Every once in awhile, through sauna building user engagement, I am “wow’ed” with an enhancement to the sauna building methods detailed in my ebook.
User engagement with other sauna builders has allowed me to cross pollinate different ideas and methods. No ego, but with intent to help the next guy down the road. And just as with the Zen and Art of Motorcycle Maintenance, we have the author drawing parallels to understanding the mechanics of his motorcycle as empirical learning towards other aspects of life, I have enjoyed discussing different approaches of the nuances of sauna building with others as crazy as I am.
Because my ebook is in Google doc. format (vs. printed), ever once in awhile we pick up on a better way to do an aspect of the sauna build. And thanks to the non patent process of copy & paste, I am able to share the enhancement with the next sauna builder coming down the pike.
The Ben Square Sleeper Method is a better way to slope a hot room floor.
With my ten or so sauna builds, I have always run 2x stock through my table saw to create sleepers on an angle through my table saw, sloping down to the drain, like so:
A saunatimes exclusive: firing strips to pitch floor to drain. Prep for durarock and skim coat.But let’s check out Ben’s sleeper method:
Welcome Ben:
“Like any other engineer, I can’t help tinkering with a good design. Here is a picture of my floor slope method. I will put reinforcements at the durarock edges as well. Pieces are ripped in 1/8″ increments. Reinforcements for the edges of the durarock will also be added.”
By adjusting our table saw to rip 2x stock in decreasing widths, we create a uniform slope to the drain.
Then cut durarock and mark sleeper locations:
See how an ordained engineer uses a T square to transfer marks onto durarock?:
Transferring sleeper locations with a T square (note mason jar ice water on tile saw so Engineer maintains 38% hydration through process).And an engineer doesn’t need to scratch his head to think about how to mark sleepers for small durarock cuts:
Holding durarock vertical to get sleepers markedNow this is a kick ass sloped floor glued and screwed and ready for the vinyl cement skim coat stage:
A perfectly sloped and supported sauna hot room floor, glued, and screwed and ready for a skim coat water seal (vinyl cement repair: sauna building secret #7).A well built sauna hot room should be such that if kids want to have a hot room water fight, an adult need not have to say “Don’t do that!”
UPDATE: Feburary 2021:
Let’s check in with Mike from High Intensity Health. He has embraced the Ben Square Method, and here he is in action.
24 thoughts on “Slope your hot room floor with the “Ben Square” sleeper method, and enjoy a water fight in your sauna hot room”
Thanks, Glenn!
Just finished putting sleepers in (and filling empty space with concrete). Any tips on
how to seal drain when skim coating? should I pour some of that vinyl repair cement around it
I have it now sitting just like the last video on this page.
Secondly any tips on finding that vinyl repair cement in Canada? Home Depot has it in small 2Gal buckets..
can i use something else (waterproofing repair cement) ?
Thanks, your book has been so great !!
Matt
Hi Matt,
glad my ebook has helped you along. The best way to seal the drain when skim coating is some blue tape laid down tight against the drain cap. Then, after you apply, run a wet sponge to wipe the vinyl cement around your drain. Try not to work it too much or have too much product around there… less is more in that dept.
Vinyl Cement Repair sourcing in Canada: Well, what I would do is google those three words, hit images, and take a screen shot of the blue and yellow bag and circle around with suppliers to get that exact formulation. The 40# bag is all you’ll need to seal off your entire hot room. Run that trowel tight against your cement board (rough side out) as detailed in the book.
And sauna on Matt!
Hi there, I recenlty purchased your book and plan on building a sauna in the spring. Northern Ontario. Im curious to know how the floor holds up over time with the vinyl patch on top of the durarock. Have you ever have it crack with shed movement from frost etc… I am afraid of water seeping under and rotting floor over time. My wife has finnish blood and likes lots of water and steam in hers. The video on the Ben square methode show a black paper under the strips of wood. Does anyone know what this is?
Hi JF:
I’ve had great results with this system. Vinyl patch and durarock work together like peanut butter and jelly. I’ve never had it crack over time, but if it does you can easily repatch. I’ve done that once, just for aesthetics.
Not sure about the black paper, I’ve painted the firing strips just because.
Wishing you good luck, JF!
