Glad you found it helpful Mr. Random-person-that-I-completely-do-not-know. 😏 I find that installing concrete board and waterproofing it (if needed) is a fairly straightforward process. However the curb and actual pan mud is a little more difficult. I'm not the best at that part so I'd suggest looking up someone who forms a curb with lathe and mortar. Don't do it the easy way which is to install with concrete board and screws. Even if you waterproof over it you will still have moisture that makes it through and will eventually cause water damage.

It never hurts to follow the mfg. instructions, but honestly, I don't push a pre-slope because the way concrete/mortar absorbs water, I've never taken apart a shower that was dry or didn't have moisture trapped in the mud bed, slope or not. I have wondered about showers with radiant heat and I would think they would dry out better, but I haven't noticed a difference in traditional pan showers with a pre-slope. I have seen terrible waterproofing jobs though that have led to all kinds of issues and I highly distrust Kerdi and similar systems which rely on a top coat or thin layer to prevent water damage. I've only demoed about a dozen tile floor shower though (most tile shower stalls around here are installed over an acrylic base), so it's far from a huge body of evidence.

Pure slope mandatory in a mud and liner shower. It’s a water in and water out system. No pre slope and wood curbs are problem in the industry.

Your correct pre slope is critical

So maybe I only touched on it briefly but I form lathe and put it over the curb and then use fast setting mud to form the curb after I do the dry pack. The dry packmud holds the lathe in place and the two bond together well. It's a simple process really. No screws through the liner and no issues with leaks. As to the pre-slope. I have torn out a lot of showers, with and without pre-slope and I have never seen a difference unless there were other funky things going on. It's always nasty under the concrete and there's always moisture, but it doesn't matter because it's all under the tile. I'd be curious to know if you've seen different because a pre-slope to me makes zero since from experience and also from logic since most people take a shower every day and the concrete is like a sponge so that water doesn't flow like in an open space. The concrete never dries out either way. So, if there is something I'm missing I'd be glad to hear it.

@@MyFortressConstruction the industry has gone way from using lathe in curbs. Because it rots and rusts. In my experience a wood curb failure rate is very high.

@@MyFortressConstruction the water goes through your deck mud onto the liner. Those showers are known as water in and water out. The water does go through the mud. If it’s flat no pre slope. The mud becomes saturated and without the slope under the liner the water has no where to go. It begins saturating the pan and after a while you’ve built a small swimming pool to hold all that water. You need a pre slope and you need to protect the weep holes at the drain so that the water can fillet back down the drain. As you said it’s pretty simple. I’ve worked in large cities like Seattle and at the water test of the liner. The inspector won’t check it off until he sees the water drain on the pre slope. Pre slope isn’t something just made up it’s there for a reason.

@@Apexjasonmorganllc You can't go wrong with doing a pre-slope. My flawed argument is simply that in all of the old showers I've taken out I haven't seen an issue even thought they didn't have pre-slope. But it only takes one bad job so, yes, do a pre-slope.

So it really depends on what is available. A pre-mixed version is usually available from Quikrete, or Sakrete and it's called "Sand Mix", or "Topping and Bedding Mud", or "Sand Topping Mix", or "Deck Mud". But if you can't find anything like that then you can mix it up by getting regular old sand and portland cement and mixing it to a 4-1 or 5-1 ratio. So if you have a 3x5 shower and you're estimating an average of 2" thick base then you'd have 2.5 cu. ft. of volume needed and each 50 lb bag of sand is about .5 cu ft so you'd need four bags of sand and a partial bag of portland cement (not a mix, it has to be straight portland cement). So, for something like that I'd just buy a pre-mixed deck mud because I won't need a whole bag of portland cement (they're usually sold in 94 lbs/3cu ft bags).

I don't suppose I understand what you mean exactly, but on a corner like that (there are actually three of those same corners in this shower), you have to fold the oatey corner dam back. It is super flexible and doesn't pose any risk of it pulling apart later. If you meant something else feel free to clarify and I'll try to answer again.

Yes, so after the pan is done the inspector comes and then it's ready for the tile guy who will do the mud bed and tile work. Most tile guys won't tile on top of someone else's mud bed, or at least won't guarantee the work.

Yeah, so there are a couple of reasons why we didn't do one here. One being that getting someone to do a curbless properly is nigh impossible. Even a simple pan liner proved to be difficult. The other being cost. It seems like the construction industry is full of people that can do a job so it looks correct, but don't understand the unseen engineering that goes into the prep. It's why there is so much water damage inside people's homes. I feel like I have to teach something new to every sub that does a job, whether they've been doing the work for 2 years or 20.