Ceramic Tile Advice Forums - John Bridge Ceramic Tile

Welcome to John Bridge / Tile Your World, the friendliest DIY Forum on the Internet


Advertiser Directory
JohnBridge.com Home
Buy John Bridge's Books

Go Back   Ceramic Tile Advice Forums - John Bridge Ceramic Tile > Tile & Stone Forums > Tile Forum/Advice Board

Sponsors


Reply
Thread Tools Search this Thread
Unread 06-15-2007, 01:14 AM   #1
diggity
Registered User
 
Join Date: Jun 2007
Location: Renton, WA
Posts: 3
Question Tile over concrete on outdoor patio - need advice

Hello,

My name is Doug and I'm preparing to lay tile for the first time. I've read through a lot of this site and it's been very educational! But since I'm brand new to this, I'm hoping some of you smart folks can help me with a few questions.

First a little background... The project is to tile over a concrete patio in our backyard (near Seattle, WA). The area is about 800 sq ft overall, divided into a few small sections, maybe 20' at the longest dimension. I think I read that expansion joints are only needed over 30', so no concern there. The slab is very stable -- it's 6-8 years old and has no cracks. There is a seam where the original slab was added to - I will need expansion joints here. Water doesn't pool anywhere on the patio and it has a slight slope to it (away from the house).

Tile selection: We have large evergreen trees overhanging the patio, so falling branches and debris is a concern. Based on a few threads I read here, we plan to select a "color through" porcelain/ceramic frost-proof tile with an outdoor texture to avoid slips. We like the look of slate, but since it doesn't stand up to frost well we will look for a porcelain/ceramic look-alike. We like the look of big tiles, so we'll probably go with 12" or 18" square tiles.

Surface prep: The concrete is not sealed. It was previously covered by ~1/2" of terrazzo ("decorative" concrete - if you can call flourescent green and pink decorative), which I chipped off with a jackhammer last year. I think I probably should clean the concrete, so I was planning on pressure washing it. Also, the surface is a little uneven in places, especially at the seam where the slab was added to. I plan to work this with some concrete patch. How level does the surface need to be (how much variance can be hidden away in the mortar)? Any other surface prep, or is it then ready to go?

Membrane: I've read here that I need a membrane to keep the water off the tile. What are my options here? Can I use any old concrete sealer or do I need something more serious? Any product recommendations?

Mortar: Any product recommendations for this? What tile spacing is recommended?

Grout: Anything special here? A girl at the tile store recommended an epoxy-based grout (to keep tree gunk from staining it), but I've heard it is a pain to work with. What do you folks recommend?

Expansion joints: Any product recommendations for this?

Anything else I missed? Thanks in advance for your help!!! It is very much appreciated!
Doug
diggity is offline   Reply With Quote
Sponsored Links
Unread 06-15-2007, 01:22 AM   #2
diggity
Registered User
 
Join Date: Jun 2007
Location: Renton, WA
Posts: 3
Attached is a photo of one of the large areas. It shows the seam I mentioned -- the rectangular area in the middle is original, it was expanded to the half circle shape later.

-Doug
Attached Images
 
diggity is offline   Reply With Quote
Unread 06-15-2007, 06:24 PM   #3
Davestone
Florida Tile & Stone Man
 
Join Date: Apr 2004
Location: Naples Fl.
Posts: 22,690
Doug,technically 1/4" per ft. pitch is recommended,it takes this much to get water to run off,especially in freezing climates, and bumpy tiles.A membrane is used on top the slab, and under the tile,to prevent cracking if and when the slab cracks.You'll need to grind a little bit of the humps off, and fill in the low spots with a straight edge and slc, or wet thinset.I would use a modified thinset,portland cement grout,epansion joint caulk at the house and over the cold joints in the slab,maybe Tec, or Sikaflex,and a penetrating sealer on the grout,Aquamix, Stonetech,Miracle,whichever.
__________________
Dave



http://Davestonestile.com
Davestone is offline   Reply With Quote
Unread 06-15-2007, 08:55 PM   #4
tilerik
Registered User
 
Join Date: Aug 2004
Location: Maine
Posts: 125
Send a message via Yahoo to tilerik
Doug, I would recommend taking a look at schluter.com. They have a lot of great products for that very application, which will eliminate your concerns about cracks and drainage and control joints.
__________________
"Raising the Standard, One Tile at a Time"
Rik B.
tilerik is offline   Reply With Quote
Unread 06-16-2007, 09:02 AM   #5
cx
Moderator emeritus
 
cx's Avatar
 
Join Date: Jul 2001
Location: Boerne, Texas
Posts: 93,583
Welcome, Doug.

The industry standard for movement joints in exterior tile installations is 8 - 12 feet in each direction.

While I'm a proponent of the use of Schluter's products, I must take issue with Rik's claim that they will "eliminate your concerns about cracks and drainage and control joints." You must still adequately address those issues, Schluter or no Schluter.

For certain you must honor those cold joints between the old and new concrete work. And if you find there is any vertical movement between them (likely), you're likely to have a problem tiling over them with any installation method.

My opinion; worth price charged.
__________________
CX

Y'ALL NEW VISITORS READ THIS HERE!
cx is online now   Reply With Quote
Unread 06-16-2007, 09:54 AM   #6
diggity
Registered User
 
Join Date: Jun 2007
Location: Renton, WA
Posts: 3
Thank you for the responses.

I just measured and I do have 1/4" per foot of slope, so that looks good.

Thank you for correcting me to 8-12' between joints - not sure where I got 30' from. Guess I'll need a few more joints than I originally thought.

CX - excellent point about vertical movement. The seams look surprisingly stable - I don't see any evidence of vertical movement, but I will be sure to place a joint over them to be safe.

I assume you folks are recommending Schluter's Ditra -- which does look quite nice, but is rather pricey. Do I have less expensive options here? I want to do this right, but price adds up quickly over 800 sq ft.

Thanks,
Doug
diggity is offline   Reply With Quote
Unread 06-16-2007, 04:30 PM   #7
cx
Moderator emeritus
 
cx's Avatar
 
Join Date: Jul 2001
Location: Boerne, Texas
Posts: 93,583
You want a waterproof membrane of some sort over the concrete if you're serious about the installation being long-lasting, Doug. None of them are inexpensive.

You can, of course, lay the tile directly on the clean concrete if you wanna toss the dice.

My opinion; worth price charged.
__________________
CX

Y'ALL NEW VISITORS READ THIS HERE!
cx is online now   Reply With Quote
Reply

Stonetooling.com   Tile-Assn.com   National Gypsum Permabase


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -6. The time now is 01:21 PM.


Sponsors

Powered by vBulletin® Version 3.7.4
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
Copyright 2018 John Bridge & Associates, LLC