Porcelain Tile In Kitchen

[JD5210]

I am looking to put down porcelain tile in my kitchen which is 16X24, the house was built in 1996. The joists are No.2 southern pine 2X10 on 16 in centers. One section the joists are 8 foot long and the other section the joists are 16 foot long. Should I be concerned about the deflection of the 16 foot joists?

On the underlayment, I am looking at 1/4 inch wonderboard or 1/2 wonderboard or should I be looking at Ditra?

Would appreciate any help/suggestions anyone has and share anything else you feel I should know about putting down porcelain tile.

Hope this is correct forum to put this under.

Thanks in advance for the help!

 

[dmccarty]

What does the tile make say? They should have instructions on how to install the tile which should mention the underlayment requirements as well as deflection.

Later,
Dan

 

[Ridgewalker]

For what it's worth we looked at tile and ended up going with a product called Alterna Luxury vinyl. Most visitors think its ceramic.
It's much cheaper, easier to install and you don't have to worry about weight. Luxury Vinyl Flooring | Vinyl Plank Flooring from Armstrong

 

[V1Rotate]

I just did a new kitchen floor with porcelain tile. I've got 2 layers of 3/8 plywood then I put down 1/4 inch Hardiboard.(cement board) under the tiles. The floor is as solid as a rock.

 

[dragoneggs]

I assume you have 3/4 or at least 5/8in plywood that you will lay the wonderboard on? Is there a way to put a center support beam under your 16ft span?

 

[Tomtint]

I believe that if you glue and ring nail your under layment ( every 5-5" ) and use a 3/8 trowel for the cement. You will be good to go.

 

[JD5210]

Thanks for the responses. My flooring is T&G 3/4 plywood. Doing more research since my post, I would use 1/2 wonderboard.

I do not plan on putting up additional support under the 16X16, hence my reason for the post to see if others feel I am or am not asking trouble.

Thanks again for the help.

 

[ustmd]

Not a profession builder, engineer or tile installer...I would be a little concerned because those 16ft joists are right at the edge of what the span tables say is acceptable for # 2 2 x 10 SYP.

Maximum Span Calculator for Joists & Rafters

 

[dragoneggs]

Thanks for the responses. My flooring is T&G 3/4 plywood. Doing more research since my post, I would use 1/2 wonderboard.

I do not plan on putting up additional support under the 16X16, hence my reason for the post to see if others feel I am or am not asking trouble.

Thanks again for the help.

With the 3/4 T&G and 1/2 wonderboard I think you will be okay. I have 16" ceramic tile on a 14' span in my dining/kitchen area and zero cracks in grout or tile in five years but I haven't been jumping on it either.
Secure well the wonderboard. Do you have any squeaks on the floor now? If so I would fix those. That would concern me.

 

[dragoneggs]

Oops double post. Seems easy to do on iPhone.

 

[LD1]

Not a profession builder, engineer or tile installer...I would be a little concerned because those 16ft joists are right at the edge of what the span tables say is acceptable for # 2 2 x 10 SYP.

Maximum Span Calculator for Joists & Rafters

Oops double post. Seems easy to do on iPhone.

Its actually probably a tad under the rating if you up the dead load to 15PSF, given that tile+cement board + mortar will likely push it to that.

Another thing to be sure of, is are you positive it is SYP. white pine is a bit softer.

Also, just so you are aware, even though you are at the "max" allowable span, that dont mean the floor cannot deflect. They used L/360 deflection. That means since you are at the max of 16', which is 192"........192/360 is alittle over 1/2" that your floor is allowed to deflect the way it is currently designed. I would be concerned with cracking grout loose with those numbers.

Also, what is under the area that you cannot shore the long span up??

And one final note, I would use a tile that has more of a rougher finish. I dont like that really glazed stuff. Sure it cleans up well, but its like walking on ice if there is the slightest hint of moisture.

 

[JD5210]

Thanks to all that responded. No. 2 SYP is what is stamped on the joists. It looks like I am at the edge or over it. As LD1 point out if I up either the dead load or the live load, it pushes me over the edge.

I am having a Lowes installer come out on Monday, but I am think I will have to go with the oak hardwood. Hardwood was my second choice for the kitchen, on the plus side, it looks a LOT easier to put down hardwood, then tile.

Thanks for your help.