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Rick Huelsbeck
01-03-2010, 10:53 AM
We are putting drywall up in my girlfriends basement, we made the mistake of not lining up the indentations around the edges as we had to cut the bottom sheets (she wanted to put it in sideways as opposed to vertical and well I get tired of trying to tell her she will have problems :mad:) anyway my question is 1) can it be mudded without tape? It's starting to crack in places and this could be because the first coat shrank or will we keep having this issue? 2) on the side that is high( no indent as that is where it was cut) can we sand in an indent to put tape?

Michael Wetzel
01-03-2010, 10:58 AM
You have to tape it or the mud will crack. As far as the uneven areas, tape it and fill the extra space with mud. You will need to feather it in over a larger area to hide the "bump".

Dave Johnson29
01-03-2010, 11:14 AM
can it be mudded without tape?

Not without cracking sooner rather than later. The expansion rates between the wall frame and the drywall will quickly see to that.

Use paper tape and not the self adhesive fiberglass stuff. Use a brush to put a thin coat of mud where the tape is to go. Use a wide blade (10") to smooth mud from both sides. Use low pressure so the edge of the tape creates a slight slope from each side. Sand to take of the major bumps then mud again. This time sand carefully for a final time. If you hit the edge of the tape when sanding it will go fluffy so mud over it and sand again.

It is a lot more work, but since the drywall is in, you have no other option as I see it.

Mike Henderson
01-03-2010, 11:40 AM
I haven't done a lot of drywall, but I always put it in horizontally and staggered the seams (so I didn't wind up with a single vertical seam). No one commented on the vertical verses horizontal laying of the drywall, so I'll ask for comments from the pros.

Mike

David Epperson
01-03-2010, 11:46 AM
Every time I've ever installed drywall it has been horizontally - with the possible exception of very short walls (less than 4' long). I'm not a professional hanger - but every installation I've seen was done that way as well. But then again I've installed some 4'x12' sheets that would have been impossible to install vertically too.
Tape ALL the joints, or you will regret it later. The good news is that nowadays the "gauze" style tape goes on easier and takes mud much better than the older paper tape.

Mike Henderson
01-03-2010, 12:09 PM
Rick also commented that he put the partial sheet on the bottom. I've always laid the drywall with the full sheets on the bottom. Any partial sheets were always done at the top. That way, I can sit the second sheet on top of the first, and the partial sheet is lighter when I have to raise it all the way to the top.

But I've only done it for my own remodeling - I'm definitely not a pro and really dislike doing drywall.

Mike

David Epperson
01-03-2010, 12:14 PM
Likewise on not being fond of the job. But all of it we've ever hung was top sheet butted to the ceiling, bottom sheet butted to the upper sheet. That way any cracks are covered by the floor trim.

David G Baker
01-03-2010, 3:43 PM
I like the sheets horizontal and butted to the ceiling like David E wrote. I also only use the mesh or gauze type tape. I try to use 10 or 12 foot sheets as well where they will fit. I cover door and window openings in new construction with sheets and cut the opening out with a Roto Zip, this makes for a much neater look and less mudding. One other thing, try not to have sheet seams to close to electrical outlets, it is a pain to finish them.
I am getting to the point where I can no longer handle a long sheet of 5/8" wall board with out help and it won't be long before I have trouble with 4x8 sheets of 1/2". Getting old can sure be a pain in more ways than one. :D

keith ouellette
01-03-2010, 4:11 PM
Like everyone said it has to be taped. It is so important I would do what ever it took to re do any area you did without tape. It will crack and re crack every time you fix it.

I for one like the self adhesive mesh tape. you will find it better if you are new to finishing. dont over lap the end on any joint that does not have a beveled depression because it could show through after sanding or make a slight hump.

make sure you do the joint compound in 3 coats (many people say 2 coats but I like to do it in three). It may seem like a pain but it will avoid a lot of problems.

Put your mesh over the seam, sticky side against the wall.

use a 4 (or6") knife to embed the mesh and fill the void with fast setting compound

don't get any thing that sets up faster than 30 min and start out with small batches till you get used to it. two hawks (or troughs) and one person mixing and cleaning the hawks and the second applying the compound makes it go fast.

switch to a 6" or 8" knife with the same fast setting compound

then finish with a light weight easy to sand pre mix compound and a 12" knife.

this will make certain the bevel is completely filled across its width and will eliminate a lot of sanding.

