Bathroom Ceiling

[mikester]

Well, the last room to tackle this time around it the downstairs main bathroom. Its small. Only 5x9.
We're pulling the tub out and taking it down to the studs for the third time since we've been in the house. Since its only used by me and my wife we're going with a walk in shower.
Putting MR board on the walls. PVC bead board on the lower walls. Cement board for the shower tiles.
The big question... what else can I use for the ceiling besides drywall ? The room has one window and a Broan exhaust fan with 100 CFM but the steam from the shower has always wrecked the ceiling paint no matter what brand I used. I had the best luck with a product made by Zinsser but its been discontinued.
I wouldnt mind a PVC material but I dont think it comes larger than 4x8.
Any suggestions ?

 

[Shiftless]

I used 1/4 inch thick hardi backer board on my last bath remodel here. Tape and mud the seams.
After 15 years of daily hot showers it looks as good as new, my bath is even smaller than yours so the entire room is basically a low temperature steam room. I did the walls and the ceiling in hardi backer board with porcelain tile halfway up except in the shower where the tiles go all the way up to the ceiling. Tile floors too of course. Half inch hardi board on the walls and floor.

 

[rlitman]

I used Durock board on all of my bathroom. Rough side facing the tile, smoother side down on the ceiling. After spackling smooth (because the cement board simply isn't ready for paint), primed with Zinsser Mold Killing Primer, and finished with semi-gloss paint with M-1 mildewcide mixed in.

With semi-gloss and additives, I haven't had issues. Any flatter of a paint and I've had problems down the road.

 

[mikester]

I used 1/4 inch thick hardi backer board on my last bath remodel here. Tape and mud the seams.
After 15 years of daily hot showers it looks as good as new, my bath is even smaller than yours so the entire room is basically a low temperature steam room. I did the walls and the ceiling in hardi backer board with porcelain tile halfway up except in the shower where the tiles go all the way up to the ceiling. Tile floors too of course. Half inch hardi board on the walls and floor.

I used Durock board on all of my bathroom. Rough side facing the tile, smoother side down on the ceiling. After spackling smooth (because the cement board simply isn't ready for paint), primed with Zinsser Mold Killing Primer, and finished with semi-gloss paint with M-1 mildewcide mixed in.

With semi-gloss and additives, I haven't had issues. Any flatter of a paint and I've had problems down the road.

So both of you guys used cement board instead of drywall throughout the bathroom ? I know its going to be used under the tile in the shower and on the floor over the plywood but I never heard of anyone using it for ceilings and walls. How do you finish the corners and How is it to nail in trim ?

 

[Shiftless]

So both of you guys used cement board instead of drywall throughout the bathroom ? I know it’s going to be used under the tile in the shower and on the floor over the plywood but I never heard of anyone using it for ceilings and walls. How do you finish the corners and How is it to nail in trim ?

Since I ran tile up the walls for 3 feet, I didn’t need baseboard trim. Where the walls meet the ceiling, I didn’t use any trim. I just treated the room as if it was drywalled. Tape and hot mud on the joints and in the corners. No tapered edges like Sheetrock so you have to spend extra time on the flat joints. BTW, no nails... I used the prescribed screws.

 

[nmk_61802]

Not really a question for the OP, but for those who say they used cement board....If you are skim coating with drywall compound, how is that better than water-resistant drywall? I would argue that it should actually be worse. The entire finished surface is covered with a water soluble product and is mold food. It relies on the paint to protect it. At least with WR drywall the paper portion is covered with water resistant coating.

This is a genuine question, just trying to understand the thought process behind this.

 

[Shiftless]

This is a genuine question, just trying to understand the thought process behind this

The building inspector required cement board on walls and ceiling. I used hot mud to minimize the risks you described and after 15 years, it has held up well. The original paint is still there and looking good. Quality primer and paint is important.

 

[mikester]

The building inspector required cement board on walls and ceiling. I used hot mud to minimize the risks you described and after 15 years, it has held up well. The original paint is still there and looking good. Quality primer and paint is important.

