The following five-part series gives a basic overview of building a shower floor for tile. If you would like a complete step-by-step of the entire process with all the little idiosyncrasies and details  I now have manuals describing the complete process for you from bare wall studs all the way up to a completely waterproof shower substrate for your tile.

If you are tiling your walls and floor you can find that one here: Waterproof shower floor and wall manual.

If you have a tub or pre-formed shower base and are only tiling the walls you can find that one here: Waterproof shower walls manual.

Curb and Pre-slope

Image of a shower diagram

Properly built shower

There are a couple of options to create a shower floor for tile using deck mud. The first is a single-layer shower floor which can then be coated with RedGard or a similar product or covered with kerdi to waterproof it. The other is a normal shower floor with a liner which will have two layers – a preslope, the liner, then the top slope which is then tiled. This series of posts will describe the latter.

Before we start I should note that unless you are using the kerdi waterproofing method or utilizing a liquid membrane as your floor liner you should not have the backerboard installed in the bottom part of the shower. Your waterproof membrane for a shower floor will be installed behind your backerboard. The curb and pre-slope need to be completed before installing the lower wall substrate.

Creating the curb for a wooden floor

The first thing you must do is create the outside curb of your shower. You need to create the “box” which will become the inside of your shower floor. Depending upon whether your shower will be created on a wood or  concrete floor will dictate what material you use for your curb.

If you have a wooden floor you want to use regular dimensional lumber. The 2 x 4’s they carry at Home Depot – those. That is the easiest and most readily available material. Ideally you want to use kiln-dried lumber. That is lumber that is, well, dried in a kiln. By removing moisture in this manner the moisture content of KD lumber is normally between six and eight percent compared to regular dimensional lumber at close to 15%.  Why does that matter? Well moisture and wood don’t mix. As it dries wood has a tendency to warp and twist. The less moisture initially in the wood the better.  KD lumber is best and regular air-dried dimensional lumber is also acceptable. NEVER use pressure treated lumber – ever.

I usually use  three or more stacked 2 x 4’s to create my curb depending on the size of the shower. Simply screw the first one to the floor (with correct non-corrosive screws), stack the next one on top and screw it down, and so on until the desired height is reached. That easy.

Creating the curb for a concrete floor

Image of a brick curb

Using Bricks for a shower cub

For a concrete floor you want to use bricks. Yeah, bricks. Just stack ’em. I use gray concrete bricks (no holes) and stack them two or three high for my curbs. You can use just regular thinset to adhere them to the floor and to each other. Just stack them in the shape you want.

You do not want to use wood for your curb on concrete. Wood will actually absorb moisture from your concrete and start to swell.

Creating the pre-slope

This is one of the steps most often skipped by a lot of people – amateurs as well as professionals. It is imperative! You need it – it’s that simple. Without a pre-slope your waterproof liner will lay flat on the floor. This does not give water anywhere to go. It will sit there, stagnate, mold, . . . you get the idea. With a proper pre-slope any water will drain to the weep holes in the drain and go where it needs to – away.

Lathe for wooden floor

Lathe installation for wood floor

You need to first make sure your shower floor will stay where you put it. On wood you can use regular metal lathe.

You need to place what is called a ‘cleavage’ membrane beneath your lathe. This is just a sheet of plastic or tar paper stapled to your wood floor first with the lathe placed over it. The membrane does not make anything waterproof! If someone tells you that hit ’em in the head with a bat. It is necessary to prevent the wooden floor from sucking the moisture out of the pre-slope prematurely causing it to cure too fast (or not fully) and significantly weakening it.

When your membrane is down staple the lathe over the top of that. Just cut it to the shape of your shower floor and lay it flat on the floor and staple or nail it down. This gives your mud bed something to grab onto. In the above photo I have used plastic as my membrane and only have a partial piece of lathe in – make sure you cover the entire area below your pre-slope.

Image of a properly prepared pre-slope

A properly prepared pre-slope

For a concrete floor you need to mix up some regular thinset except you need to mix it “loose”. That just means you need to add a bit more water than the instructions call for to make it thinner. Cover your shower floor area with this before you start installing your deck mud. The deck mud itself does not “stick” to anything, you need to supply something that will adhere it to your substrate.

Oh crap – Math???

