I recently did a job installing crown in an entire house. To have a good nailing surface, I constructed corner boxes lapping the ceiling and the wall and screwed these to the house framing. I then installed the crown and cove moldings and coped all the corners. Any gaps between the molding and wall surfaces were calked. The job came out looking just great and many compliments have been received. Now that cold weather has set in, gaps are appearing between the ceiling and the finish cove molding and it looks terrible. What did I do wrong and how do I fix this? Please help, anyone! Bedub
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truss uplift!!??
Not much the finish carp can do except caulk!
Hope It is painted crown.
T
Do not try this at home!
I am a trained professional!
Thanks for your thoughts about my crown molding problem. Please explain - what is truss uplift? Thanks, Bedub
Joe at http://www.joesphfusco.com has great info on crown molding on his site.
At Darkworks Customer satisfaction Job One..Yea yea were all over it , I got my best guys on it.........
in a new house during the the first heating season the wood in the trusses which is usually dried only to 19% MC dries further, the bottom chords bieng closest to the warm interior of the house dry the most and consequentially shrink the most.
This differential in shhrinkage causes the truss to deform and lift up in the middle much like a crowned floor joist.
the truss takes the cieling with it, unless precautons have been taken.
the toe nails holding the trusses to the top plates usually give way and you get cracks in th drywall joint at the wall/cieling intesection.
since it is usually easier to find nailing into the double top plates, the crown will stay with the wall as the cieling lifts leaving a gaposis.
I Hope this is some help.
How'd I do Boss Hogg?
Mr TDo not try this at home!
I am a trained professional!
Thanks Mr. T for the really great explanation. It does make sense, however, I don't think this is the problem. The house is 35 years old so the trusses ought to be stabilized by now, right? If you would, please take a look at my reply to Ragner and let me know if any other thoughts come to mind. Thanks again!
I'm with Joe Fusco. We do a lot of crown moulding in NYC apts which are built of steel and concrete - prewar - and during the first year, after renovation, cracks and spaces develope between crown mouldings and ceilings, regardless of moulding size. And I assure you, the walls and ceilings haven't moved and the mouldings were installed tighter than tight.
We inform the HOs of this and tell them to call us back after a year and we will fill the cracks and touch up. If you do this be sure to mention what you will charge. Cracking will VARY depending on how dry/ hot they keep their rooms. I lost the cost of one guy for three days (client liked to walk around in t-shirt and shorts all winter) because I did not mention the cost up front - the year before.
This is just the nature of the beasts (moulding and clients). Good luck.
Mr. T did a pretty good job of explaining truss uplift. There's a whole thread on it here if you want to check it out more.
But - since you said: "The gapping is uniform throughout the house in every room." I'm almost certain it's NOT truss uplift. With truss uplift, you should have a fairly large gap in the middle of the house, tapering off to zero at the exterior walls. Doesn't sound like that's the case.A friend of mine did the most amazing thing. He caught a bullet in his teeth.He's dead, of course, but it was amazing.
One thing I forgot to mention -
"The house is 35 years old so the trusses ought to be stabilized by now, right?"
Not really. The age of the house has little to do with it. The top chord can still absorb moisture regardless of how old the structure is.Our relationship has been a great investment. But how do you feel about diversification?
Allow me to weigh in on truss uplift. It's a phenomenon. Usually limited to one or two trusses (note the key word trusses). It could also happen to hand framed roof/ceilings but for the most part unless they had webs, the chances are almost nil.
Typically, the problem occurs the first and, to a lesser degree, the second heating season the structure is new. It's a poor idea to fasten the bottom chords of trusses to the plates for a number of reasons: Trusses have camber designed into them to deflect when loaded - no nailing necessary. The other (and far worse) effect of nailing lower chords to the plates is - you guessed it - possibility of the bottom plate of the wall getting pulled up when the truss lifts! It happens, trust me.
The experts (no, I'm not one of them) claim the extent or severity is anyones guess. They further claim it is limited to one or two trusses. Hah! Built a house once and I'd guess at least 1/2 of the trusses lifted! Kinda hard to explain phenomenon to a homeowner with a 1/2 - 3/4" gap at the top of his walls. Line up the lawyers. We could get all the representation we wanted from our insurance co. They said we did everything right. Doesn't cure the problem and ruins your good name.
Sincerely hope it's not what you're going through.
"Usually limited to one or two trusses"
"The experts........They further claim it is limited to one or two trusses. Hah!"
So which is it? I'm confused by your post, as it seems you're contradicting yourself.
