Wall and Ceiling Repair Q&A
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Some of the screws or nails in our wallboard are "puffing out";
that is, there are little raises in the walls. What is the best way to fix
these. The house is about four years old and was constructed from during the
winter/spring of 1994
The defect you describe is fondly referred to in the trade as "nail
pops". After a house is built, the wood framing tends to lose moisture once
it is no longer exposed to the elements. The wallboard, which had been firmly
nailed or screwed to these wall framing members, or studs, suddenly has a slight
gap behind it… gasp… the wood has shrunken away! The nail pops occur when
either normal seasonal shifting in the house or the touch of a human hand (or
head… or foot) causes the wallboard to move towards the stud. The nails, of
course, remain in position. The compound covering the nail heads is pushed
outwards, forming the slight rise, or "pop".
To perform a repair you need to do two things. First, scratch the wallboard
compound from the head of the fastener to see if it is a nail of screw. If it is
a nail, hammer it back in. If it is a screw, turn it until is below the level of
Next, you must add additional fasteners to stabilize the wallboard so that
the "pop" doesn't recur. Simply driving in the old nail/screw is not
sufficient. Press the wallboard solidly against the stud and install one nail or
screw a few inches above the pop, and another a few inches below it. It is not
necessary to remove the original fastener… just drive it in so that it is
below the level of the wall. Once the wallboard is solidly fastened, cover all
the nailheads with a coat or two of drywall compound, sanding as necessary after
the final coat dries.
Sometimes, this can become a "Rube Goldberg"... fixing one nail pop
causes another to appear. This means that there has been excessive shrinkage in
the wall studs, and you will have to do more banging, screwing, and patching to
get the job right!
I need to do some patches on my old plaster walls, and discovered that in
some areas the plaster has pulled away from the lathe... the wood strips that it
locks into. Do I have to tear the wall down, or is there an alternative repair?
There are a number of ways to approach this repair, depending on the severity
of the problem. One way to repair a small area of plaster that has released from
the lathe is to chisel out the loose plaster and replace it with wallboard. It
is generally acceptable to leave the lathe in place and screw the wallboard
directly to it as long as you can screw the wallboard firmly to it. If the lathe
is damaged so that there is no screwing surface (angry feet through walls can
cause this interesting decorative effect), cut the wall open just wide enough to
expose a wall stud and bridge the gap with the wallboard.
Instead of cutting the stud-to-stud opening, you could instead attach 1x2 or
larger wood strips across the hole, screwing through the plaster into them so
that they bridge the opening and give you a strong nailing surface. You may have
to use a masonry bit to predrill the holes for the screws and make a slight
depression in the surface of the plaster with a larger masonry bit to
"countersink" the screw heads. You don't want the screw heads to show!
Get the feeling that working with plaster is not as easy as working with
Cut the wallboard to match the shape of the plaster hole, leaving about a
quarter inch open around the perimeter of the patch. Use wood shims to raise the
level of the wallboard so that it is slightly lower than the level of the
plaster. If you are lucky a thin pre-made wood product such as lattice might do
the job. If not you will have to cut custom wood shims on a table saw.
Then again, shimming might not be necessary depending on the thickness of the
plaster. If standard 1/2" wallboard is too thick and produces a level or
raised surface, use 3/8" wallboard instead. The reason I suggest having the
wallboard slightly beneath the surface of the plaster is because plaster walls
are not always of uniform thickness. "Picture perfect" wallboard will
almost never make a good patch without some creative filling.
Slightly dampen the plaster on the perimeter of the patch and the wallboard
with water. Apply a stiff mix of Plaster of Paris to the 1/4" gap, pressing
it deeply into the gap and also pressing it against the old plaster. Plaster of
Paris expands as it dries, filling the opening tightly. It will also seal the
damaged edges of the plaster so the final finishing will wallboard compound
won't dry too quickly. Plaster of Paris sets quickly so don't dilly dally
around! This is why I use it instead of slower drying patching plaster. To avoid
having to sand the Plaster of Paris (which can be done but is a pain), make sure
the level of the plaster is below the level of the finished surface.
