🤔Before you install tile find out if the floor is strong enough? What you need to know.

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Floor deflection must be known before you install your brand new Porcelain tile. If you have a plywood subfloor, and you want to install a ceramic tile on that floor, then you have to find out if it is strong enough, or stiff enough to support you new porcelain or ceramic tile. The minimum deflection for a ceramic tile floor is L360. If your floor does not meet the required deflection amount, the floor tiles can crack, come loose, you can have failing grout and in all likelihood, the tile floor will fail and need to be replaced in short order. In this video I describe how to determine if your floor is capable of supporting a ceramic tile, and the app I use to calculate the deflection of any floor by measuring the dimensions of the floor joists, the spacing and unsupported span of the joists. It is critical to know if the floor is sufficiently stiff to support a tile floor, this step should not be skipped and if the floor fails to meet the deflection minimum of L/360, measures can be taken to strengthen the floor structure to make it strong enough for porcelain tile.
All tile installed by Sal DiBlasi, Elite-tile Company, in the Boston North Shore area. This video contains affiliate links, which means I will receive a small commission if you click on the product link.
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[@losll]

Great info. My upstairs is bouncy. First I thought it was the plywood not being thick enough. Now I’m thinking it’s the joists. Keep up the good work!

[@markguagenti9342]

Amazing Sal, thank you for the education! Priceless information. Happy Holidays Sir

[@elisabompadre8]

Thank you so much!!! So glad I watched this before doing my slate instal

[@coreylawler4034]

Great video! I wish more tile guys knew this

[@sd0427]

Thanks Mr Diblasi. Excellent.

[@janealway6566]

THANKS great video - im astounded at what was NOT taught at uni.

[@deborahwoodbridge8145]

Wonderful info Sal!!! Thank you so much!!!

[@justinhc123]

Great to keep in mind. Thank you!

[@DC-cb4mv]

Marry Christmas Sir! Lots of love from Edinburgh !

[@SalDiBlasi]

Thanks, Merry Christmas to you as well🎄👍

[@Handyguy223]

Nice! Using the Tile Geeks app. I have it also, I am now a fellow geek. Great video Sal and thanks for all your hard work on these, they benefit many.

[@SalDiBlasi]

Tile Geeks, great group of people, you should look into GTP as well. See you on FB

[@adamr1637]

Sal, Great videos! Would love a video on things to know for natural stone installs! Thanks for sharing your expertise!

[@joer825]

He does address it. Porcelain tile is L/360, natural stone is L/720

[@MC-lj2jg]

Thank you Sal!

[@MrLutzyboy]

Sal, These are the topics that makes you a TOP Tile Professor in my eyes. In my kitchen the builder graciously gave me an I-Beam structure made of engineered plywood. The builder also gave me I-Beams that are 24inches on center for the entire span of the kitchen. There is also about a 27ft of span as well. Too late to add lollies, finished basement. I was able to sister 1inch thick plywood to each beam on either side, glued and screwed for a good 15ft of span. I will add another layer of 1 inch real plywood to the floor. A thicker floor will have less deflection. I wish there was a way of measuring deflection without calling in an Engineering company to do it.

[@SalDiBlasi]

You can determine with the deflection with the app, however the deflection should be designed into the floor when the house is built or remodeled to mee the deflection of the intended purpose and material type of the floor. This is not the job of the tile setter, but something he should be aware of. Sometimes wanting a thing and being able to have it are not possible.

[@kartFerrari]

Thank you. Learned something new and useful.

[@SalDiBlasi]

Glad it was helpful!

[@Lu-cho]

Also found this video helpful thanks! 😱 more work! A granite/tile business is retiring and he is selling everything a cheap price. My friend purchased a travertine les that $1 so now he have few pallets of travertine... i thought he only need the ditra! Maybe vinyl flooring is faster! Thanks for your help.

[@bluesdirt5889]

Great video !!!

[@user-dk4le1ds1z]

Thx, great info.

[@AnthonyLeeBand]

Happy Holidays Sal!!

[@SalDiBlasi]

Same to you.

[@55098]

Very informative video

[@eltonnoway7864]

The "app" Sal links to is great, especially if you're a contractor in the field going from job to job because you'll always have it with you on your phone. However if you are a DIY'er at home doing your own kitchen or bathroom and you only need to do a one time calculation there are several good "free" PC and Mac based apps online example: The John Bridge Deflect-O-Lator

[@joer825]

Great video Sal. I believe that TCNA (Tile Council of North America) has introduced another important guideline - deflection for large format ceramic tile (Large format tile is considered any more than 15" long in any direction) is L/480. So normal tile L/360, LFT L/480 and stone L/720. I think they introduced that in 2019 or 2020, after this vid came out.

