Prepping subfloor? [Archive] - Ceramic Tile Advice Forums - John Bridge Ceramic Tile


View Full Version : Prepping subfloor?

01-11-2011, 01:03 PM
I am getting ready to tile my laundry room which now has vinyl floor. I am planning on taking it and the the backer it is glued to out. At this point i will be down to the subfloor. Our house is about 7 years old and the subfloors are still in very good shape. I had planned on just sealing up the floor with some primer and laying the tile. Will this work or do I need some kind of backer board? If I do need a backer board does anyone have any tricks on getting it to come out level to the ajoining room? Right now if i lay the tile on the subfloor they will be prefect.

Sponsored Links

01-11-2011, 01:08 PM
You need some sort of underlayment. 1/4" thick backerboard is one option. 1/8" thick Ditra or 1/16" Noble CIS are others.

There are no tricks. You set the tile in such a way as to make for a long lasting installation, then you make transitions at the doorways to adjacent floor levels. What you use depends on the adjacent floor finish. Hardwood floors are easy, since you can easily make a tapered transition strip. Carpet can be ramped up to the tile with cedar shingles or "Carpetshims" (google it).

Have you checked to see that the joists are suitable for a tile floor? Use the Deflecto tool in the blue tool bar.

What type and thickness of subfloor do you have? How many layers?

01-11-2011, 01:51 PM
I am not sure of the thickness of the subfloor, but I am sure it is just one layer we just built the house 7 years ago. I used the deflecto tool and got this L / 318. Not sure exactly what this means as far as what I should use on floor.

01-11-2011, 01:55 PM
Was your house permited and inspected? If so, the joists should be OK, even though our deflecto tool says no. It's conservative and was designed when the rules said "L/360 or else." Now the rules say the floor must be built in accordance with local building codes.

The subfloor is a different story. The underlayment guys have final say as to what's acceptable. Pull a register, look at the underside of the subfloor for a grade stamp, or drill a hole somewhere out of the way, but find out about your subfloor.

01-11-2011, 02:12 PM
I just checked the subfloor is 3/4 inch. The joist should be very much to code they are very strick in our county.

01-11-2011, 02:18 PM
Great! Now decide on your underlayment.

01-11-2011, 02:34 PM
Is there a better choice of underlayment for a laundry room, since it has the washer and dryer vibrations on it?

01-11-2011, 02:42 PM
Any one wil do. Backerboard gives the floor more mass, which helps dampen vibrations.