Painting Drywall: Do I Need to Plaster First?

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Discussion Overview

The discussion revolves around the process of painting drywall, specifically whether it is necessary to plaster the surface before applying primer and paint. Participants share their experiences and opinions on techniques for preparing drywall for painting, including the use of joint compound, primer, and the potential need for multiple coats.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants suggest that plastering the entire area is not necessary, as long as the joints and imperfections are properly filled and smoothed with joint compound.
  • There is a discussion about the number of coats of primer needed, with some asserting that one coat is sufficient while others suggest that multiple coats may be required for optimal results.
  • One participant mentions that the first coat of paint can act as a primer, proposing that two coats of paint may suffice for a small area.
  • Concerns are raised about the drying time of joint compound and the potential for cracking if applied too thickly or if subsequent coats are applied too soon.
  • Some participants recommend using a wet sponge technique for smoothing spackle instead of sanding to reduce dust and cleanup.
  • There is clarification regarding the terminology used, with some participants questioning whether "plaster" refers to spackling compound, as the two materials have different properties and handling requirements.

Areas of Agreement / Disagreement

Participants express differing views on the necessity of plastering before painting, the number of primer coats required, and the best techniques for achieving a smooth finish. No consensus is reached, and multiple competing views remain throughout the discussion.

Contextual Notes

Some participants note that environmental factors, such as humidity, can affect drying times for joint compound. There are also mentions of the aesthetic qualities of plastered versus painted drywall, indicating a preference for certain finishes based on personal taste.

Who May Find This Useful

This discussion may be useful for DIY home improvement enthusiasts, particularly those interested in drywall finishing techniques and painting preparation methods.

Saladsamurai
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Hey guys...the home improvement is coming along thanks to all your suggestions! I hope to have all these projects done before my folks come home from Florida as a surprise for them. They let me live here and pay for my education, so it's the least I can do for them!

So here's the question. I have a 10' x 4' area of wall that used to be a "window" into the living room from the kitchen. It has since been covered up with sheetrock (drywall). I have used joint-compound and joint tape along the perimeter to cover the border-gaps.

Now, I know traditionally one would "plaster" a thin layer (or multiple thin layers) over the area of the drywall and then prime/paint it.

I have seen some special primer at home depot that says it can be painted directly onto drywall. Anyone use this stuff? Do I HAVE to plaster the drywall first.

Thanks again! :smile:
 
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Saladsamurai said:
Do I HAVE to plaster the drywall first.

No. At least not the whole 4 x 10 area. You might need more than one coat, but I should think without looking at the paint that it should work. Just make sure the joints/joint tape or any screw indentations or nail holes are filled and smoothed level with the wall surface with the joint compound and sanded well, even if it takes a couple of passes to build it up, because any imperfection is magnified after painting and the goal is for it to be visually uniform.
 
LowlyPion said:
No. You might need more than one coat, but I should think without looking at the paint that it should work.
Thanks :smile:


More than one coat of the primer, right?
 
LowlyPion said:
No. You might need more than one coat, but I should think without looking at the paint that it should work.

So, if you don't plaster, you'd better ensure you prime. That's what you're saying, right?

You don't want to paint right on the wall.
 
Saladsamurai said:
More than one coat of the primer, right?

No. Only one coat of primer. I thought you were talking about primerless paint.
 
Painting will be the least amount of the work. Getting everything spiff is the biggest job - at least for me because I try to do a neat job.

As far as primer, the first coat of paint acts as a primer anyway. The primer mostly is a cheaper way to just fill the pores. I'd say you can choose to just paint it twice with the final color for a little area like 4 x 10.
 
Saladsamurai said:
Hey guys...the home improvement is coming along thanks to all your suggestions! I hope to have all these projects done before my folks come home from Florida as a surprise for them. They let me live here and pay for my education, so it's the least I can do for them!

Wow! That's really a wonderful gesture! It looks like others already have you covered on the answers to your questions. Good luck with finishing the job!
 
Thanks guys! So here is what I am going to do.

Plaster the perimeter. Prime the drywall twice. Prime the surrounding wall once. Paint twice.
 
Saladsamurai said:
Thanks guys! So here is what I am going to do.

Plaster the perimeter. Prime the drywall twice. Prime the surrounding wall once. Paint twice.

Sounds double what's needed as far as painting. Given a choice between work painting and work sanding, put the effort in the sanding. Make sure the joint compound is spread smoothly and sanded as flat as you can get it. Any ridge or blemish or groove will cast a shadow and sadly the eye is a great detector of any irregularity.