[@SalDiBlasi]

The language for deflection standards has changed in the 2020 handbook, but there is no mention of L/480. The change has to do with the assignment of responsibility for determining if the deflection. It makes clear that it is the responsibility of the builder or the homeowner, or design professional to make sure that proper deflection was designed into the floor assembly.

[@gilzr473]

Great video, thanks for sharing 👍👍

[@SalDiBlasi]

Thanks for watching

[@LandbergTileTV]

Very cool app, thanks for sharing this piece of information! 👊

[@SalDiBlasi]

Lots of useful stuff in it.

[@ralphtulio3916]

Can you tell me the name of the app? Thanks.

[@lisabrown6691]

@@ralphtulio3916 Tile Geeks

[@WarmMyHeart]

Learn something new everyday! Hey sal hope you are well my friend.

[@SalDiBlasi]

😊👍

[@cathiefirestone5374]

Hi Sal, we got 20" tall Advanced mechanical trusses, 3/4" tongue and groove CDX glued and ring shank nailed...the tile geek app says we should be good with porcelain planks...24' truss length...wish they had more joist/truss selection in the app. Great videos...keep em comin

[@SalDiBlasi]

😊👍

[@sujantowongso4586]

Sal, thanks for the video. Our subfloor is currently based on 10x5 (hxw) cm of joist with a gap between each joist at 40cm. The previous owner of our house had laid a ceramic tile over the wooden floor above the joists. I am not an engineer, but just wonder if the floor will still be strong enough if we are to lay another wooden floor above the existing tile. I am thinking of not ripping our the existing tiles. Thanks in advance for your reply. Regards.

[@apexhomeimprovementsllc2489]

another great video. Question is I tore up a 2-year-old sheet vinyl floor and the adhesive is still on the subfloor. Do I need to remove the adhesive completely or just until its smooth? I'm worried if its water soluble that the thinset wont adhere to the floor. I'm using Ditra for my underlayment. Thanks Sal ! Love watching your channel

[@SalDiBlasi]

Your suspicion is correct, grind it off.

[@minnesotaopinion2833]

So here's my question, I have 3/4 subfloor trusses are spaced 24 inches apart. Do I need to strengthen that for 12x24 tile? It's my bathroom, I demoed an 1.5 inches of concrete and tile out.

[@kellyemarkowski2461]

Hi Sal. Great video on floor joist span required for various types of flooring. I do not see the deflection calculator link. It would be great if you could post that. How do you reinforce the floor joists if the basement ceilings are finished? Would one method be to pull the subfloor and sister the joists from above? Is this a possible solution?

[@SalDiBlasi]

Here are the links, you can also find them in the description of this video Tile Geeks App Android play.google.com/store/apps/details?id=com.ionicframework.tg3726017&hl=en_US Apple apps.apple.com/us/app/tile-geeks/id1193017374

[@politicalpartyagnostic268]

Sal, I really appreciate that you are a logical no B.S. guy. You always present solid useful info!! Thank you!! Merry Christmas sir!!🎄❤️

[@SalDiBlasi]

Merry Christmas.

[@giovannitidona658]

Hi Sal love your Chanel iv learned so much from watching your work could you give me the App. name to calculate deflection

[@SalDiBlasi]

play.google.com/store/apps/details?id=com.ionicframework.tg3726017&gl=US apps.apple.com/us/app/tile-geeks/id1193017374

[@micaonyx5301]

Thanks for the info. I bought marble tiles for my shower. When it was delivered the receipt said that they weigh about 2200 lbs, which I did think about and of course the sales person didn't mention. I asked my contractor if he thought this tiles was too heavy and he said he didn't know so now I'm afraid to install them. Also all of my walls are made of plaster over drywall, which makr them much heavier, so I think my floors are already pushed to the limits. Any advice, please. I know you said talk to an engineer, so would that be a structural engineer.