Let the plaster set hard... usually less than a half hour. Now you can begin
the fun and artistic part of this repair... smoothing the patch. Apply a coat of
wallboard compound with a wide wallboard knife over the entire patch, bringing
it slightly above the level of the original plaster and "feathering"
the repair out beyond the patch. Don't expect a perfectly smooth surface with
the first coat. Allow a day for the first coat and the plaster to dry. You will
use multiple coats and a final sanding to obtain a perfectly smooth surface that
will blend your patch into the rest of the wall.
Sometimes if a plaster surface is fairly solid but has loosened from the
lathe, it can be solidified by reattaching it to the lathe, or
"keying" it. This is done by drilling a number of holes in the plaster
with a masonry bit and finishing them with a cold chisel so that spaces between
the lathe are exposed. Space the holes a foot or so apart, vertically and
Dampen the old plaster slightly and press Plaster of Paris into the hole so
that it pushes through the lathe. You might want to put pressure on the wall
while the plaster dries to keep it firmly against the lathe. You should keep the
wall absolutely immobile overnight so the plaster becomes extremely hard. Once
fully set, it will bind tenaciously to the lathe, holding the wall firmly in
place. Finish repairing the holes with wallboard compound.
As an alternative, you could also screw the wall back against the lathe using
2" drywall screws. This method is less sure than the plaster key method
because you have no way to know how strongly each screw is holding in the lathe,
especially if the lathe is old dry wood. However, locating the wall studs and
adding additional screws through the plaster into them can't hurt!!
If the newly firmed wall has developed unsightly "spider web"
cracks, you can apply a special wallpaper to restore the surface to pristine
smoothness. Check with your local paint/wallpaper store for the correct product.
Of course, using standard wallpaper will also mask these imperfections if you
prefer to have this big job end a little more quickly... without the finish
painting and seam covering!
We recently had some water damage on the ceiling of our
bedroom. It appears
that some mold/mildew is on the surface. Here is what I think I
1. Fix the roof to stop water from entering the home
2. Remove damaged (wet) insulation from the attic
3. Remove damaged drywall from the ceiling
4. Clean any exposed wood with bleach to kill the mould/mildew
5. Allow time to dry thoroughly
6. Install new drywall
Am I on the right track?
You are "on track" and your plan seems well thought
out! You should pay special attention to steps (3) and (4).
IF the drywall turns out to be solid after it dries, you might
not have to replace it. Killing the mildew with bleach and priming
with Kilz or an equivalent oil-based stain killer should give you
a good, paintable surface. If the drywall is solid... but a little
"bumpy" or uneven because the facing paper is loose...
score the paper with a utility knife (don't cut deeply... just the
paper!) and peel it off. Then use drywall compound to level and
smooth the surface prior to priming/painting. Or just use compound
to smooth the area if the defect is really minor.
It isn't absolutely necessary to clean the wood, even if it has
mildewed. Once the source of the moisture is gone and the wood
dries out, the mildew will cease to grow. It is true that mildew
spores can remain alive for long periods of time with no water,
but if you fix the leak there should be no recurrence of mildew
growth. Of course, if you have any "hygienic" or
allergy-related reasons to clean it please do.
I like to use the pre-mixed mildew-killing sprays with chlorine
bleach that are available for bathroom use. They are very strong
and effective. Since you may be spraying upwards, be careful to
protect your eyes and don't breathe the spray. You shouldn't need
a respirator, but if you think you might inhale the mist use a
dust mask, which will at least catch the droplets. Though the
instructions call for rinsing the treated surface, you need only
to wipe it with a damp sponge to get off any loose dust,
especially since you are going to prime the drywall surface and
repaint. I have not found the dried bleach residue to affect the
adhesion of Kilz at all! Not much does!!
Also, don't worry about rinsing the bleach from the wood... the
action of the bleach will be short-lived and will not cause any
damage to the wood if you don't rinse it. You might want to sponge
off any excessive amounts of mildew if you have grown a
fungus-forest up there!!
I am looking for tips on how to deal with nail heads popping out of drywall. The wall is in good shape and really doesn't need to be replaced, but I
don't want go through the time expense of painting the wall only to see the
bumps created by the nail heads pushing out under the dry wall tape. This
is a 25 year old colonial that seems to have been constructed pretty well
but some of the drywall work is not so good.