Hi there,
Thanks so much for this discussion. I was wondering if the sleepers are cut at an angle to facilitate as much contact with the durock? My subfloor is plywood. I’m planning to add some left over roofing peel and stick as a moisture barrier followed by the sleepers/concrete in-fill, the durock and then red guard and tiling. I was concerned about the grout cracking.
Jonathan:
High temp grout may be procured at a fireplace store. You can cut sleepers on angles if you like that.
Hello, I’m about to start my sauna build and thinking about using the Ben Square method. Couple questions: Is treated lumber used for the sleepers? What is the recommended spacing between them? What manufacturer’s drain is pictured? Thank you.
you can use treated, often i’ve used straight pine, and if its a concern, a guy could prime the material with Kills or similar. recommended spacing: less in traffic areas.. you can get a feel by dry fitting your cement board and ensure de sponge ification.
manufactured drain: pushing a cart down the home depot isle will take you to that drain, that’s what i’ve used for a dozen builds.
Do you cut that durarock all the way through? Or just part way so it flexes?
We cut the durarock in sheets, and screw it down to the sleepers. Ideally, the sleepers span just a few inches to avoid flex.
I used the Ben Square method to slope my floor and it worked great! Now that the vinyl patch has dried, there are hairline cracks where the sheets butted up against eachother. Is this something to worry about? If so, how might I fix it?
A friend of mine, put the sloping sleepers on the joists with the subfloor over it, and then the Dura rock directly on the slab floor, which completely eliminated the need for cement between the sleepers. I have a picture of this, but no idea how to send it with This comment
A great idea. I’ve done this also. Many start at the shed stage, with the subfloor already down. good stuff!
Glenn, I did a different variation for the subfloor using a foam cutter to slope XPS down to a drain and then covered that with cement board. Through screwed the cement board down into the joists. Allowed m to insulate the floor without leaving anything exposed for mice to make a mess. Raised my walls to 7’-3” to make up for the lost space. I have pictures to share; if your interested send me an email?
Thanks for sharing this system – ready to put it in my sauna build. One question – why is the cement between sleepers necessary? Just for full support of the cement board over it? Thanks!
Ben:
I’m less of a fan of cement between the sleepers. It may delaminate the plywood underneath over (a long) time.
Check this trick out! It works like a champ! (if you need it).
https://youtube.com/shorts/xue0LuqHqPg?si=XbUFvmbnl1tiXiVA
I am plan I’m going to use the Ben square method. I have a question I have not seen covered. Do I just use the large pieces of durock over the sloping corners of the Ben square. That is, is there enough flexibility in the durock to be tight to the sleepers where the square changes direction 90 degrees. Thanks for your insight
Yes! I prefer Ben Square without filling the space between with cement. There is talk that over time, cement against plywood may delaminate. If you stand on the durock and feel flex.. well.. try this: (and remember that duckboards atop will transfer all the weight): https://www.youtube.com/shorts/xue0LuqHqPg
Hey all – we’re planning to use the Ben Square method in our ~ 8×8’ sauna room with the drain off center under the benches. First question is does anyone have a diagram of the layers of the drain? Or a video on how the drain fits with the durock to prevent leaks so we can properly account for the height of the drain above the ply subfloor?
Is there an ideal slope to the floor? 30:1?
hmmm.. I never thought about what that slope would be. 30:1 seems good. Just enough that water knows where to go, and duck boards atop, and you’re there!
Hi Glenn,
Can I use NobleSeal TS Thin-Set Waterproofing Membrane that provides waterproofing and crack isolation on top of slope mortar avoiding the durock installation? Also if not using waterproofing membrane with durock – vinyl cement skim coat does not provide waterproof. What do you recommend to install on top of durock with skim coat – porcelain tiles? I have some Waterproof Luxury Vinyl Plank Flooring left overs from kitchen remodeling – can I use those?
Thank you.
This is a very helpful guide. I’ll be using this in my build later this month.
Sorry for the late comment, but I have two questions:
1. Are the cement pavers placed on the subfloor to avoid having the stove/stone weight sitting on the finished surface to so as to prevent cracking or damaging it?
2. What do you do between the pavers and the topmost surface (tiles etc.), do you caulk this or run grout between the pavers and tiles?
He Justin!
1. Yes, stone pavers on the subfloor as a good solid base for your stove.
2. I’ve put construction adhesive under and between the pavers, but for a couple of builds now, I’ve skipped that step, just butted them tight, then locked them in with the Ben Square material. Vinyl cement skim coat over everything.