New bathroom question (drywall, plumbing)

[eblend]

So I am doing my basement and am about to do my bathroom, but got a couple of questions.

1. I want to do tileing around bathtub up until the shower head and was wondering what the code states about the type of board to use. I understand that I should probably use those cement boards as the backing, but how do I make the transition from rockboard to drywall, or is all of the rockboard hidden behind the tiles with a slight overhand onto the drywall?

2. What kind of drywall does the code require? Do I have to use that humidity type drywall or can I use regular drywall for everything else? I read online a little and people say that I should use regular drywall and then proper paint as the paint is what keeps the moisture away. Some people say I should use the humidity drywall on the walls only as it isn't good for the seiling (too heavy). Does anyone know what Calgary code requires?

Thanks

[gram]

In a basement I would only use Dens Sheild: Moisture is your #1 enemy especially in a basement bathroom.


Dens Shield (AKA Dens Guard) which has a moisture barrier and is highly recommended for wet areas such as bathrooms. Typically, it is applied on ceilings as well as walls and can be tiled upon. If painted walls are desired then a skim coat is required. If you use this stuff vs drywall this will be the last time you will ever have to build/reno the bathroom.

The typical bathroom with drywall will need to be redone in anywhere from 5-10 years-spend the extra $1000-$1500 now and never have to do it again.

Also get a really good quality bathroom fan (Panasonic makes nice ones) the more wet dense air you get out of the bathroom the better.

You can literally have Dens Sheield sit in water for years and it will never rot or become mush (will never mold)

Hope that helps,

[broken_legs]

not sure about above mentioned drywall.

I just redid a bathroom upstairs and just about to start boarding the one downstairs. I use Blue Board for the walls, and in the shower stall i used a board called 'Aqua Tough' from Home Depot. It comes in 5 ft sheets which makes doing the 5ft wide shower stall really easy. It's a bitch to score and work with though.

Anyways, i used the aquatough and then on top of that applice this red skin paint on membrane and tiled with normal grout.

Turned out pretty nice.

Remember to get a tub that has a very small lip on it - or notch the studs so the lip is flush. This way the backer board won't sit out on an angle. on the bottom row of tiles.

[garnet]

densshield is the product the correct board for him to use, because it is a tile backer board
the drywall you used is fine for other parts, but it is only just a moisture resistant drywall, not a tile backer



Originally posted by broken_legs
not sure about above mentioned drywall.

I just redid a bathroom upstairs and just about to start boarding the one downstairs. I use Blue Board for the walls, and in the shower stall i used a board called 'Aqua Tough' from Home Depot. It comes in 5 ft sheets which makes doing the 5ft wide shower stall really easy. It's a bitch to score and work with though.

Anyways, i used the aquatough and then on top of that applice this red skin paint on membrane and tiled with normal grout.

Turned out pretty nice.

Remember to get a tub that has a very small lip on it - or notch the studs so the lip is flush. This way the backer board won't sit out on an angle. on the bottom row of tiles.

[barmanjay]

Denshield is good for tile.

Fibreglass reinforced, meant as a cement board replacement, great for the heavier tiles.

I used to install lots of this. People dont know the best way to do the joints/seams, is done the same manner as fibre glassing car body parts. But you use the mesh tape. Also brush the screw holes with the fibreglassing compound. this makes your shower area 100% waterproof.

But for code,.. iirc,.. the green moisture resistant is fine on area that may be exposed to water.

but lets be realistic. you will have your glue,.. tile,.. grout,.. then you seal the grout and then run a bead of silicone along the inside corner (ceiling to tub) and bottom edge where the tile meets the tub.

In theory, if done correctly, no moisture will ever seep past to the drywall.


Blue board is mold resistant and would be a good alternative as well.

When I was taping for builders years ago,.. I had seen just plain drywall in bathrooms on occasion.

[barmanjay]

Originally posted by broken_legs
...
Remember to get a tub that has a very small lip on it - or notch the studs so the lip is flush. This way the backer board won't sit out on an angle. on the bottom row of tiles.


LOL

The lip is supposed to be there,.. you can use it to fasten the tub to the studs.

The drywall is not supposed to go over the lip,.. it stops at the edge of it.

Then the tiles sit lower and flush with the tub. the reason the lip is there, and why you stop the drywall at the edge of the lip is if water does happen to make it past the tile,.. the gypsum wont act like a sponge and soak up the water (believe me it does)

[garnet]

Originally posted by barmanjay
Blue board is mold resistant and would be a good alternative as well.

yes it works, it still absorbs water (being paper) like you say, and it's not a tile backer board specifically, dens isn't much more $, better to use where tiling is to be done, and blueboard the rest


When I was taping for builders years ago,.. I had seen just plain drywall in bathrooms on occasion.

a lot unfortunately, during my contract condo renos, in 4 different buildings here, each less then 6 years old, all had only standard drywall for tub and standup showers, and most all had some degree of mold developing already, as expected really

[C_Dave45]

Originally posted by barmanjay

The lip is supposed to be there,.. you can use it to fasten the tub to the studs.

The drywall is not supposed to go over the lip,.. it stops at the edge of it.

Then the tiles sit lower and flush with the tub. the reason the lip is there, and why you stop the drywall at the edge of the lip is if water does happen to make it past the tile,.. the gypsum wont act like a sponge and soak up the water (believe me it does)

^ Bingo. Don't ever bring the board down over top of this lip.

Couple of points regarding some posts above:

Denseshield is a waterproof membrane in itself. Therefore if its used on an exterior wall, there should be NO vapour barrier behind it...this will void the denseshield warranty.

Concrete board/wonderboard/durock can be used as well...its just a little harder to work with.

Grout is not waterproof. Not even when its sealed. Water will always soak through, but with the proper substrate, not enough to cause any damage.

If you use denseshield, you won't need to use any liquid waterproofing membrane.

To give you one example...the very first tub splash I did was in 1981 for my Dad. I used plain-jaine, regular drywal, and set the tile with thinset. This shower is used at least every day since then...it is still standing. For a normal tub/shower combo, you don't need to go overkill with worry about moisture damage. (Enclosed shower is a different thing).

[djayz]

There's some new stuff on the market that you can supposedly get at Lowes. It's basically the plastic foam but really dense, but it's super light weight and easy to work with and its really strong.

Can't find the link for it but try Lowes for it.

I just re-did my upstairs with the blue drywall, it was a pain to work with because it is drywall after all. Originally I was going to use the cement boards but those things are heavy as shit and getting the drywall up which was probably half the weight was painful enough.

If I were you depending on the price get the foam stuff I talked about above, if its expensive or cant get it just get the blue drywall as it's moisture resistant and costs a few extra dollars over regular drywall.

[broken_legs]

Originally posted by barmanjay



LOL

The lip is supposed to be there,.. you can use it to fasten the tub to the studs.

The drywall is not supposed to go over the lip,.. it stops at the edge of it.

Then the tiles sit lower and flush with the tub. the reason the lip is there, and why you stop the drywall at the edge of the lip is if water does happen to make it past the tile,.. the gypsum wont act like a sponge and soak up the water (believe me it does)

Learn something new every day :)

Believe me I have had to go back and un-do things and re-do them the right way a few times.

Edit: Will NOT be re-doing that tile job :rofl: