bathroom paint + humidity
#1
bathroom paint + humidity
Since I bought my house I notice something weird with the bathroom ceiling.
The paint seems to blister and crack over time.
Last summer I sanded, patched and smoothed out the ceiling, then primed and re-painted.
Over the past few months I have noticed it is starting to do the same thing again.
When the humidity rises, the paint seems to grow, when humidity goes back down the paint goes back to normal.
This bathroom is quite small, but is also the only one in the house.
A few years ago I installed a new higher flowing ceiling fan to help keep the steam from the shower to a minimum.
Window open, fan going, doesn’t seem to make much of a difference what I do.
Am I getting the wrong paint? I did KILZ last year after sanding and all that, then did a bathroom/kitchen paint with mildew resistance and primer included.
After 15yrs here, I’m trying to prep to move, but I’d like to figure out what I can do with the bathroom to stop this issue.
The paint seems to blister and crack over time.
Last summer I sanded, patched and smoothed out the ceiling, then primed and re-painted.
Over the past few months I have noticed it is starting to do the same thing again.
When the humidity rises, the paint seems to grow, when humidity goes back down the paint goes back to normal.
This bathroom is quite small, but is also the only one in the house.
A few years ago I installed a new higher flowing ceiling fan to help keep the steam from the shower to a minimum.
Window open, fan going, doesn’t seem to make much of a difference what I do.
Am I getting the wrong paint? I did KILZ last year after sanding and all that, then did a bathroom/kitchen paint with mildew resistance and primer included.
After 15yrs here, I’m trying to prep to move, but I’d like to figure out what I can do with the bathroom to stop this issue.
#2
Forum Topic Moderator
How old is the house? I assume there is latex enamel on the ceiling now but is there oil base enamel under it? If a solvent based primer isn't used when switching from oil enamel to latex adhesion is always suspect 
You said 'ceiling fan' did you really mean an exhaust fan?

You said 'ceiling fan' did you really mean an exhaust fan?
#3
House is old, not 1800's, but probably 30's or so? Nobody could really find any info on it when I bought so they went with 1950.
The previous owner painted every room the same color, grey, must have been a special on grey paint.
What he used also did this then, but if he used the mismatched type, then it was already set to fail. I just re-did it trying to do it by cleaning/sanding/priming, etc...
I did mean exhaust fan yes, sorry.
The previous owner painted every room the same color, grey, must have been a special on grey paint.
What he used also did this then, but if he used the mismatched type, then it was already set to fail. I just re-did it trying to do it by cleaning/sanding/priming, etc...
I did mean exhaust fan yes, sorry.
#4
Forum Topic Moderator
Oil base enamel was used in kitchen and baths along with woodwork into the 70's with some using it longer. Which Kilz did you use? Oil base Kilz should adhere decent although if it's applied over paint that doesn't have a good bond with the underlying paint .......
I never use the latex Kilz but it's been reported to have adhesion issues 
The best plan of attack would be to scrape off all the loose paint you can, sand and then apply a coat of oil base primer. Finish with a bath rm enamel.
be aware that the original oil base paint might be lead based!


The best plan of attack would be to scrape off all the loose paint you can, sand and then apply a coat of oil base primer. Finish with a bath rm enamel.