[@SalDiBlasi]

Your tile is distributed over a very large area, so it is not as if you are putting a 2200 pound point load on one spot, most floors are engineered to accept a ceramic tile floor and meet L/360. The issue is more that you need a stiffer floor and a double layer of plywood for the marble tile. Floor has to meet L/720, in most cases floors will not be that stiff. So yes talk to a design professional that is able to tell you what you need to do to bring your floor up to spec. It is the job of the builder, architect or engineer to figure these things out, it is not the responsibility of the tile guy to determine the strength and deflection of a floor. However a good tile guy will check to have some idea of what he is dealing with.

[@paulpierce2051]

I got that app, but I have engineered joices. Is there a way to have an equivalent?

[@elitetilinguk3757]

Hi Sal. Just a quick question. How do you adjust the deflection calculations for different subfloor materials/thicknesses?

[@SalDiBlasi]

It calculates the deflection of the joist structure, not the subfloor layers.

[@scal760]

Can you do one on floor truss joist

[@kevinbennett3645]

Quick question if you have a moment Sal. How would plywood subfloor affect the calculations? Renovations in my area normally have 1/2" plywood subfloor. We normally add 1/2" ply to increase the strength of the subfloor and then an uncoupling membrane. I would appreciate your thoughts. Thank you.

[@SalDiBlasi]

You need to get a hold of a TCNA handbook. 1/2" plywood is never allowed as a subfloor, I would suggest you use 5/8" instead of 1/2" for the second layer that you add. The requirements of the joist structure do not change. I am not an engineer, however from what I understand, the joist deflection is the amount the entire joist will bend over its length, which is independent of the amount the plywood will bend between the joists. 1/2" plywood is not suitable and installing another layer of 1/2" will have a marginal improvement if they are not glued together to create one solid layer of plywood. Just adding some liquid nails between the two layers introduces voids between the layers, so the entire surface of each layer would need to be bonded to the other to be effective. Again, I am not an engineer so my understanding of how it all works is limited. Probably a good idea to talk to someone that can explain all the physics behind it, so you will be sure of a solution when you encounter this situation.

[@kevinbennett3645]

@@SalDiBlasi Thanks Sal. I appreciate you taking the time to answer this. Very impressed with your work and willingness to share your knowledge. Thank you.

[@stevebeaulieu2617]

Sal: When you screew the second layer of plywood over the subfloor, do you screew that second layer in the joist or just between the joists ? My joists are at 16'' center. If it's screew just between the joists how may screew will you put in a row between two joist ?

[@SalDiBlasi]

Go to page 18, everything you need to know is there www.contractorsdirect.com/PDF/ditra-installation-handbook.pdf

[@Antekdzi1]

Great Video Sal, I have a little question, I measured using the calculator and its about 360, but issue is my ply subfloor is 3/4" and I dont have a lot of room to add more because then the tiles won't be flush with the hardwood floor in the hall. Do I absolutly need to have 1 - 1/8" plywood if I'm comfortably above 360? If I do, can I add reinforcements from underneath as the subfloor is exposed from the basement? Thanks!

[@SalDiBlasi]

You do not need a second layer of plywood if you are not installing a natural stone tile, which would require L/720 anyway. Install a cement board or an uncoupling membrane over your 3/4" subfloor and you are good to go. I would suggest an uncoupling membrane over a cement board, much better system for floors. Here is the ditra handbook for reference. Page 4 is probably for you if your joists are 16" on Center. www.contractorsdirect.com/PDF/ditra-installation-handbook.pdf

[@ginacirelli1581]

Hi Sal, is a stone rating necessary for quarry tile or would that be the same as ceramic/porcelain?

[@SalDiBlasi]

Quarry tile is an unglazed extruded ceramic type tile.

[@briancoleman5453]

Sal, Our bathroom floor is construction tongue-in-groove 2x6 (1974 construction) the boards are 6 3/4 x 1 1/2. We replaced a ouple of them due to dry rot, and replacement is only 5 x 1 3/8. Is there a recomendation to know if this construction is strong enough? (The span is 48 inches from beam to base plate).

[@SalDiBlasi]

Punch your numbers in here www.johnbridge.com/vbulletin/deflecto.pl

[@dr6638]

Excellent video! I used the app and my deflection was 377. I installed porcelain floor. What i noticed is at one spot in the floor I noticed a bounce occurs. Only one area. Could that mean that I am on the edge of the deflection or should I attempt to go below to install some shims or bridges? I just making sure that the tile floor lasts and I will have no trouble going forward. What is my best option?

[@SalDiBlasi]

Have to consult an engineer to figure that out, beyond the scope of what a tile guy is supposed to do.