Pound in the offending nail. Then, put a nail or, preferably, a drywall
screw above it and below it into the stud, spaced a few inches away. Patch
and paint. If your problem is under the tape, work right through it! It is
unnecessary to cut the tape away unless it has loosened from the wall.
Then, you should bend the tape up, slather a little wallboard compound
underneath it, and press it back into place.
I need help as to how to go about repairing a hole in the wall. Well, not
really a hole. It's more like a dent caused by a piece of furniture that banged
against the wall. I'm not sure exactly what kind of wall it is, but it's fairly
sturdy. I know the house was built quite
recently (early 1990s) if that helps.
MM from Oneida, NY
When you say dent, I say drywall… or gypsum panel… or wallboard… all names
for the gypsum-based, paper-covered construction material of choice for modern
walls and ceilings. (SHEETROCK©, another oft used
name for drywall, is a registered trademark of the USG Corporation.) Plaster… a Portland cement-based product… doesn't dent
because it's very hard. However, with enough "persuasion" it can
break or crack!
Small dents or defects in walls are easy to fix with any of the patching
compounds available for wallboard, regardless of the actual type of wall. Of
course, larger repairs in plaster will need a special setting product made for
For drywall, though, the easiest products to use are the premixed,
lightweight spackling compounds, available in small plastic tubs or gallon
sizes. Regular or lightweight wallboard compound is also an excellent choice for
this sort of repair, but since you must purchase a gallon minimum it makes
little sense unless you plan on going on a "denting spree"! Besides,
once the seal on the container is broken, drywall compound does tend to dry out
in the can over time. A year from now when you need it again it just might be
somewhat lumpy and unusable.
All you need to do is apply it to the dent with a three inch wide flexible
putty knife for any dent up to that width. Use smooth strokes to fill the
crevice and to be sure that the spackle has stuck to the wall. Be neat and don't
build up the spackle. When it is fairly smooth, stop and walk away. It is very
difficult to get a perfect fill the first coat. The larger the repair, the
harder it is! So go have a Perrier, watch the game and give the spackle some
time to dry… at least four or five hours. I know… the labels say that they
can be painted over almost immediately. That is true for very small holes, but
in the case of a dent or larger fill, the product will smear if not given
adequate drying time.
Sand the patch lightly with a 120 grit sandpaper to smooth it off. If you are
satisfied with the repair, you can proceed to touch it up with paint… no need
to prime these products if you are using a high quality latex wall paint. But if
the patch is not full and level, apply a second coat of lightweight spackle and
repeat the process.
I make the distinction between the "lightweight" spackles and the
old fashioned plain spackle. Good ol' plain spackle… which comes either
premixed or in a powder form… was designed to be used primarily on small
plaster repairs, not on softer, paper-faced drywall. In my experience, I have
found that spackle tends to dry so hard that it is almost impossible to sand
without causing collateral damage to the drywall! Because of this hardness,
there have been a few occasions where I have found it easier to just cut out the
spackle rather than waste time sanding it. So if you ever use plain spackle, be
very sure that you smooth it carefully and use multiple coats instead of
building up the repair with one heavy coat.
I need to do something to repair a problem with my plaster walls. The
current finish is smooth, but all the walls have cracks that span the walls and
in some areas the plaster has "egg shell" or a maze of fine cracks. We both work
full-time, so I would like to take the easiest way out that would be a good fix.
What do you suggest. PS. I can wallpaper, paint, patch cracks,etc. The house is
about 70 years old.
VJ from Danville, VA
Those spidery cracks are typical of old plaster and have been caused by years
of stress on the walls. (I feel that way sometimes myself!) Simple patching is
not practical since there are so many cracks and they are too fine to hold a
patching compound. The amount of labor you would need to invest to open the
cracks up sufficiently for patching is better spent elsewhere, such as intense
In my opinion, the best repair for you would be to cover the walls with a
special type of wallpaper designed to restore the wall surface. Any paint or
home store can get it for you though most stock it. Do all minor repairs, such
as hole filling, before applying the paper. The better the smoothness of the
underlying wall surface, the better the final results will look. Prime all
repairs with Kilz or another stain killing primer before papering. Ask the paint
store for recommendations for sizing (a special type of primer to prepare walls
for wallpapering) and the appropriate paste… unless the paper is pre-pasted!