I have never heard of a case of truss uplift that is confined to "one or two trusses".
I have heard of truss uplift only happening the first year, then never occurring again. But I couldn't tell you what percentage of cases that happens in. I'd rather let Stevie Wonder wrap my parachute.
super stretchy caulk
Bedub1,
I haven't experienced specifically what you're talking about, so I can only take a couple of guesses. How big are the gaps? Also, what exactly do you mean by "corner boxes"? Is it just a back-beveled piece of trim that spans between the ceiling and the wall at the same spring angle as the crown?
It's hard for me to believe that the ceiling is somehow moving upwards. If this is actually the case, I think there would be cracks in the corner of the sheetrock, too (where the ceiling meets the wall). Is there any place where you could look and see if this is the case? Perhaps in a bathroom or closet that didn't get ceiling crown?
Otherwise, I would assume that the crown itself is contracting due to the cold temperatures, and the very low humidity that usually accompanies it. I've seen pieces of stop mold shrink up enough to get loose, whereas they are sprung tight during the rest of the year.
I would try getting some nails through the crown and into the ceiling framing wherever possible, if you haven't done this already (Edit: this depends on my understanding of your "corner box" construction, too). Also, as others have said, use some more caulk.
Let us know what you find out.
Ragnar
Edited 12/31/2002 2:20:11 PM ET by ragnar
Thanks, Ragnar, for your comments. The corner boxes I built are made of 1X4's, screwed together and then screwed tight to the framing with 4" screws. The crown is mounted between the two planes of the corner box and the ends of the box are finished with cove. There are no gaps in the crown itself. The gaps are occuring where the cove meets the ceiling. Some of the moldings were installed over the winter months and some were installed over the summer months. Time of installation does not seem to be a factor as both varieties are experiencing the same problem. This problem has only just occured with the onset of the colder months. The house is a ranch, 35 years old, and when the molding was installed, there were no cracks or gaps at the intersection of the wall and ceiling wallboard anywhere in the house. The gaps are as wide as 1/4". Does this this description help?
Bedub,
Thanks for the clarification - it helps a lot to visual the problem. With three elements (upper cove, crown, lower cove), it sounds like a very nice design. And with the sub-elements (i.e. corner boxes) screwed into the framing, it really sounds like you did a first rate job of making this thing bullet proof. It must be pretty damn frustrating to be having a problem with it now! ;)
If the gap is forming between the upper cove and the ceiling I can think of only two possibilities. Either the cove is moving, or the ceiling is moving! What is the size of the upper cove, and what is it made of? Finally, look at the relative position of the upper cove to the crown. That is, is the upper cove staying nice and parallel to the crown? This observation should tell us whether the cove has moved.
Ragnar
Edited 12/31/2002 5:33:11 PM ET by ragnar
Thanks again Ragnar for your continuing interest in this problem. The upper cove is not doing the moving. It is clearly the ceiling that is moving. I can tell you that there is an insulated crawl space above the ceiling (this is a ranch home) with R-13 batts over the wallboard between each joist. There is a ridge vent across most of the span of the house and soffit vents front and back. In the winter, it is unbearably cold in this crawl space and unbearably hot in the summer. Could my problem be expansion/contraction of the ceiling wallboard and possibly lack of humidity in the living space of the house. It is hot water baseboard heat and there is no humidifier? I'd be interested in your thoughts. Thanks again, Bedub
Forgive me if this has already been stated, but is this gapping uniform throughout the entire house or is it random and intermittant?
Knowledge is power, but only if applied in a timely fashion.
The gapping is uniform throughout the house in every room.
Is the attached what you did?
Almost! The crown fits between the horizontal surface and the vertical surface of the "nailer box". Then, cove finishes each edge of the nailer box along the ceiling and along the wall.
Ok! So where is the gap?
Nigel,
From what I understand, he's got small cove molds installed to hide the 1x4 subframe, one cove above, one cove below. From this, I'm assuming the cove is only about 3/4" x 3/4", or maybe 3/4" x 7/8".
Anyway, the gap is occuring between the face of the ceiling and the upper edge of the cove.
Ragnar
Bedub,
If the ceiling is moving, it's hard for me to imagine that it is moving without pulling that 1x4 along with it, since you've said it's anchored with 4" screws! And isn't the upper cove nailed to the 1x4?
Just to try to figure this thing out, I would remove one stick of the upper cove at some location where the problem is bad. Then, you'll have a chance to see if the 1x4 is separating from the ceiling.
