Does the color of latex caulk matter when it will be painted over?

[snowjim]

Hello,

I'm going to apply quite a bit of latex caulk on the ceiling (between each tile), but I just noticed that the one I have is a Bostik dark gray. The ceiling will be painted white after the caulking with Beckers paint in 2 layers. Does the color of the caulk matter? Should I make sure to go and buy a white one? I know from past experience that dark undercoats can show through, but maybe that's only when the paint has low pigment?

The alternative, as mentioned, is to go and buy white, and I have the following brands to choose from: Tremco, Illbruck, and Casco.

 

[verktygsgurun]

You should not have any latex caulk at all in the ceiling between the panels. (Assuming plasterboard)

 

[Jonaasa]

As stated above: assuming gypsum boards. They should be spackled with medium filler and paper tape. You need to be more specific about what kind of boards they are.

 

[snowjim]

The panels consist of thin (2mm) masonite, a cavity with some type of paper, thin (2mm) masonite again, and this is attached to a solid frame. Each panel is approximately 150 x 40 cm. The joints are slightly beveled, forming a pattern on the ceiling.




The same ceiling runs throughout the villa from room to room, and you can see in several places where the panels have a small (max 1 mm) gap (black) between them. My current thought before painting is to apply a very small bead of latex sealant to prevent the paint from cracking here again.


http://i.imgur.com/0YztaiY.jpg

 

[snowjim]

Chose to buy white sealant, you never know if it will crack and the color will give way so you can see the joint underneath. This ceiling has been there since the 70s, so it shouldn't move very much anymore, but it's better to be safe.

Now the sealants are in place and it looks really good, how it works in the long run remains to be seen, but it's better than just painting without latex sealant.

 

[f91jsw]

It will most likely crack over time. I have dealt with many such ceilings and you can never avoid cracks in the paint in the long run. You just have to live with it.

 

[verktygsgurun]

I thought you would fill to get a completely smooth ceiling. So in your case, you have chosen correctly. It's good to know that there are new latex joints with up to 25% flexibility instead of the normal 5%.

 

[f91jsw]

Do they withstand 25% even after 10 years? Regular latex sealant becomes almost completely hard over time.

 

[snowjim]

The joint I used absorbs movements up to 12.5%. If it holds up over time, we'll see, but it can't be worse than not using it at all.