Those spidery cracks are common and annoying which is why this wallpaper
product was developed. Unlike patching compound, the paper will flex with the
walls and remain crack-free for years. The best part is once the paper is
applied and painted, your walls will look like new. You may treat the seams with
a light coating of drywall compound, sanded smooth, to make them invisible. Of
course, you must prime all the walls again before painting with your finishing
After preparing a seam between two pieces of drywall with tape and compound,
I found that I could still see the mud line after painting. What can I do to get
rid of the line?
Technically speaking, all taped seams should be smooth and dust-free before
priming and painting. Once painted, it is virtually impossible to sand them
smooth regardless of the type of paint used. This is a common aesthetic problem
and not just for amateurs... I have seen many pro jobs that were left in a
somewhat rough state for the painters. Sometimes lighting conditions make it
difficult to see how smooth the joint is until after painting, where the more
uniform color showcases the defects.
But never fear... it's not too late! I suggest putting a broad skim coat of
wallboard compound over the rough area, let dry and sand smooth. No wall
preparation is necessary unless you used a semi-gloss paint. Then I would suggest
a light sanding of the paint with a 120 grit paper before applying the fresh
If there are still uneven areas, touch them up with another skim coat of
compound. Sand off any roughness and use a damp sponge to remove any dust and
also to smooth down any sandpaper lines of small defects. This additional TLC
(tender loving care) should make the joint smooth as a baby's behind!
There is one quirk with some drywall tapes. Some have an "accentuated"
fold line down the center which can stand out if not covered with an adequate
layer of compound. So I routinely install drywall tape with the high-side
of the fold line towards the wall. This would be the same direction you
would install the tape in an inside corner... except you don't fold it!
I recently took down some fake wood beams on my ceiling. Now I find that
there is a "raised" area of paint around where the beams used to be. I guess the
ceiling was painted a few times after the beams were installed. Do I need to
fill this defect with joint compound or can I blend compound in with the new
paint to give it more hiding ability?
Unfortunately, paint does not have enough thickness to mask the painted
"outline" of the beams you removed. The line will stick out like a sore thumb.
Adding joint compound to paint is an time proven and inexpensive way to add
texture to a ceiling or wall but will not give the coverage you desire, either.
So it is essential to use wallboard compound to smooth out the paint level.
First, try to remove any raised ridges or paint with a scraper, sandpaper or
razor knife. This way you will use less compound and thus have less possibility
of a visible rise in the wall at each of these repairs. Then, apply enough
compound to completely cover the defect, "feathering" the edge of your repair
out at least 6-10" outside the perimeter of the repair.
After the first coat dries, sand or scrape off any peaks or lines in the
compound and apply a second coat, again feathering it out a few inches beyond
the first patch. Sand the repair smooth. Sometimes a third coat is necessary,
depending on the thickness of the fill and the amount of shrinkage in the
compound. I prefer to use "light weight" joint compound for these repairs. It
handles somewhat like standard joint compound but has less moisture and more
body. It hardly sags at all in thick applications and shrinks very little,
making many three-coat jobs two-coaters, and some two-coat jobs one-coaters! A
real time saver in a can!
The enemy of all wall or ceiling patches is shadows. Low profile patching is
the goal... so keep the compound as thin as possible while still masking the
I've repaired "nail pops" in my bathroom numerous times. I wait until the
repair is dry, sand, and paint (latex). It usually looks great.... until a month
later when the repair cracks. The bathroom is used for showering, so it gets
mighty humid there. Do I need to use special filler? I've tried various
"spackling compounds," even outdoor ones in hopes that they would be more
moisture proof. Or should I seal the repair somehow?
You appear to have done the cosmetic repair correctly. What you haven't done
is solve the underlying problem… the wall is moving! First, a nail pop primer…
nail pops are visible dimples in the wall over the wallboard nails or screws.