To make the installation easier you’ll want to mark your height lines on your wall studs. To figure out how high it needs to be off the floor you need to figure out your slope. This involves a bit of math – don’t panic! It’s easy. Figure out which corner is farthest from the center of your drain. Your slope needs to go up in height 1/4″ for every foot. If your furthest corner is three feet from your drain center your slope needs to rise 3/4″. Easy enough so far, right?

Your finished floor (after your liner and top mud bed are installed) needs to be 1″ to 1 1/4″ thick at the drain. So, if we make the pre-slope  3/4″ thick at the drain it needs to be a total of 1 1/2 inch thick at all your walls. So mark a line 1 1/2″ from the floor all the way around the wall studs. This will be the height of your pre-slope at the walls. I try to make my pre-slope the correct thickness at the drain so it will be 1 1/2″ at the walls. This way you do not need to draw lines, just level your perimeter with the top of the 2 x 4 studs along the bottom of the wall. Depending on the size of the shower it doesn’t always work, but it saves time if you can work it out that way.

If your shower is not a square, and they rarely are, you still need to have the same thickness at the walls all the way around the perimeter. This means that you will have a steeper slope on the walls closer to the drain. This is normal. If you don’t do it this way you will have uneven tile cuts at the bottom of your wall. By doing it this way you will ensure a level line and, in turn, a level floor around your perimeter.

The height of your pre-slope at the drain can vary. It  needs to be level with the top of the bottom flange of your drain. Regular drains have two flanges which bolt to each other. The pre-slope needs to be at least level or a touch higher than the bottom flange. Your liner then goes between the top and bottom flange to utilize the weep holes in the drain. This allows any water atop the liner to drain. The pre-slope supports the liner so it needs to be level or above every point of the lower flange. Does that make sense?

This is why planning is so important. Your drain needs to be high (or low) enough and your curb needs to be higher than your shower floor – naturally. So figure all this out before you build anything.

Playing with mud

Now we need to mix up a batch of deck mud. Check out that link, I’ll wait . . .

Okay, once your mud is mixed up you want to start packing it in there. If you are going over concrete and have your thinset slurry down, cover the entire bottom of the shower floor first to ensure the entire base will stick. If you have a large shower only spread as much thinset as you can reach over at a time. Start at the walls and pack your mud down really well – beat the hell out of it. Seriously, beat it like the last DMV employee you spoke with. You want to eliminate any voids and create as dense a bed as possible. Don’t worry, it won’t hit back.

Pack it down around the perimeter to just above your line. When you get that done get yourself a 2 x 4 about 18 – 24 inches long. Lay that on top of your mud bed against your wall and tap the 2 x 4 down with your hammer until it is even with your line. This ensures a level, even line all the way around your perimeter. Perfect! Now don’t touch the edges.

Image of properly prepared deck mud

Properly prepared deck mud

Continue to pack mud into your shower base all the way from the perimeter down to the drain. You should have a straight line from the perimeter to the drain without any dips or humps. This will allow water to drain correctly without pooling anywhere. While this particular layer of your shower floor does not have to be exact, you do need to make certain it is fairly flat in regards to the line from the perimeter to the drain.

Image of a consistent pre-slope

Ensure a consistent slope

That’s it. When you get it all packed in there it should have a shape similar to a very, very shallow bowl. Now leave it alone. Really, leave it alone. The next day it will be ready to install your liner and all that fun stuff. Don’t play with it until then.

In my next post I will show you how to install your waterproof liner. Until then leave your pre-slope alone. It’s fine. Quit trying to perfect it. We’ll do that tomorrow. Get away from it. Really. Stop staring at it . . .

Read this next if I haven’t already bored you to death: How to create a shower floor Part 2

{ 748 comments… add one }

Leave a Comment

  • Ben

    Hello Roger.

    Thanks for all the info you post, it’s is awesome and super helpful! I have a question regarding the curb on concrete slab. I’m fine to use bricks for the curb, but what about the shower stall framing, and more specifically, the framing of the knee walls and bottom plates of those walls and the house framed walls? Those are already installed and are regular KD studs?

    Could you advise your thoughts on that and won’t those be susceptible to absorbing the moisture from the concrete as well? the slab is about 35 years old if that is relevant.

    Have attached a pic for reference and note the 1 curb stud I plan to swap after reading your post here.

    Many thanks for any advice here.


    • Roger

      Hi Ben,

      At the very minimum your footer studs for your walls should be PT lumber. Yes, kd will absolutely absorb moisture, and in most places it is prohibited by code to have kd lumber against concrete. The regular wall studs can be kd, but the footers have to be pt.

