illinois, I believe these are the issues we are have today.

    • Hi Rudy, Not sure about the lightweight drywall except that I think having the screw properly set (not too deep) is even more important and that because the core of the light weight drywall is coarser the paper does tear easier when setting the screw. So you may be on to something!
      Below is some info I found on latex drywall adhesive that you will find interesting.

      USG FASTENER RELATED DRYWALL INSTALLATION ISSUES AND RECOMMENDATIONS
      In the last two to three years, USG has received a significant number of fastener-related drywall
      installation complaints in the Mid-Atlantic region (Virginia, Maryland, Pennsylvania, New Jersey
      and New York). Numerous drywall contractors within this region have reported raised bumps over
      drywall screws occurring anywhere from a few days to several months after hanging and finishing
      the drywall as shown in figure 1. The reports were specific to wood-framed residential construction
      finished with 1/2″ USG Sheetrock® Brand UltraLight Panels with limited occurrences reported on
      5/8″ USG Sheetrock® Brand Firecode® Core Gypsum Panels.
      Figure 1: Drywall screw bumps
      In order to assess the situation, USG representatives visited with drywall contractors on various job
      sites in the Baltimore and Philadelphia markets. The drywall contractors described these fastener
      problems as a raised circular protrusion or bump directly above the fastener similar to a “Nail Pop.”
      These bumps or “Screw Buttons” would occur randomly throughout a given home and were not
      tied to any specific wall (exterior, interior, ceiling, stairwell, etc.). They would appear anywhere
      from a few days to several months after hanging and finishing the drywall. After an extensive
      evaluation of the drywall installation process, the following commonalities were identified:
      1. All residential wood-frame construction
      2. Primary drywall used was 1/2″ USG Sheetrock® Brand UltraLight Panels
      3. All drywall contractors used standard drywall screws
      4. All drywall contractors used low-VOC water-based drywall adhesive
      a. This adhesive was primarily used in the field of the panel and not at the taper or butt joints
      5. The drywall screw buttons only occurred in the field of the panels

      Myron

  9. Just saw the usg fastener related drywall installation issues and recommendations, they lay the problem on uncured low voc glue. Say there have been many, many complaints. They saythey can reproduce the problem, and make it go away. Believable in my situation John Mccloskey

  10. I dry walled my basement after the wood framing was done 6 months previous. Lightweight 1/2″ board, liquid nail glue, 1 5/8 course screws. I glued all studs and screwed 12″ centers on every stud, screw set below surface 1/16th inch field and perimeter and still pops everywhere. SICK about it. This occurred 6 months after the job completed.

    • Dave, Explain to me what the pops look like. Is it a slightly raised bump over the screw? Is the drywall now loose or is it still glued tight? Is the screw now loose? By this I mean does it now need to be slightly turned in with screwdriver?.
      Was the adhesive you used a low VOC water based product?

      • The pops are easily visible because I like higher sheen paint like satin. Every fastener can be found. Probably 1/16th or less bump. I see the paint stretching around the perimeter of the screw hole. Drywall is tight (very tight) to the framing everywhere, none of the board is loose. The glue was applied on every wood stud vertical and horizontal heavily. I don’t remember the brand but it listed drywall panels as one of the proper uses. I did take a hand steel roller and flatten some of bumps, so the screw is still beneath the surface. I probably pulverized the filler mud originally applied. Has this drywall product been tested for overall shrinkage in thickness after sealer paint is applied? I think this is more likely the case than every course screw I installed backing out for another reason. I can see a nail over time getting pushed out, not a screw and a course one at that. I’m going to adapt a new method of hanging the light weight drywall. Lots of glue no permanent screws except under trim, base, case, or crown areas. I will remove all exposed screws after a day or two, then finish. Thanks for your response.

        • You may have applied the adhesive too thick and as it dried it shrunk. This would pull the drywall tighter and cause the compound to bump out. This has been a problem with some low VOC water based adhesives. Adhesive companies have become aware of this so I assume it is being corrected because the problem occurred about 5 years ago.

  11. Not only do we have 20+ screw pops, and more keep on showing as the sun hits the wall at different times during the day I begin to notice on the wall in my living area on the cathedral ceiling I can actually see where each stud is located. How could something like this be resolved? I can see where they screwed or nailed into the studs as they are popping out and more are coming out. I counted it 2 months ago, so I know the count is much higher. Thank you.

    • Not really sure what you can do besides re-fasten. Hopefully you can just turn in the popped screws. That way you can just recoat with compound and not have to use any tape. If you use tape you will have a hard time hiding because you are creating a bump

  12. A few notable factors:
    I started drywalling in 1971, taping in 1976. My first screw gun was an old Milwaukee gun running a low RPM, never problems with pops. Todays’ guns run much faster RPM, and the clutch will disengage before the drywall is pulled tight against the studs. It is crucial to set the correct depth, if too deep,the screw will cut the paper, and eventually cause a pop. Excess moisture is another problem during
    application, taping, and priming. Water mixed in the primer will be absorbed by the drywall and the taping compound, creating tons of problems including nail pops afterwards

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