# Drywall around fiberglass shower unit



## mms

Which method in attached image is better?

Method 1. Cutting a groove in back of drywall so drywall bears correctly on last stud
or
Method 2. Simply laying drywall atop the shower flange allowing drywall to bend and sit slightly above the last stud.


Note that the attached sketch is not to scale.


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## The Coastal Craftsman

i normally fur the wall out a little. I used to cut the drywall edge away a little but the time i took to cut a few strips was neater and quicker.


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## dave_dj1

^^^^^^
ay yup


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## cpuhrmann

We just drywall to the flange and prefill the gap with hot mud and tape to the tub.


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## Marven

I use cardboard drywall shims. Home depot carries them now. Menards has had them. Two layers on the stud close to the shower and 1 layer on the next stud out. Nice taper.


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## Sir Mixalot

1/4" drywall then add your 1/2" over that. :thumbsup:


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## kubie

cpuhrmann said:


> We just drywall to the flange and prefill the gap with hot mud and tape to the tub.


thats what our drywaller does also


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## Big Shoe

Nobody ever thinks about it until the drywall guy shows up................................butt and mud time :thumbsup:


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## greg24k

I haven't done a fiberglass shower unit in a while... But when we use to them, we would apply silicone to the ﬂanges and install water-resistant wall material with the paper-bound edge or we would use plastic drywall end trim over it and leave 1/8" space between Sheetrock and finished shower surface, and then you tape the wall and apply bead of caulk along the perimeter.


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## mms

Thanks guys.


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## blacktop

Though It's not the D/C job to shim out the tubs:whistling I could see how this product would work nicely.. http://www.all-wall.com/Categories/Drywall-Shims/Drywall-Shim-Roll.html


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## mms

Shimming out the drywall is not an option for me as I will introduce a host of other problems elsewhere in my washroom reno.

I will go with either cutting a 1/4" X 1" continuous groove on backside of drywall as in Method1 picture or
stopping drywall at the fibreglass flange and filling the entire cavity with hot mud as in Method2 picture.

I'm not familiar with the term "HOT MUD", could someone please explain.

Also could someone explain pros & cons of both methods, so as I can make an informed choice.


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## blacktop

I wish they would fur the walls out for the flange ..But It's a rare occasion .
We stop the rock at the flange ..I then pre-fill the void with 20 min [a fast setting compound not fast drying!] Most times it takes two pre-fills to level out. I then tape around the shower tub and finish out with a/p 2 coats over tape cut tight.. IMO It's a whole lot of work for nothing!!!
But It's the only way to keep things ''looking'' square. It also keeps the base at the bottom of my tubs/showers flat to the wall. no ski slopes.

hot mud Is a fast setting compound It comes in 5.10.20.45.90 etc.. min set setting times. A powder mixed with water. It will not cure in its setting time! But it is the best to use on heavy fills .


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## mms

Thanks *blacktop*

Just so I understand:

1. hot mud in flange cavity as I show in my sketch (ie level with drywall)
2. tape - half tape width goes on drywall half tape width goes on hot mud
3. mud over tape using conventional mud

The hot mud will "bond" to the slick acrylic surface of the shower flange?

Will my back-grooving method also work, or will it cause other problems I am not aware of?
I ask because it would be less taping & mudding for me.


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## blacktop

mms said:


> Thanks *blacktop*
> 
> Just so I understand:
> 
> 1. hot mud in flange cavity as I show in my sketch (ie level with drywall)
> 2. tape - half tape width goes on drywall half tape width goes on hot mud
> 3. mud over tape using conventional mud
> 
> The hot mud will "bond" to the slick acrylic surface of the shower flange?
> 
> Will my back-grooving method also work, or will it cause other problems I am not aware of?
> I ask because it would be less taping & mudding for me.


 1. yes
2. yes
3.yes 

The hot mud will stick well enough . The right way would be to fur the wall out level to the flange . So the rock sits tight to the lip. But your method should work just fine imo.. The thing about cutting to the flange then using a filler 3/8 or 1/4 depends on the frame / how wavy is the flange . 

on a side note...Always use w/p wallboard around shower tubs .
Always caulk around shower tubs after final paint or tile etc... Moisture Is drywall's worst enemy !!! 

Check out Trim Tex . com They have some fun stuff there for shower tubs.

The back grooving seems like allot of work ..will it bust? [blow out] If so you will still end up with lots of pre-fill. JS..


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## mms

Thanks again *blacktop*

I have a window on one of the walls the corner shower unit is against.
If I use fur-out method, my drywall will be 1/8" to 1/4" beyond window frame, another problem as I will somehow have to fix window frame.

This one week bathroom reno is now at the three week point and still counting. I don't mind the extra time as long as everything is done correctly.

Yes I have purchased water resistant drywall (green board).

Does Home Depot sell this hot mud, or is only available to the professionals?

Are the drywall shims to fur-out a specialty product?

Your answer to my back-grooving option seems a valid point.
Are you talking about busting during drywall installation or after drywall has been finished/painted and in use at some point down the road?

The only reason I favour the back-grooving method is it seems like it will be easier for a non-pro (namely me) to mud and make smooth,
as there will be only a tiny crack to fill (if any) because as you say, silicone caulk should be applied.


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## Texas Wax

mms said:


> Thanks again *blacktop*
> 
> Are the drywall shims to fur-out a specialty product?


No, they are (should be) used in many wallboard applications. Home depot, Menards or any drywall supplier will stock. They come in boxes of a couple hundred. A bit pricey for one job tho. They have many more uses beyond drywall....but you have to buy them to understand how to use them LOL


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## sheetrock_22

This may help. http://www.trim-tex.com/product_catalog.php?cat_display=viewcategory&catid=28


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## Spencer

I was taught to use durabond (brown bag) instead of easy sand (white bag) on larger voids. Both are "hot mud" but you don't want to try and sand durabond. Dries hard as a rock.

I hate when guys run the drywall over the flange. Looks like crap and it sucks to trim around.


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## TheBuildingFirm

Why not stop the drywall at the flange and run tile to cover the flange gap.


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