[@dr6638]

No I have not reached out to an floor engineer. Anything I can check prior to doing so or any suggestions? Thanks

[@kamilzieba7427]

Pretty soon we're going to be checking for deflection to install carpeting...

[@SalDiBlasi]

You can ignore this advice if you like, many do, many regret it. This has always been the case for ceramic tile, it is not a new thing.

[@mattcraztex9940]

Great app. The app is paid for 5.49$ so its not free but a small price to pay for a investment like a Tile floor.

[@carolharris810]

Hi Sal. I have a small two-story condo with small upstairs bath. I am having to redo all tile, bath, toilet and flooring. The vanity are has carpet and the shower/bath tile. I have had to pull out all the tile and would like to replace the carpet in vanity with tile too. Here is my question. When I calculate the deflection, the number I get is is 307 which is less that the needed 360 for tile in upstairs. The total area in question including bath/tub/toilet/vanity is only about 40 square feet. Will tile still work, or do I need to keep carpet in the vanity section? I presume the tile in bath tub toilet area is okay cuz there used to be tile there. But what about the vanity area. The total square footage of my upstairs is probably about 480 sq. Ft and downstairs about another 540 square feet. Thanks so much!

[@SalDiBlasi]

That is way short of the required 360, so best to talk to a structural engineer or other design professional that can tell you how to strengthen your floor.

[@truetrinity333]

Hi Sal! Thanks so much for these videos. The app you suggested doesn’t have the exact measurements for my joists and my joist spacings vary. My joist length is 11 feet, the joists themselves are 7.6x2.6 (so 3x8’s), and joints spacings vary between 12”-14”. If I put in to the app - 7.25” joist height, 2.5” joist width, 14” joist spacing, and 11’ joist length I get 549 for my deflection. BUT if I shift my joist height to 8” I get 704. Shift the joist spacing to 12” as well and I get 821! So my question is: considering that the app does not have my exact measurements for the joists, and there is variations in the joint spaces could I deduce that I might just make it to 720 deflection to be able to use stone tile (slate)? Would using the schluter ditra be the way to go here to ensure that my floor can sustain the weight? Thank you!

[@SalDiBlasi]

Try averaging out the spacing and see what you get. Only an engineer can tell you what your deflection actually is, so I would not presume to tell you what it might be.

[@truetrinity333]

Sal DiBlasi Makes sense. Thank you!

[@carlwilson1483]

Thank you for this Sal. I may need it for a terrible customer.. she is accusing me that her floor is not strong enough for the tile I installed. 2x12s every 16 inches on a 10 foot span. and telling the contractors board im suggesting something that is unsafe for her house. She is really trying to not pay me.. owes me 11k and trying to take me to the board for everything you can imagine saying the most terrible things about me. I am thinking about closing my business now bc I realize that any customer who doesn't want to pay me can complain to the board and have a full investigation launched into my job with no recourse to the homeowner. People are scummy and want to steal from me all the time. I can't stand it, on top of all the bills I have to pay to stay in business here in CA. It's really hard right now Sal, my third year in business. I commend you for your success brother.

[@SalDiBlasi]

Sorry to hear about your trouble.

[@rinotidona952]

Hi Sal i installed 6x24 plank tile over partical board ,rescrew ,tight no sqeeking , rolled on a primer ,and morted in a ditra mat with proper trowel ,JOIST 2x8 16 on center 14 foot span , is that ok its main floor in house ,back room .kitchen ,frontroom oh subfloor is 3/4 OBS EXTERIOR GRADE

[@rinotidona952]

Tile is porcelain

[@hakanozdemir6113]

Hi Sal. I have a double joisted floor that i will be putting marble onto the floor and walls which an engineer has confirmed ok. I was thinking of a wet room but I'm worried about any movement that can cause water to come through the grout

[@SalDiBlasi]

Marble requires a double layer of plywood even if the floor meets L/720, water will always get through the grout, it is only a filler, not a waterproofing element. Your wet area should be water tight before any tile is installed, and your thinset coverage should be 95% or better. I have done many natural stone tile installations in showers and wet areas, as long as you use proper methods and standards and use a suitable stone, it is perfectly acceptable.