This is caused by movement in the wall due to a space between the wallboard and
the wood wall studs. This can happen for two reasons… shrinkage in the wood or
improper nailing/screwing. This is a common and annoying problem during the
first few years in new construction, so much so that it has become common for
contractors to use construction adhesive on the studs to keep stud and wallboard
Though some nail pops proudly display themselves without warning, many lie in
wait until someone leans on the wall… oops… or during routine repairs such as
picture hanging or even painting. The wall suddenly moves, causing the nails to
push on the wallboard compound covering them. The pops appear like mushrooms on
a damp lawn… as if you didn't have enough work to do!
Simply repairing the visible wall damage… the "pop" or dimple caused by the
movement of the wall… is not enough. The pop will reappear… guaranteed… unless
you take steps to tighten up the wallboard. Some folks think they can take the
easy path and simply bang in the nail or tighten the drywall screw. Sorry…
usually not enough. The best repair is to install a drywall screw three inches
above and below the pop while pressing the wallboard against the stud. This
action both tightens the wall and gives support to the weakened drywall around
Be prepared (not scared, just prepared) for a few more nail pops to appear
along the same stud (or even in adjacent studs) as you do this repair. By
disturbing the wall, you are arousing the nail-pop demon! Boogah! Boogah! Get
this little devil under control by doing the same aforementioned procedure on
all the subsequent pops and I can give you a 99% guarantee that this is one home
repair you will not have to repeat!
I recently got involved in a renovation project. Well, someone
decided it would be cool to put contact paper onto the walls. The
walls are plaster of some sort and underneath that cement. Is
there a special method of getting rid of this? Will conventional
used for wallpaper removal work?
Contact paper? Oh boy! The adhesive on contact
paper is very strong and very difficult to remove. Because the
adhesive is also water-resistant, standard wallpaper removal
products will not have any effect.
Instead, use a hair dryer to heat the contact paper. The heat
will soften the adhesive and make removal much easier. Start at a
corner and pull on the paper as you warm it. The warmth may also
restore a little of the flexibility to the plastic so it is less
likely to split as you remove it. Be patient and take your time or
you may do incredible damage to the walls... especially if they
are paper-faced wallboard!
Once the contact paper is off, you can use an adhesive remover on the walls
to strip the adhesive residue, if any. Use a "citrus"-type adhesive
remover rather than a solvent-based one since you may soften or even remove the
paint with the solvent. Prime the walls before repainting to assure proper
finish paint adhesion.
I had a guy fix protruding nail heads... a.k.a. nail pops... on my ceiling. I
bought some paint to touch up the repairs, but the touch ups stand out because
they are whiter than the ceiling. Is there any way to tone down the whiteness so
that it blends better with the rest of the ceiling? (And I thought my ceiling
I feel your paint! Errr... pain, that is! Isn't it amazing how "white" a
ceiling can seem until you put a few dabs of fresh paint on it?
you, white is a relatively easy color to work with. Go to your hardware or paint
store and purchase a tube of black pigment. Add a very tiny amount to some of
your white paint and mix it well. With a little experimentation and lots of
patience, you should be able to find a shade of "off white" that more closely
approximates your ceiling's current condition.
I have a drywall ceiling above my patio deck that had a
plaster-like texture. The texture was all falling off, so I
scraped it clean and painted it with a white outside paint.
I have found white texture paint and would like to put some
texture back on the ceiling. The problem is that this paint is for
interior use only.
Can you put interior paint outside if it is going over a coat
of exterior paint? I can't find any ready-made ceiling texture
paint for outdoors.
TD from California, MD
Most of the textured surfaces you see outdoors are stucco, a
Portland cement-based texture coating that is suitable for inside
or outside use. The plaster-like texture paints, though, are not
rugged enough to withstand outside exposure. Exterior paints have
certain qualities that allow them to stand the rigors of the
weather... chemically-enhanced mildew resistance, moisture
resistance and sunlight resistance. Texture paints tend to give a
soft surface with some porosity and virtually no mildew
Since stucco is not designed to adhere to drywall, I wouldn't
recommend using it for your application. However, all is not lost.
Apply your interior texture paint... but once it is completely dry
apply a coat or two of exterior paint right over the top of it!
You will still have the attractive texture, but the exterior paint
will act as a barrier to the limited exposure to the weather your
ceiling will have. Then you have all bases covered... and the
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