Hello all,
I have been asked about a job to install cornice and wainscoting in a room that has concrete walls. I was wondering what the best way would be to attach the molding. The wainscoting is going to be series of frames, not true paneling. Therefor, I won’t be adding any paneling to the wall to make it easier to attach the molding. I should be ok with the cornice because I can use a ramset to attach a nailer to the walls which won’t show. With the wainscoting and chair rail though, I am stuck. Is the answer liquid nails? Or a concrete fastener that I don’t know about?
I’d love to hear a couple suggestions. Thanks for your help.
Justin
Replies
You could use heavy duty self stick Velcro,
but scrub and dry the areas first'
Just use business card sized patches
placed at corners of frames
Steinmetz
Edited 2/14/2008 8:41 am ET by Steinmetz
Edited 2/14/2008 8:42 am ET by Steinmetz
Sounds like the start of a major headache. Some details would help. Above ground or below? Any sense of the amount of moisture coming through the walls? What is the condition of the wall, rough, smooth, wavy, seams or ridges? New concrete or old?
My advice in most cases would be to cover the entire wall with sheet rock on a stud wall or strapping to get a good surface that is easy to attach the molding to, then do the trimming. It will take less time and come out better than trying to attach moldings directly to the concrete.
John White
Thanks,I hear you about the headache. Did I mention the 5'R curved wall with windows? Think brownstone. It's third floor, not perfect walls, but smooth. Do you ask about the moisture regarding glue adhesion?Heavy duty velcro? As in it could come off after I attach it? Or is it more of a permanent version?Adding a better surface to the whole room would be a last resort. I had considered 3/8 MDF or something comparable. Studs and sheet rock would be too thick in that it would pull me out to far from window and door casings. Thanks for your help,
Justin
Here is a drawing of what I am talking about.Justin
Justin,
You are taking me back to my carpenter days.
The first thing I though of, was to route a groove in the back of the molding, and then attach a strip of wood the same size as that groove to the wall. You could fairly easily screw that strip of wood to the wall, and then attach the molding to the strip of wood with just some glue or a few small brads.
Of course this depends of if there is enough "meat" to the molding to allow for the groove.
Rob Millard
http://www.americanfederalperiod.com
That's the most elegant solution given yet -- good idea!
I asked about moisture for both adhesion but also for mold and rot problems, might not be a problem on an upper floor. So this is a brownstone building but the inside walls are cast concrete? Are you sure you aren't looking at plaster over lath?John W.
Thanks,But no, this is concrete. Tapcon is a possibility but I can't imagine how many holes I would have to drill for the whole room. And those bits always go dull on me after 2-3 holes even with a hammer drill. Am I doing something wrong?Right now the suggestion of attaching nailers that fit into a dado in the molding sounds like a good idea. Still, pretty time consuming. Of course, it's all going to take some time because there isn't a magic concrete brad nailer. Right?Thanks again everybody. You are always very helpful.Justin
What about using Tapcons, countersunk and plugged?
Beat it to fit / Paint it to match
I've used hard as nails to even re-attach tiles to a pool and it worked great. I have also used it to attach panel moldings to a wall;prepainted moldings and did'nt have to worry about nailing etc.
Ed
Liquid nails construction adheasive. I did a remodel on a house and used it under the framing between the concrete and you can break the wood away and bring concrete. Be careful it sticks to skin real well too. (don't ask me how I know).
If it moves, tax it. If it keeps moving, regulate it.
And if it stops moving, subsidize it.
I would agree that a construction adhesive would be the best way to go. My suggestion would be to build the molded frames on the floor as one piece so that the miters remain tight, after all this is what people will look at first. Using an adhesive allows the frame to float to the best plane on the wall. Caulk the back edge where it meets the wall. Painters caulk will be your best friend.
Some good tape and spacer panel that can hold the weight until the adhesive bites would allow you to work your way around the room.The curve sound fun!!! This is assuming the wall is of a finished look lending itself to such ornamentation??? I have created many premitered assembled frames for everything from mirror frames to ceiling frames (coffered ceilings)Its amazing how small a mold miter and pin with a 23 gauge pinner. If finished molds are required without pins, you can use instant (Crazy) glue and a accelerator to tack the mold until the wood glue sets.You would be amazed in new construction (commercial architectural millwork) how much stuff is glued in place. 3M is very good aat what they do!!!Hope this helps??? Jonathan
Yea Liquid nails!That was my first thought, but I didn't know how to "clamp" the pieces in place. That is smart assembling the frames first and then using a spacer to help out. Then tape it to clamp in place? Blue tape good enough or should I step up to the light green super strong stuff? The walls are painted now but will be painted again after I leave. Should I worry about the old paint? Should I scrape away in the areas I will glue?Is there a reason why I shouldn't use liquid nails? The other methods sound great but are time consuming. I don't want to lose my shirt on this one. Thanks again,
Justin
You can clamp with go-bars.