      • Ben

        Thanks Roger. So the question now is, is it the end of the world if I don’t rebuild those knee walls with pt lumber as footers?

        • Ben

          And adding to my end of the world question, you mention “NEVER” use PT lumber under the curb built on wood sub floor, and curious as to why never here, but always on concrete. And referring here only to my knee walls and their contact with the slab.

          • Roger

            If you build a curb with PT lumber there is NOWHERE for any swelling to go – at all. It is surrounded on all sides with tile. And there is no moisture absorption from the concrete (over wood) to stabilize pt lumber. It will dry out, begin to shrink and twist, which leads to excessive movement in your curb – which is surrounded on all sides by tile. Something’s gotta give – it’ll be the tile, every time. PT lumber on concrete will not shrink because is continually absorbs moisture from the concrete – it’s stable. KD lumber on concrete does the same thing – but the moisture will cause it to expand.

            • Ben

              Hello Roger.

              So waging on annoying you, I am a little bit confused. My first question: So it is ok to have the PT wood on top of the slab as base plate for the knee walls and regular KD lumber as rest of framing for knee walls?

              And by this below, you meant PT wood on a wood subfloor?:
              “If you build a curb with PT lumber there is NOWHERE for any swelling to go – at all. It is surrounded on all sides with tile. And there is no moisture absorption from the concrete (over wood) to stabilize pt lumber. It will dry out, begin to shrink and twist, which leads to excessive movement in your curb – which is surrounded on all sides by tile.”

              and I got confused because then you said this: “PT lumber on concrete will not shrink because is continually absorbs moisture from the concrete”

              Thanks for humoring me!

              • Roger

                Hi Ben,

                Yes, pt for the base and regular kd for the rest is fine. The kd never has direct contact with the concrete. And yes, I meant on a wooden subfloor. Sorry for the confusion but if I didn’t put that I would have 300 questions in the next few days about using pt over wood. :D

                • Ben

                  Roger, many thanks for your insight! Really appreciate it.


        • Roger

          It’s not the end of the world, but you may very well run into problems down the line when those footers absorb moisture from the concrete and begin to swell.

  • Marisa ward

    I purchased the ebook yesterday but haven’t received the email link for the book.

    • Roger

      Hi Marisa,

      Not sure what happened, but I’ve just reactivated your link and resent the email. If you don’t see it check your spam folder.

  • Chris

    Hi Roger.

    Thanks for all of your very helpful stuff here! I have been struggling with my pre slope and have had to rip it out twice. Then I realized that the subfloor was not level by 1/4” per foot sloping away from the center drain. If I were to do my preslope at 1/2” per foot, wouldn’t that make up the difference and equal out at 1/4” per foot? I’m just trying not to have to rip out the framing and the drain if I can help it.

    • Roger

      Hi Chris,

      Find the spot that 1/4″/foot ends up the wall (the highest part of the subfloor). Then take the entire deck up to that level. It sounds as if you are measuring your slope off of the subfloor itself and trying to have a consistent thickness all the way around. It doesn’t matter if it’s 2″ thick at one end and 4″ thick at the other, it is the slope itself you need to be concerned with, not the thickness of the deck at any given point along an unlevel subfloor. Just make sure the perimeter of your preslope is level.

  • Paul

    Hello Roger,
    I believe i’m ok from reading prior posts but wanted to double check before starting my pre-slope…

    My rectangular’ish shower wooden subfloor slopes a bit and the top of my lower drain flange is only 1/4″ off the subfloor. Using the 1/4″ rise per 1′ formula my level line around the perimeter of the shower at the high corner is only 5/8″ deep (just over 1 1/2″ deep at the opposite corner). Do I need to take any additional strengthening steps outside of lath, roofing paper and a properly mixed deck mud to ensure this relatively shallow pre-slope will be stable?

    Hope this makes sense. Thanks for the clarification and the manuals!


    • Roger

      Hi Paul,

      Nope, that will be just fine.

  • Steven

    Can’t thank you enough for how helpful your site has been!

    One thing I could not find though is how to do a curbless shower on a basement concrete slab. I have already cut a 38″ x 38″ area from the concrete all the way through to the dirt. Now I am at a standstill. I am not sure how far I should dig in order to lay a solid base.