[@hakanozdemir6113]

@@SalDiBlasi I have used 1 layer of marine ply wood. I was thinking if using Schluter DITRA-HEAT-DUO Matting and tanking the floor with some tanking paint and then using underfloor heating pipes that slot into the gypsom board. Are you saying I still need two layers of plyboard on the floor? I was thinking of using a wet room shower try that sits on the joists so it's now profile. Ant thoughts on these methods? Could you point me to a video you have made that does exactly that please

[@SalDiBlasi]

@@hakanozdemir6113 I think you need to come up with another plan and yes the second layer of plywood is still needed. Tanking the plywood is a step not needed, the Ditra can be made waterproof very easily, Ditra heat duo is also a thermal break, so you need to have heat on the top side, it also has has no real value over a plywood subfloor, Concrete floors benefit the most.

[@hakanozdemir6113]

@@SalDiBlasi thank you Sal

[@FixItWithMe]

Is the joist structure usually the same in the basement as on the second floor??

[@valeriykolbasov1356]

Sal, what is a way to get deflection in a house where basement is finished and you cannot see beams? And how get a deflection in a condominium unit?

[@SalDiBlasi]

You have to find a place where you can get a look, most times there is a spot somewhere, or you have to find the information another way, ask the condo association for the drawings, do some investigating.

[@valeriykolbasov1356]

@@SalDiBlasi Thank you very much Sal for answering.

[@bono894]

I'm installing 16 x 16 natural stone tile in my kitchen. I have a narrow floor area of 3 joists underneath the floor where their unsupported span is 14 feet. The rest of the joists' unsupported span is well under that distance because of wall studs for rooms under the kitchen. The joists are 2 x 10s spaced 16 inches on center and have metal x supports in the middle placed perpendicular to the joists about 8 feet from the wall. Would I need to put a support beam in the middle just for those three joists or do you think that the existing supports are enough?

[@SalDiBlasi]

So I put your numbers into the deflection calculator and it came up with a deflection of 379. Going by that calculation and the numbers provided, your floor should support a ceramic or porcelain tile floor when an appropriate underlayment is installed. However you indicated that you want to use a natural stone tile which requires a deflection no less that L/720, which your floor does not meet. Beyond that regardless of the deflection, a second layer of plywood in conjunction with an appropriate underlayment is needed. To answer your question, you need to beef up the floor structure to bring it up to spec. for a stone floor. I am not an engineer, so you will need to consult with someone qualified to make the calculations and tell you how to strengthen your floor to meet the minimum requirements.

[@bono894]

@@SalDiBlasi Thanks. I'm thinking of nailing together 2 x 4's to make three separate beams to go under each joist close to the middle so that there would be no more than 8 feet of unsupported span on either side give or take. I calculated it out to L/1389. I'm not an engineer but this seems like a viable solution.

[@SalDiBlasi]

@@bono894 If you feel confident, then it is your call, I can only put the numbers in the app and see what they come out to be. It is never the tile guys job to determine how a structure should be modified to increase the strength.

[@bono894]

@@SalDiBlasi Last question. Would it be okay to fix a structural issue such as mine after the tile is already installed or is it absolutely critical that it be done beforehand?

[@SalDiBlasi]

@@bono894 I would do it before.

[@FixItWithMe]

If there’s only 4 travertine tiles are slightly “bouncy” in a second floor bathroom, how can I fix this? The grout around the tiles are breaking into pieces. I don’t want to re-grout until I figure out what’s causing the problem. Thanks!!! :)

[@SalDiBlasi]

Floor structure is probably not rated for natural stone, my guess is it is a tear out and redo bringing the floor deflection up to L/720 before installing the stone.

[@breikowski]

What about adding to the subfloor? Like an extra 3/4” plywood?

[@mozarkoutdooradventures3630]

Bob Reikowski Good question. A sheet of plywood will do two things. 1. It adds weight 2. It adds stiffness. The stiffness of a sheet of plywood laying flat has very little stiffness and alone and can’t support much weight without deflecting a significant amount. Attaching it to a subfloor will result in an increase in stiffness overall at the cost of added weight. Without doing actual calculations I would not recommend this as a stiffening method. Because, the added stiffness will most likely not be sufficient. Like Sal said, to really know requires calculations for your particular application which should be left to structural engineers.

[@robhashemi3559]

I recently took a Schuter Training Course #1, and they said that it if the subfloor was plywood and needed to be reinforced bc of deflection, that a second plywood subfloor could be installed, but STAGGERED on the joists. check with Schluter on the specifics of this question.

[@RandomxCheese]

On the app there is no option for "I" beans made of plywood. So I pick unknown wood but in good condition?