David Epperson
01-03-2010, 4:25 PM
this will make certain the bevel is completely filled across its width and will eliminate a lot of sanding.
I will NEVER sand drywall mud again...PERIOD. Even with a mask I'm too sensitive to the dust anymore. I'll wet sponge finish it, but sanding it felt like it just about killed me. I'm still on asthma meds from the last time I was around it and that was close to a month ago. Felt a whole lot like pneumonia.
I didn't get to the coughing up blood stage...but I only lightly sanded the stuff for 15-30 minutes on a single day.

Dave Schreib
01-03-2010, 7:49 PM
The joints you are referring to are 'butt joints' and they are harder to tape then the joints that have matching indentations. In my experience (3 diy basements) the better tool to use for butt joints is a trowel rather than a knife. Trowels have a slight arc in the length of the blade that allows you to leave more mud in the center of the stroke than at the edges. That is important when you need to build up the mud over that joint and then feather it out over the course of maybe 18" or so. These are hard to do well, but if you take your time and keep the frustration in check you should be able to do a decent job. For me, sanding these joints worked better than sponging them.

Ditto what has been said about the need for tape.

Here's a link that helped me when I started tackling this stuff:

http://www.drywallinfo.com/index.html

Jack Wilson
01-03-2010, 9:15 PM
Hello everyone, I am new to your forum but not new to drywall. So... yes you have to tape it, period, as stated earlier you'll want to feather it out. Additionally I strongly recommend putting on THIN coats. I start out with a 6" knife, put the mud on and then run my knife across and essentially thin out what I just laid in. Then I run my PAPER tape across all that trying to keep it centered on the joint, then bury that in by starting in the middle of the seam and working as much mud as I can out from underneath the tape. Then work the other direction. LET IT DRY. Then I go to an 8" knife and lay more mud on, skim most of it off, let it dry then finally I use a 14" knife to finish it off. Lastly I sand, the nicer you feather out your work, the easier your sanding will be. Also note that after the first coat has dried, if you notice any bubbles, you'll need to get the corner of your knife under there and lift it up, put some more mud under it and work the mud out again. You can't bury bubbles, they work through all the layers.

I see a note about trowels rather than knives, I arc all my knives 8" and wider by putting them on a flat surface an pressing the blades down to the surface, letting the handle keep the center up and so giving them a slight bow, a little at a time and easy does it.


I wish you the best,
Jack

Jim O'Dell
01-03-2010, 10:50 PM
I haven't done a lot of drywall either. But for walls, I'd install it vertically so that you don't have the butt joints except where it meets the ceiling. With ceilings,or walls over 12' tall, there is no way around butt joints. You just have to feather it out a long ways so the change in thickness disappears. Note, it doesn't go away, or go flat, it just hides it.
And yes, the dust is nasty. Have at least a paper filter on when doing it. I also bought a hand sander that uses a screen to sand, and hooks up to a shop vac. I add a hose to the exhaust and put it through a window to get rid of any filter blow by, and it does blow by!!! Jim.

Dennis McGarry
01-03-2010, 11:15 PM
if you put the non feathered joints together you will have a very hard time feather that out, think like min 12in trowel at the min. then it will always be a little higher.

The method to use when putting the butt ends together is to take the razor knife and slice down the seam at a 45 degree angle on each one, reating a indentation. But you cant do that now

One easy diy method in a basement would be to use white paintable silocone caulk in the seems, fill them in, smooth out and paint. will be very faint if at all and will allow the board to move a little and not crack. well it will but not very much you would notice it.

For a main room could plane it down a tad as well and then tape and mud as normal.

phil harold
01-04-2010, 3:50 PM
Dry wall is all an illusion of square and flatness
on non-tapered joints you feather out at least 12" on each side of the butt joint

depending how light shines on the wall you may have to feather 24" inches for a smooth finish and possible skim coat

but if you spray texture it can hide alot

there is 6 levels of dry wall finishing
###############################################

Level 0
No taping, finishing, or accessories required. This level of finish may be useful in temporary construction or whenever the final decoration has not been determined.

Level 1
All joints and interior angles shall have tape set in joint compound. Surface shall be free of excess joint compound. Tool marks and ridges are acceptable. Frequently specified in plenum areas above ceilings, in attics, in areas where the assembly would generally be concealed or in building service corridors, and other areas not normally open to public view. Accessories optional at specifier discretion in corridors and other areas with pedestrian traffic.

Some degree of sound and smoke control is provided; in some geographic areas this level is referred to as “firetaping.” Where a fire-resistance rating is required for the gypsum board assembly, details of construction shall be in accordance with reports of fire tests of assemblies that have met the fire-rating requirement. Tape and fastener heads need not be covered with joint compound.