    The 38 x 38 slab that I cut out was 3.5″. I was thinking I should dig down another 3″ beyond the 3″ it took to get through the concrete. This would enable me to pour a 3″ slab to support the pan liner and give me 3″ for a mortar bed to lay the tile on.

    Do you have a blog on this particular situation? If not, does this sound like the best way to do this?

    • Roger

      Hi Steven,

      I have not yet written anything on curbless showers (it’s on the list). Yes, that sounds like a perfectly acceptable method.

      • STEVEN

        Thanks for the reply. Seems to be limited info on curbless showers in relation to installation on a concrete slab.

        Most were saying to use a combination of a concrete saw to make lines than a chipping tool to remove the concrete. Logic tells me that would not be a good idea when dealing with a 3-5 ” slab.

        Any suggestions on things I might want to consider or keep in mind when doing this? Though I have done a lot of research, this will be my first shower so any info or tips are greatly appreciated!

        • Roger

          Oh, it sounded like you’ve already removed the concrete. Go buy or rent a bosch bulldog (it’s a rotary hammer). It will bust up that concrete fairly quickly.

          • Steven

            Funny I was just reading this blog again when you replied.

            I’m sorry, after I read what I wrote I realized it sounded as if I hadn’t broken through the concrete. It should have read “Logic told me that would not be a good idea”. I attached an image of what has been done so far.

            Anyway, after re-reading this blog, I am wondering if I would be better off going with just a topical liquid membrane like hydro ban.

            I had considered this in the beginning but was talked out of it by a handful of people that proposed to either do it the old way ( pre-slope with pvc liner) or a combination of both.

            If you could just answer me this last question. Provided I follow the directions of the hydo ban, is there any reason I should worry about this product being used as a topical membrane alone without the help of any other water proof methods??

            • Steven

              Looks like the image did not upload. Lets give this one more shot..

            • Roger

              Hi Steven,

              Absolutely not. Hydroban IS a waterproofing membrane, and is often used (by myself included) as the only membrane in a shower. Whoever talked you out of that needs to stop giving advice on waterproofing.

              • Steven

                I’m assuming Hydro ban works over hardiebacker board as that’s what I purchased.

                I know I said last question but I really can not find an answer to the exact steps to fill the 38 x 38 area that I cut out from the concrete slab.

                Again, I’m assuming that there is more involved than just pouring regular concrete in the hole.

                • Roger

                  Yes, hydroban works over hardi. You want to fill in the bottom of the open area with gravel if it is below the bottom of the slab. You want it AT LEAST up to the bottom of the slab. Then just mix up deck mud and fill the rest in with the proper slope just like any other shower floor (except you’ll have a single plane slope because of the linear drain).

                  • Steven

                    Thank you!

                  • Steven

                    Hello again.

                    I plan on moving forward with this over the weekend. Again, peoples opinions have delayed my moving forward.

                    I have been told that I should dig 3-4″ lower than the bottom of the current slab to re- pour a new, lower slab for my sloped deck mud to sit on.

                    You suggested just filling the area AT LEAST up to the bottom of the slab. Then just mix up deck mud and fill the rest in with the proper slope.

                    All this whispering in my ears has me a bit nervous! Is there anything I can or should do to better prepare the ground/dirt as a better more stable subfloor? Or would I be better off doing as they have suggested and pour a lower slab as a subfloor??

                    • Steven


                      You suggested just filling the area “WITH GRAVEL” AT LEAST up to the bottom of the slab. Then just mix up deck mud and fill the rest in with the proper slope.

                    • Roger

                      Hi Steven,

                      Correct, just gravel up to the bottom and then deck mud.

                  • Steven

                    Hey Roger! I finally put in the mud bed. I ended up using quickrete 3:1 straight from the bag because I was afraid I’d mix wrong and my logic told me the higher cement ratio may help for my situation. I did have trouble getting the top completely smooth though. I didn’t want to keep messing with it though so I decided to leave it alone.

                    Looking at it after, there may be a couple high spots. Is this something i should worry about? What is the best way to deal with this? I literally just finished up and hour ago so if there is something I should do before it dries all the way I can still do that. Otherwise, I can wait until it completely dries. Not really sure how long that takes.

                    • Roger

                      Hi Steven,

                      You want to get rid of the high spots. You can sand them down. Use a brick. Really. A regular brick will sand the high spots down.