The only remedy I can offer at this point is to nail the upper cove to the ceiling instead of to the edge of the 1x4. In this way, if the ceiling moves, the cove will go with it, and a gap won't appear. This remedy assumes that the gap along the ceiling will be more noticeable than variation between the edge of the upper cove and the crown.
This is a real hard problem to figure out! If you do, in fact, pull one of the upper coves to investigate, remember to post your findings here -- I'm very interested to see what you discover.
Ragnar
You stated in your first post that all gaps were caulked and so I'll presume this means that there were gaps there to begin with. How large were these gaps and what brand and type of caulk did you use? What is the current state of that caulk now…….is it stuck to the ceiling….to the molding……or is it tearing itself apart?
I'm thinking that a contributing factor may be that the back side of the moldings do not have the same humidity exchange rate as the front/show side and this may be causing that cove molding to cup, if you will, producing it's fair share of the gapping you're experiencing. It's my understanding that these cove moldings are only fastened along their bottom edge. However now that a gap has developed, the molding should start flattening out again (or at least has the opportunity to) to some degree as its backside has a bit more access to relative humidity.
IME, this sort of gapping problems with crown moldings is somewhat commonplace, I'm afraid to say. As others have suggested here, I think one of the better ways to deal with it is to figure out a way to disguise its fickle state in one's design rather than to struggle in an attempt to prevent it.
Knowledge is power, but only if applied in a timely fashion.
Bedub1,
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Thanks for your comments, Joe. Please see my reply to Ragnar and let me know if any other thoughts come to mind. Thanks again.
Tell your clients (or yourself) to crank up the humidifier! Ignore it a smuch as they (you) can and take another look at it in July.
Eric
What kind of heat source is there? Forced hot air?
Was the crown moulding allowed to sit on site and acclimate itself to the existing environment for at least 1-2 weeks?
Was the istallation done in a non conditioned environment?
Thanks for your interest in this problem. The heat source is hot water baseboard heat. The materials for construction were on site for at least 2-3 weeks and for as long as 8-10 weeks. Most of the installation was done when the house was empty over the winter months and the thermastat was set at 60. Some was done extending into the spring and very early summer. There was no air conditioning and there is no humidifier. I hope this helps in your diagnosis. Thanks for the interest. Bedub
I can offer you what I have learned in my experience. First when winter arrives and the heat comes on in your home the humidity level in your home drops off the scale. The dry air causes the wood crown moldings to dry and shrink, you may have noticed this in your hardwood floors. In Summer when the heat is turned off in your home the wood should swell back to the size it was when you installed it. The smaller the crown the less it will obviously shrink. I use 4 inch screws to affix painted crowns. I sink the screws right into the top plate. I then use an epoxy fairing filler to fill holes, then sand to smooth finish. I also biscuit join all butt joints in the crown molding run. I never cut a beveled joint in my crown molding runs. I good biscuit joint and a little sanding will make the joint disappear. I avoid any caulking inside the interior of a house. After one heating season it will become loosened and crack and in some cases fall out. Another solution is to install a 2 piece crown. The piece that you install against the ceiling should have a slight radius or bull nose. This way any shrinking will be hidden by the shadow line you have created with the radius. I also will prepaint the "bull nose" piece before I install it because it would be very difficult to get a good paint line after this piece is installed. Also I know a lot of so called purists out there that would never advocate this, but......I have found that crowns that have a very complicated profile can be very difficult to cope. I have found that mitering the joints and then screwing the joint from behind is a very good method of joinery. The joint comes out perfect and if it is screwed from behind well, it will last a forever and I challenge any one to try to cope one of these crowns without calking and make it look better than mine. And I can do my joints in less time this way too. I still cope joints but only in the simpler profiles.
Edited 1/1/2003 9:30:14 PM ET by ww_aficionado
Edited 1/1/2003 9:32:22 PM ET by ww_aficionado
To everyone who weighed in on my problems with crown moulding gapping along the ceiling line (12/31/02), the two solutions that seemed to make sense were a lack of humidity and ricky's suggestion to apply super streachy caulk. I noticed that of all the crown installed, the only place where it didn't gap was in the kitchen. It occured to me that because the house has hot water heat with no humidifier, the only place where some humidity was being generated was in the kitchen while cooking or washing dishes. Hence, no gapping. Also, in the summer months when humidity is high, there also was no gaping. So that seems like the logical cause. I did find some new caulk that DAP is now manufacturing. It was easy to work with and it restored the mouldings to their original pristine condition. Since application two months ago, there have been no gaps. Seems like the case has been solved. Thanks for all the education and input form ya'all. BeDub