Level 2
All joints and interior angles shall have tape embedded in joint compound and wiped with a joint knife leaving a thin coating of joint compound over all joints and
interior angles. Fastener heads and accessories shall be covered with a coat of joint compound. Surface shall be free of excess joint compound. Tool marks
and ridges are acceptable. Joint compound applied over the body of the tape at the time of tape embedment shall be considered a separate coat of joint compound and shall satisfy the conditions of this level.

Specified where water-resistant gypsum backing board (ASTM C 630) is used as a substrate for tile; may be specified in garages, warehouse storage, or other similar areas where surface appearance is not of primary concern.

Level 3
All joints and interior angles shall have tape embedded in joint compound and one additional coat of joint compound applied over all joints and interior angles. Fastener heads and accessories shall be covered with two separate coats of joint compound. All joint compound shall be smooth and free of tool marks and ridges. Note: It is recommended that the prepared surface be coated with a drywall primer prior to the application of final finishes.

Typically specified in appearance areas which are to receive heavy- or medium-texture (spray or hand applied) finishes before final painting, or where heavy-
grade wallcoverings are to be applied as the final decoration. This level of finish is not recommended where smooth painted surfaces or light to medium wallcoverings are specified.

Level 4
All joints and interior angles shall have tape embedded in joint compound and two separate coats of joint compound applied over all flat joints and one separate coat
of joint compound applied over interior angles. Fastener heads and accessories shall be covered with three separate coats of joint compound. All joint compound shall be smooth and free of tool marks and ridges. Note: It is recommended that the prepared surface be coated with a drywall primer prior to the application of final finishes.

This level should be specified where flat paints, light textures, or wallcoverings are to be applied.

In critical lighting areas, flat paints applied over light textures tend to reduce joint photographing. Gloss, semi-gloss, and enamel paints are not recommended over this level of finish.

The weight, texture, and sheen level of wallcoverings applied over this level of finish should be carefully evaluated. Joints and fasteners must be adequately concealed if the wallcovering material is lightweight, contains limited pattern, has a gloss finish, or any combination of these finishes is present. Unbacked vinyl wallcoverings are not recommended over this level of finish.

Level 5
All joints and interior angles shall have tape embedded in joint compound and two separate coats of joint compound applied over all flat joints and one separate coat
of joint compound applied over interior angles. Fastener heads and accessories shall be covered with three separate coats of joint compound. A thin skim coat (Ref: Terminology, Section II, page 2) of joint compound or a material manufactured especially for this purpose, shall be applied to the entire surface. The surface shall be smooth and free of tool marks and ridges. Note: It is recommended that the prepared surface be coated with a drywall primer prior to the application of finish paint.

This level of finish is highly recommended where gloss, semi-gloss, enamel, or nontextured flat paints are specified or where severe lighting conditions occur.

This highest quality finish is the most effective method to provide a uniform surface and minimize the possibility of joint photographing and of fasteners showing through the final decoration. http://www.buyezrip.com/Drywall-levels.htm
###############################################

JohnT Fitzgerald
01-04-2010, 3:56 PM
you definitely should tape, or you'll fight cracks from now until a quarter-past forever. :)

One tip I picked up from a drywall friend is this - score the paper on the "non-indented" piece, about 4" way from the seam. peel the paper off, which will give a very subtle indentation. then use paper tape.

Eric DeSilva
01-04-2010, 4:19 PM
I seem to be the exception, but I'd hang it vertically. I did the drywall horizontally last time, just because I kept seeing it done that way on home shows. My issue with it is that it leaves an unsupported edge 4' up your wall--right where the wall can take a lot of abuse. When you do it vertically, you put the seams over a 2x4, and the vertical height of the sheets puts any unsupported seams over head height...

I sand only once. First coat of mud goes on to hold down tape with a 5" knife. Nice and liberal coat. After it goes on, I use the same blade to knock off any ridges or bumps, then put another coat on, feathering the mud out. Same thing--let it dry, knock off the high spots and ridges with the knife, and then put on a final coat, feathering it out wide with a big knife. Sand with a screen once just to get things finally evened out.

Ed Kilburn
01-04-2010, 10:22 PM
I don't like to do dry wall, my feeling is: if it's liquid and I can't drink it I don't want to mess with it. But sometimes I have too. A couple things that has made the jobs easier: butt boards, buy them or make your own from MDF http://www.trim-tex.com/installation%20instructions/Buttboard_825.pdf (http://www.trim-tex.com/installation%20instructions/Buttboard_825.pdf) ,
Level line for inside corners http://www.levelline.com/, a trick a expert dry wall guy showed me, add dish washing detergent to the dry wall mud, for coats after the first coat, and lastly hold a light at right angle to the wall to see any defects as you sand, sure you will see them after the paint is on, but before is much easier to make them right.