Good luck.
 
  • #10
LowlyPion said:
Sounds double what's needed as far as painting. Given a choice between work painting and work sanding, put the effort in the sanding. Make sure the joint compound is spread smoothly and sanded as flat as you can get it. Any ridge or blemish or groove will cast a shadow and sadly the eye is a great detector of any irregularity.

Good luck.

Thanks! I always prime once, paint twice. I think that the paint adheres better to the primer. I hate it when it peels
 
  • #11
It's official. I am the WORST plasterer EVERRRRR! :smile:
 
  • #12
Saladsamurai said:
It's official. I am the WORST plasterer EVERRRRR! :smile:

It's not all that easy so don't be too hard on yourself. I hope you have a scraper that is at least 4" to 6" wide to get as much smoothness in it as you can while it's malleable. Let it dry thoroughly and then sand and then go over it again with more compound to smooth out any grooves or valleys you may have left. Remember sanding off is easier to fix than leaving valleys as that requires another application and dry cycle. Patience is the key. Repeat until satisfied or totally exasperated and decide that people won't notice and that if they do ... well tough.
 
  • #13
LowlyPion said:
It's not all that easy so don't be too hard on yourself. I hope you have a scraper that is at least 4" to 6" wide to get as much smoothness in it as you can while it's malleable. Let it dry thoroughly and then sand and then go over it again with more compound to smooth out any grooves or valleys you may have left. Remember sanding off is easier to fix than leaving valleys as that requires another application and dry cycle. Patience is the key. Repeat until satisfied or totally exasperated and decide that people won't notice and that if they do ... well tough.

Good advice! Thanks:smile:
 
  • #14
The first coat of joint compound needs to dry for more than a day. As the compound dries, it shrinks a little, so if it is more than 1/4 inch deep (5 mm) it will pucker (inward) or crack. If you put the second coat of compound on before the first dries completely, the crack will show through.

It is very humid where I am, so I have to wait three days sometimes, especially if the compound is used to fill any gaps (corners especially).

If your finishing is "not so hot," and it looks like some roughness will show through the final product, then it might be a good idea to "skim" a very thin coat (1/8 inch to "vanishing") of compound over the rest of the board. Painted drywall finishes very smooth, and it will make it quite obvious where the seams are if you don't smooth them perfectly.

Also, if the rest of the wall is plastered, then it probably has some imperfections to it. These imperfections give a lot of character to walls and make them feel more human/less industrial.

Around these parts, folks are going back to plaster or skimmed drywall in new houses just for that "feel."

The best part of this is: much less sanding. You do need, however, a very wide knife: talking 12" to 15"

But, you're probably done by now.
 
  • #15
Hey Salad, try this... Instead of sanding (which makes lots of dust to clean up) try a wet sponge and a bucket of water. Wipe gently where you want to blend the spackle in as if you were sanding. Spackle will come off and fill up your sponge like it were sand paper. Don't use too much water, it'll mess up the spackle, but a damp sponge is perfect for feathering in edges between spackle and drywall and knocking out those ridges and imperfections. Rinse the sponge out as the spackle builds up on it. Might take a bit of experience but it's a lot easier/faster/cleaner than sanding.
 
  • #16
Um, I hope when talking about "plaster," on drywall, you really mean spackling compound (spackle). Otherwise, if you apply too much, sanding is going to be VERY difficult with real plaster. :rolleyes: With real plaster, any sanding needs to be done while it's still slightly moist, and the goal is to apply it as sparingly as possible. Spackle, on the other hand, is easily sanded.
 
  • #17
Moonbear said:
Um, I hope when talking about "plaster," on drywall, you really mean spackling compound (spackle). Otherwise, if you apply too much, sanding is going to be VERY difficult with real plaster. :rolleyes: With real plaster, any sanding needs to be done while it's still slightly moist, and the goal is to apply it as sparingly as possible. Spackle, on the other hand, is easily sanded.

A good power sander with 80 grit eases that concern - creates a lot of dust however - so a mask or bandanna if you must. But I think joint compound is what is being used and shouldn't be much of a concern. Proper drying is important, but not much of a problem and not all that long to wait unless you're talking about some degree of thickness. But then all that does is shrink and crack and the cracks can then be filled. Like shampoo - lather, rinse, repeat.
 

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