  • Jesse

    Here’s a picture. I don’t think it uploaded earlier

  • Jesse

    I bought your topical membrane manual which is helpful. I’m doing a stand alone shower on a slab. The slab has a couple of cracks running under the shower. No vertical displacement, biggest one less than 1/8″. The crack will run right under the curb. Should I put an isolation membrane down before I put in the curb and mud bed and build the shower on that? I’m afraid its going to crack over time. Also as a bonus, the water lines are proud of the bottom plate. I plan on putting a relief in a 2×6 and making a faux curb on the walls rather than move the wall out. any thoughts on that?

    • Roger

      Hi Jesse,

      Yes, you need some type of separation between the floor (crack) and the curb. The deck mud will handle everything under the shower, so that isn’t an issue. I would move the water lines, but that’s me, and I know it’s a pain in the ass. If the faux curb thing works for you it’ll be fine.

  • Ray

    Also after redguard on my floor dries should i water test it

  • Ray

    I cant find the stucco base to use for my curb local. Can i use type N mortar that is premixed and all i have to do is add water. Thanks again for your input.

  • Ray

    Another question do i build my curb first or attach the cement board first i know i out board on before i do the bed but was wondering if i do curb before or after i install wall. Thanks

  • John

    I put my preslope in and it looks great. When I pulled the tape off my drain fitting I found the drain fitting off level by 1/4″. It is a square top type 3 piece. Any way to tile it so it looks OK? Or do I need to dig some of the mud around the drain fitting and try to level. May be complicated by fact I cut out subfloor 4.5″ and sealed around fitting with spray foam.

    • John

      So looking again, with the top screwed out to 1 1/4″ I can move it side to side enough to get it level to half bubble off. About like me I guess and close enough for me. Can I block one side while packing top mud and get it close? Then remove block and finish?

  • Ray

    Hey again
    Again i am using brick for my curb i assume i still use lathe to hold the liner to it do i do this before i do preslope before final mud bed or after final mud bed and then do i pack it in with deck mud all over even on inside down to bed ans smooth it out then tile

    • Ray

      Also i have heard of people only doing one mud bed the painting it with redguard. Is this a good way to do it? If so would i just do a thicker bed and put lathe over curb before i do bed then pack with mud smooth it and paint it with redguard?

      • Roger

        A topical waterproofing is a better option (redgard). You would just do the single slope with the lath over the curb first, mud the curb as well, then paint it all with redgard.

    • Roger

      Hi Ray,

      Yes, you still use lath over the liner (over the curb) before you install the final mud bed. Then you pack it down with wet mud (just deck mud with powdered lime added to it). You can do it with deck mud, but it’s just not sticky, so it’s difficult to use on the sides. It will work, though.

  • Ray

    Hey roger
    Great site. My shower will be 32″ wide by 60″ long. There used to be a corner shower there. My drain is about 16″ from long wall and about 9″ from short wall(the wall with shower fixture) you said its best to have preslope same thickness all way around perimeter. Would that be too steep of a slope around drain or no? Also how do i get the slope on curb made from the gray brick? And i am gonna have to put in the drain does the bottom of the flange need to be sitting on the concrete floor,slightly above floor or slightly below. Thanks.

    • Roger

      Hi Ray,

      I prefer a non-level slope around the perimeter in that case. You just need to cut the bottom row of tile to fit it. It looks much better than a slope that large at one end of the shower. When you install the bricks just put a little more thinset under the outside of the shower than the inside under the bricks. The bottom of the flange should be about 3/8″ above the slab.

  • Ray Burrill

    Hey Roger, i just finished my concrete shower basin per your direction and wisdom from your e-book. And it turned out well! Regarding attaching backer board to the walls, i read in your tips that i could have put the stuff on first, then made the floor, thus securing the bottom nicely in the base. But, i did not. so…. my question is… with my liner coming up the wall almost a foot, how do i properly secure my backer board along the floor? Can i trim it down to 5 or 6 inches and screw down to that point, leaving the remainder just hanging there? Thanks in advance for any input you may have……….Ray

    • Roger

      Hi Ray,

      You can screw all the way down to three inches above the curb. Everything below that just hangs there.

      • Ray

        And I thank you sir!