[@tilegeeks5233]

The ap doesn't have I beams as there is no exact standard for them. The only real way to determine their deflection is to find the manufacturer of them and go to their website to get the data that they publish on the ones used in the home.

[@MrLutzyboy]

I also have Engineered I-beams. Better stiffen that top layer up!

[@BODGE71]

Sal, when you refer to the subfloor are you talking about the flooring that sits directly on the floor joists? If you are, then wouldn't you lay another layer of plywood on top of the existing floor to tile onto and wouldn't this stiffen up the floor (dependent on the thickness of the plywood) and if so is there any way of calculating the stiffness of the floor with the extra floor layer?

[@tt7hvn]

Adding another subfloor would not add rigidity or structure to the existing joists, only more weight on the joists. What he's calculating is the amount of weight (or deflection) the joists can handle since tile is extremely heavy.

[@SalDiBlasi]

The joist structure has to be such that it meets the L/360, If it does you can add your underlayment to the subfloor, be it backer board, uncoupling membrane etc. and then install tile.

[@jons7054]

It's not because tile is heavy, people and things on top of the tile are heavy. If the joists and subfloor flex too much when heavy things move across them or placed on them, your tile will crack.

[@BODGE71]

Thanks guys for the replies. Much appreciated.

[@pwhsbuild]

Adding another layer (glued and screwed) would stiffen the subfloor from joist to joist. Example: if you had L/360 on 3/4" plywood/osb at joist spaced 24" apart, you may be able to raise to the needed value by adding another layer of subfloor (NOT just by adding cement board or other membranes). No matter how thick of plywood/osb you added, it would NOT improve the L/value if the JOIST, only the subfloor itself on the amount of deflection between joist. Weyerhaeuser has some good information on their website for more info on deflection tables etc.

[@jonathanbell9349]

I suppose if your deflection is under 360, you could install larger format tile like 24x48 no? It would span across the joists.

[@SalDiBlasi]

Size of tile does not matter, L/360 has to be met.

[@jonathanbell9349]

@@SalDiBlasi Thanks Uncle Sal:)

[@ofrimashiah2]

Hi sal i have a problem hope you can help. I bought 2.2 pound of grout in a box. Got it in a powder form. Added water so i got maybe drywall compound consistency. Now i let the grout 48 hours today and its still like not happening. I can take a screwdriver and break it from the grooves between the tiles. Where is the problem. I didnt wait the 5 mins like they say but i mean is it that important?

[@ofrimashiah2]

They say on the box 24 hours till it dries and 7 days for full strength. I need maybe 10 sq ft. Just to patch a few spots by the way

[@SalDiBlasi]

Cement products need time to cure, mixing according to directions is very important. If you added water after it has slaked to make it looser, that will affect the strength quite a bit. I would suggest you call the manufacturer for advice,

[@ofrimashiah2]

@@SalDiBlasi yea probably something with the water. Because i saw how professional mix and the consistency and its pretty much the same. Yours wont be powdery at the top at all? Even after less than 24 hours?

[@robertr7887]

Hi sal, i am not able to find the app that your using. There are toó many toó choose from. The app that your using looks pretty simple compare to the ones i ve seen. Can you tell me the complete app name? Can you guide me in the right direction?...thank you

[@SalDiBlasi]

There is a link in the description.

[@robertr7887]

@@SalDiBlasi found it thank you sal! Keep up the good work!

[@Hhhhhhlllll]

www.johnbridge.com/vbulletin/deflecto.pl

[@460sw3]

I feel like this is one of the most overlooked parts of a tile install weather a DIY or a actual "installer". I recently walked away from a potential job I got a call to look at because it was a rather large bathroom, second floor and no way of knowing the stud structure and spacing. Just told them politely no thanks and why....what do you do in this situation Sal? Is their a way I could have figured it out without pulling up floor and subflooring just to find out it couldn't be done?

[@apex007]

you should be able to tell by walking the floor and seeing if you have bounce. But you sound like a seasoned pro who has the ability to decline jobs as you stated.

[@SalDiBlasi]

Sometimes it is hard to tell, I will usually look in the basement, see how the house was constructed, If they have floor vents, you can sometimes get a look at it there. You have to do some investigating.

[@apex007]

@@SalDiBlasi this guy just walks away when he doesnt know what he's doing. I think the homeowner dodged a bullet. God forbid he stand on a ladder and knock on the ceiling to figure out where the joists are.

