If you’re just joining us, we’ve been working through a series of articles all about installing a tile floor, and I’ve partnered Jim and Rich from Diamond Tile here in Maryland. Jim and Rich are expert tile contractors, and at this point the floor has been “leveled”, DITRA installed, and guidelines marked. Today’s article will showcase how they laid the tile and offer some tips for success.
This article is part of a comprehensive series on How to Install a Heated Tile Floor. If you find the pictures and information helpful, consider giving this article a +1 and sharing it on Facebook.
Previous article: Marking Guidelines for Laying Tile
Step 1: Pre-Cut Tiles
The precise guidelines enabled Jim and Rich to pre-cut all the tile beforehand. This was important because they could work faster, and they could address any difficult areas before laying tile. Otherwise, they’d have a time constraint as Ditra-Set has an open time of about 20 – 30 minutes.
Pro-Tip: Use a grease pencil (a.k.a. wax pencil, china marker) to scribe lines on tile.
Pro-Tip: Always examine the tile for a pattern and orient the tile accordingly.
Pro-Talk: The pattern on a tile is sometimes referred to as the “grain” of the tile.
The guys cut all the tile adjacent to a wall with about 1/16 – 1/8″ gap.
If you read yesterdays article about marking guidelines for the tile, you know that the spacing includes a grout joint in both directions. That means that any given tile is tight against the lines on two sides (first picture below), and the other two sides have an 1/8″ gap (second picture below). Understanding the spacing is second nature for Jim and Rich, but it may be difficult to remember at first.
The guys also cut tiles around the stairs, posts and door threshold.
Pro-Tip: Flattening the floor and keeping cuts tight eliminates the need for shoe molding after the baseboards are installed.
There’s a number of tools for cutting tile like nippers, a grinder or a tile cutter. The guys are still enjoying the Bosch TC10 wet saw (review), especially being able to make plunge cuts. Most of the cuts were straight across. Some of the cuts were L-shaped to go around a corner or U-shaped to fit underneath a door jamb or around a post.
Inside corner cuts are difficult because the cut actually needs to extend slightly past the corner to go through the full thickness of the tile. For these cuts, the guys would start the cut on the face of the tile, then flip it over and complete the cut on the backside of the tile. That way the face of the tile stays intact.
Step 2: Cut Door Jambs
Often door jambs need to be trimmed so that tile can fit underneath. Jim and Rich lay a tile next to the jamb and scribe a line. Next, they usually make the cut with a grinder. However, you can use a flush-cut saw, OMT or a handsaw to achieve the same results.
Pro-Tip: The tile must fit underneath the jamb with a bed of mortar underneath.
Pro-Tip: Jim and Rich sometimes remove the doors to make it easier to work.
Step 3: Mix Mortar
With all the cuts made, Jim and Rich got started on laying the tile, and they began by mixing up some Ditra-Set mortar according to the instructions.
If you’re following along, don’t forget to let the mortar slake for about 15 minutes before remixing.
Step 4: Brush Clean
Jim laid the tile, working in small section, and he brushed each section clean before spreading mortar.
Step 5: Comb Mortar
Jim used a 1/2″ square-notched trowel to comb out an even bed of mortar. He spread the mortar right up to the guidelines, taking care not to obscure the lines.
Pro-Tip: Typically, the guys specify a 1/4″ square notch for 6 x 6 tile, a 3/8″ square notch for 12 x 12 and smaller, and 1/2″ square notch for anything bigger.
Step 6: Set Tile
Next, Jim would lay the tile on the mortar, pressing down firmly to ensure good coverage. At the same time, he was making sure the tile lined up with his guides, and making sure the tile was even with any neighboring tiles.
Step 7: Sponge Clean
After Jim was satisfied, he sponged the face and joints clean, and moved on to the next piece.
Too Much Mortar in the Joints
A common DIYer mistake when laying tile is leaving excess mortar in the joints, and this is a problem because it can show through the grout. Jim has a great trick for removing excess mortar. First, he pushes the tiles together, causing mortar to ooze up out of the joint. Next, he wipes the joint clean and moves the tiles apart. As Jim separates the tiles, the mortar is pulled back down. After one final wipe, the joint is clear and ready for grout.
Uneven Tiles
Every so often Jim wouldn’t be satisfied that a tile was even with adjacent pieces. In these instances, he would use a small, flat trowel to pull the tile up and spread additional mortar along the low side.
Pro-Tip: If you have to stop part way through laying tile, clean up any unused mortar. Otherwise, you’ll have to chip away the hardened mortar when you start again.
Allow to Dry
Give the mortar at least 24 hours (depending on conditions) before walking on the tile.
Next up, I’m covering grouting tile joints so stay with me!
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