  • Andrew W

    First off, just want to say thank you. Your website is really helpful. I finished ripping out my 90s fiberglass shower surround and base, and found my drain looked like this (see attached picture). I guess the shower was added after the House was built and they jackhammered and tied into the plumbing and just left loose gravel supporting the drain. I’m guessing this is not the best way to do this…How would you fix this for before making the shower pan? Pour concrete to fill It in or something else? Can I leave the wood in there or take it out? Thanks

    • Roger

      Hi Andrew,

      You can fill it with concrete if you want to, or you can just pack it with deck mud as you make the pan. The wood can stay, it won’t hurt anything.

  • Mike Gerber

    Made a slight goof and need to add more deck mud to level out the floor at the wall side. You mention that you can add more mud but need to put down thinset first. Silly question…let the thinset dry before adding more mud?

    • Roger

      Hi Mike,

      Nope, put it on the wet thinset.

      • Mike Gerber

        Crap. I let it it dry. Still ok?

        • Roger

          Sure, as long as you put more wet thinset over the dried thinset. :D You need to bond the deck mud, that needs to be done with wet thinset – just like setting tile.

          • Mike Gerber

            Well I messed this up from the beginning. Didn’t see your reply in time. Went ahead and put the new mud over the dry thinset. Looked ok. Now I’ve gone ahead and applied the red guard over the top. Should I try to pull it all up? I only put mud on about 1/3 of the pan where it was dipping a bit.

            • Roger

              Nah, leave it. It’ll likely be just fine.

  • Aaron

    Hi Roger
    I’m making a shower pan on a concrete sub floor. How do I adhere the Pre slope?How do I attatch the liner to the outside of the curb? Also how Do I mud the outside of the curb with the liner, lath over the liner? Thx

    • Roger

      Hi Aaron,

      Thinset over the slab and the mud over it bonds the deck to the concrete. Bending the metal lath over the cur holds the liner to both the inside and outside, then you mud over the lath to create your curb – inside and out.

  • Lee Clayton

    Hi all, I was reading your posts with interest and wondered whether a pre cast former manufactures from plastic and could be cut to suit the size of the shower and could then be tiled or vinyls. I would be happy to forward a picture of the product in question. Regards lee,

    • Roger

      Hi Lee,

      Not quite understanding if this is a question or you’re trying to sell a product. If you are asking about bonding tile to plastic of some sort – it won’t work in a shower base application.

  • Patrick

    Hi Rodger, I’ve got my shower pan in Pre sloped liner deck and I’ve tile that with some mosaics all the way to the liner now I was going to put the walls on I was going to use drywall a moisture barrier and then HardieBacker and those will be in front of the liner is that sound accurate and should I caulk the space Where I Leave the CBU above the pan floor my cock I mean 100% silicone. Thanks

    • Roger

      Hi Patrick,

      All except for the drywall. Why are you putting drywall behind your backer and barrier? The backer and barrier should be attached directly to the studs.

  • Trudy

    How do I put a drain in when the floor is finished tile and the water drain for the washer is on the other side of wall about 8-10 feet away on opposite side of wall.

    • Roger

      Hi Trudy,

      You call a plumber. :D At least some of the tile will need to be removed and replaced, you can’t install a drain without doing that.

  • Christine

    Hi Roger: I’m thinking of using bricks on my concrete slab to build a shower curb. I’m wondering how to create some pre-slope on the curb itself. Wooden shims?
    I’m planning to use Kerdi-board over it to water-proof it before tiling.
    Thanks! Christine.

    • Roger

      Hi Christine,

      You don’t want any wood in there at all. Since you’re using kerdi-board just use a bit more thinset on the outside of the curb than the inside on the top piece to create a slight slope. Or you can just do it normally by doing the same thing on the bricks themselves as you install them.

  • Lee

    Hey Roger,
    Great site, I’m glad I stumbled on it!
    I’m building a custom shower in my home about 36″x33″ that will sit on a subfloor that has overfloor radiant pex installed on it. For the walls I was planning on doing hardi and red guard rather than a moisture barrier behind the hardi. For the shower floor I am doing your blog method as opposed to kerdi hoping to capture the radiant heat in the thermal mass of the concrete. Any special considerations with radiant I should be aware of or things I may want to do differently than in your blog?

    • Roger

      Hi Lee,

      Not really, just don’t screw anything through it. :D If you use a topical method for your floor it’s actually more heat-inductive. You’ll only have one slope rather than two, so half the thickness of mud for the heat to get through.

      • Milton perez

        Thinset, mud slope, and redguard to a one piece drain glued to 2″ drain pipe Ok? Then Thinset and tile.

        • Roger

          Hi Milton,