My only concern with adhering the wood directly to the concrete is the moisture problem that John White alluded to. Do you know what's behind the concrete? If the concrete is in direct "moisture communication" with the outer masonry, I wouldn't attach the wood directly to it. Instead, I'd space the paneling out on thin vertically-mounted lath (it doesn't need to be more than 1/4" thick or so), and leave a small gap at top and bottom of the paneling, to ensure that there was a ventilated drainage plane between the paneling and the concrete.
-Steve
Go bars...Do you mean spreader clamps for the crown/cornice (third hand clamps with a pivoting base and head)? That's what I was thinking. That solves the problem of the crown but not the frames on the wall. Tape still sounds good enough for me. That's what I use in the shop from time to time when traditional clamps don't work. That's usually for little stuff though. Thanks,
Justin
Go-bars are just springy pieces of wood wedged between the workpiece and some immovable object. Here's an example, on a much smaller scale, of using go-bars during the making of a guitar:
View Image
-Steve
I would suggest using the fiber tape, its a clear cello type tape with fiber bands, it will not tear when placed over sharp corners, and it will stretch somewhat which creates tension (ie pressure) Running out about 6" of tape pressing it well to the wall, then pulling it taunt over the molded frame and another 6" on the wall. A second pair of hands is helpful but not needed.
I agree that a mechanical joint is usually best, but for something that bears no weight (except is own which is not much) and faces no real wear and tear (ie decoration) the over would be overkill (ie cost you money)The only word of caution is the quality and condition of the painted surface, in reality you are not gluing to a concrete wall, you are gluing to paint! which is adhered to the wall. You may wish to wire brush the paint to get to concrete. A hand drill with wire wheel only where frames would be located. Moisture is a valid thought raised, if the wall is wet when applied then you have issues if not the use exterior rated adhesive if conditions change it should still hold. Just my thoughts!
Yep, and you can hold in place unless very heavy and it will hold. Big lesson, if you want to smooth it out, use a plastic spoon not your finger!!! It sticks to skin as well as concrete. First time I used it and smoothed a bead out so it could be painted. I thought it would come off like latex caulk, but mand it took for ever to wear off and some skin came with it! ouch. Great stuff though.Government's view of the economy could be summed up in a few short phrases: If it moves, tax it. If it keeps moving, regulate it. And if it stops moving, subsidize it.
The poster who suggested first attaching a nailer to the wall with Tapcons and then plowing out a groove in the back of the molding was, I think, on the right track. Though Liquid Nails has a good track record, I'd be much more comfortable with a mechanical connection rather than a glued one. Glues can fail, and you don't know how the concrete will react to the glue's composition. Would it produce a creeping stain that would bleed through paint? Would it erode?
It won't take long to attach the nailer to the wall, and that'll give you the opportunity to get the layout perfect. If you've got a good dado blade, running the molding over it a few times to create the groove won't take long either, and then you can just shoot it to the nailer, with no measuring or fiddling around required.
Zolton
* Some people say I have a problem because I drink hydraulic brake fluid. But I can stop any time I want.
Dear JB,
A lot of good suggestions have been made, but I would like to caution you about using a ramset on a wall with people on the other side. (You mentioned that is was above grade.) It is a long shot, but a nail could go clean through the wall and potentially kill someone on the other side. As I recall, a girl was killed in MacDonald's, mabe twenty years ago like that. Drilling would be a better option and with a modern rotary hammer, it should go fairly quickly.
Best,
john
I did this same thing before, in an old warehouse that was converted to loft living space. I build the frames first, then installed them. I drilled 3/8" holes about 2" deep and drove cedar pegs with glue into them. Then I used adhesive to attach the frames and, knowing where my pegs were embeded into the wall (marked with pencil), I fastened with hardtrim nails. Each nail was positioned (thus each peg hole was drilled) about 6" away from the corner. So basically, each frame had 8 nails - 2 for each side. Does that make sense? I hope so. I can draw a picture if you want.
Oh, and I whittled the pegs from cedar builders shims.
About the masonry bits going dull... Are you buying cheap bits? If so, you're wasting more money than you save. Also, you should always use them with a hammer drill. I mostly use my SDS Plus drilling masonry, as rotary hammer drill bits seem to be of a better quality.
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