[@apex007]

@@460sw3 Please don't put your name on anything. Your problem solving skills are zero to none.

[@460sw3]

@@apex007 no, I just won't screw a client over. I told her the truth about the only way we would know what deflection is and that if it didn't meet requirements that now she would have a party demoed floor. That's how I do business.....and I have quite a bit. More than enough to keep me busy, and it's all by referral. And I get to fix or tear out and replace a lot from folks like you that obviously dont know what you're doing. And dont care about you're customers. It's ok though.....its job security for me, keep hacking brother. Hope you carry good insurance

[@dllanzy]

Hi sal, I’m remodeling 2 bathrooms. Originally my contractor said to put concrete board down over the plywood then tile. Plywood is at least 3/4in. Now we are going to add a heated floor. Would Ditra heat work in replacing the concrete board? I’m worried about the floor build up. Thanks, love your work.

[@SalDiBlasi]

Yes, Ditra heat in place of the backer board, Ditra Heat membrane is an uncoupling mat that accepts a heat wire, no need for the backer board.

[@dllanzy]

Ok great. Thanks sal. Wish you lived in Pittsburgh.

[@markguagenti9342]

Hey Sal, I’ve come to a crossroad that I’d like to open dialogue on. Haven’t seen many tile experts talk much on first course of tile at the bathtub flange because often majority of tubs aren’t flat let alone installed level. Also, the first line of tile up against a bathtub on the floor as this is similar due to the tub not being flat or straight from end to end. Would you like to expand or is this a question you can touch on via email. Have you made a video on this? Just trying to master my craft job by job. PS- I have methods I use but would like to see if minds think alike 👍🏼

[@SalDiBlasi]

Always leave a small gap to be caulked at the tub, follow the contour keep it neat and tidy.

[@markguagenti9342]

Thanks Sal, that’s awesome reassurance. That’s what I’ve been doing. Thank you for taking the time to respond I’m sure you’re busy and I’m grateful! Happy Holidays!

[@SalDiBlasi]

@@markguagenti9342 😀👍

[@dustinscroggins3382]

So what was the name of that app

[@ZackyesRno]

The name of the app is in the description of the video.

[@SalDiBlasi]

Like Zack said

[@deathreaper1989]

Great Video Sal, and I downloaded the TILE GREEK APP as well . it is works well and saved my so much of my time . But, Question "People are saying Tile installed over wood floor systems MUST have a minimum of 1-1/4 inches of solid material beneath it. This means you can have a 3/4 inch wood subfloor covered by 1/2 inch plywood, cement board, or approved gypsum fiber underlayment. " Is this true ? The reason why I am asking this , its B/C the floor what we working on is 5/8 (19/32) plywod , Just assuming if i am adding a 1/2 of the cement board above the subfloor , I will still need 1/8 inch. I calculated the Deflectiong is 396 and it should be good for install porcelain tiles. I am thinkg if I could just install the porcelain tile aove the Schulter Ditra XL instead of 1/2 hardie board. which way would be the best ? thank you

[@SalDiBlasi]

The 1 1/4" is if you are using plywood as your underlayment, so you add 1/2" plywood and then install tile directly to the plywood, not the best idea, however there is a method in the TCNA handbook that covers it. For porcelain tile, the underlayment, Ditra, Cement board or whatever you decide to use, can usually be installed on the subfloor and then the tile installed on that. Always follow proper methods and manufacturer recommendations. Natural stone is a whole other story.

[@deathreaper1989]

@@SalDiBlasi Thank you !

[@ZackyesRno]

Taking your most important advice and subscribing.

[@SalDiBlasi]

Thanks 👍

[@skiprope536]

This is painful!

[@SalDiBlasi]

Take some advil.

[@skiprope536]

@@SalDiBlasi Sal Seriously. Your videos are painful. I know you want to help but....

[@SalDiBlasi]

Well you seem to be one of the very few that has a problem, 53 million views seems to contradict you assessment.

[@skiprope536]

@@SalDiBlasi Just goes to show you there are 12K idiots out there. of which you probably have viewed 11K

[@SalDiBlasi]

You mean 128K. So one has to ask, if the whole world thinks it is right, and one guy thinks it is wrong, then is that one guy the idiot, or is the whole world being fooled. Does not matter, the one guy still is an idiot to the rest of the world.

[@creative_vlad]

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