What the heck is hot mud ? Never heard of that before. Im in NY. Im sure some things are done differently. Even as far as building codes.

 

[Shiftless]

Sorry, I thought it was a common term.
You buy dry powder and mix it with water to get drywall compound. It generates heat by the chemical reaction. You can buy some that hardens quickly and other mixes that take longer. Your choice depending on how big your job is and how quick and skilled you are.

 

[Shiftless]

From the web…

”Hot drywall mud, also referred to as "hot mud" or "quick-set joint compound," is distinct from regular joint compound primarily because of its accelerated drying time. While standard joint compounds can take up to 24 hours or more to dry, hot drywall mud sets much faster, typically within 20 to 45 minutes.”

 

[nmk_61802]

Hot mud sets by a chemical reaction vs premix's drying by the water in the mixture evaporating. Because it is a setting compound it is generally more water resistant than premix, but still somewhat water soluble. Typically it should be used for filling and initial tape coat, and is not used for skim coats due to its difficulty to sand.

 

[jkuro]

Small ceiling fan works wonders. Turn it on after your done and let it dry out the room. Mold is a thing of the past.

Regair Ceiling Fans with Lights, DC Motor 22 inch Low Profile Ceiling Fans with Remote Control, Reversible Blades Small Black Flush Mount Ceiling Fan for Kitchen Bedroom Dining Room Living Room https://www.amazon.com/dp/B0BY27MYD8?tag=atomicindus08-20

 

[mikester]

From the web…

”Hot drywall mud, also referred to as "hot mud" or "quick-set joint compound," is distinct from regular joint compound primarily because of its accelerated drying time. While standard joint compounds can take up to 24 hours or more to dry, hot drywall mud sets much faster, typically within 20 to 45 minutes.”

Never heard of the term but now I know exactly what you mean. USG makes it. Ive used it for small repairs before Ive painted walls in my house. I usually use the 20 minute stuff.

 

[Shiftless]

Small ceiling fan works wonders. Turn it on after your done and let it dry out the room. Mold is a thing of the past.

Regair Ceiling Fans with Lights, DC Motor 22 inch Low Profile Ceiling Fans with Remote Control, Reversible Blades Small Black Flush Mount Ceiling Fan for Kitchen Bedroom Dining Room Living Room https://www.amazon.com/dp/B0BY27MYD8?tag=atomicindus08-20

Ceiling fans will stir the air around but will not on their own remove humidity. If you leave the door open and the rest of your house is dry, the ceiling fan will move the moist air from the bathroom and mix it in with the rest of the air in your house.
To remove the steamy air from a bathroom, you need an exhaust fan to move it outdoors and replace it with air from your house.

We have 2 bathrooms and each one has a Panasonic exhaust fan controlled by a timer switch on the wall. Many people recommend this set up.

 

[PoorUB]

My bathroom is all sheet rock with typical dry wall mud from buckets and zero moisture issues. I did add a timer to the bath fan ad let it run after a shower. I typically run the fan for an hour total. Being a guy a long shower might be ten minutes.

 

[nadogail]

My workshop toilet room walls are covered with FRP, there is no actual ceiling the walls extend to the joists above it and were counted as an unglazed interior window opening into the shop itself.

If FRP Is tough enough for fast food restrooms, it is good enough for my shop.

 

[CraigStu]

I'd look at pvc trim boards. their dimensions are perfect and they don't warp so putting them up side by side you would get a look kind of like shiplap but it should never change. They are usually white so no need for paint. Also they usually have one side smooth and the other a slight woodgrain so your choice which to use.

 

[Norcal]

My workshop toilet room walls are covered with FRP, there is no actual ceiling the walls extend to the joists above it and were counted as an unglazed interior window opening into the shop itself.

If FRP Is tough enough for fast food restrooms, it is good enough for my shop.

I had FRP around the, tub/shower walls because of a window, it held up well, the moisture resistant drywall behind it crumbled, been replaced with 3X5 subway tile. The Kerdi was more expensive then the tile.