DekTek Tile's Sister Joist Installation Method is one of the main installation options when installing the concrete deck tiles on elevated decks.
Sister Joist Installation Brochure PDF
Framing For DekTek Tile's Concrete Decking:
Step 1.
Frame joists 16-inches on-center (OC). Add lateral blocking, same width as existing joists, a maximum of 4-feet OC.
Step 2.
A) Add sister joist to each existing joist. If joists are capable of supporting 10.5-pounds per sq. ft. dead load, then a 2x4 sister joist is sufficient. Otherwise, a full-length joist the same size as the existing will need to be added. The deck frame must be able to support a dead load of 10.5 pounds per square foot.
B) Place joist spacers no more than 24 inches apart in between the main joist and sister joist. Use two 16d galvanized nails or 3.5-inch screws to fasten the sister joist to the spacer and into the main joist. Add more 16d nails or 3.5-inch screws every 12 inches through the sister joist.
Add 1/4 to 1/2 inch joist spacer between the sister joist and the main joist to create a gap for better water drainage.
Two 16d nails or 3.5-inch screws need to be fastened into the sister joist at every spacer location, and a nail or screw every 12-inches.
Step 3.
Install the edge trim. Borders must be mechanically fastened at the outside edges to lock in the tiles. The most common border options are wood, composite, anodized aluminum, galvanized steel, or raising the facia board on the side of the deck 7/8" to lock in deck tiles. Border trim against house is optional.
Step 4.
DekTek Tile must be sealed with a high-quality solvent-based concrete sealer. (See sealing video below.) First, apply on all four sides of the tile and then the top of tile before installing. Do not seal bottom of tile. See sealing brochure for more information.
Setting The Deck Tiles
Step 5.
First layout the tile grid plan for overall tile positioning. When you start setting the tile, be sure to choose varied colors from the order to make sure the colors are mixed nicely. The tile must have a minimum of 1 inch bearing on each joist. Please note: Any tile cut to 10 inches or less needs extra support running under the bottom of the tile (i.e. an added 2x4). (See Deck Installation Tips For Planning & Installing Your DekTek Tile Concrete Tile Deck Video)
Tile is then set using a high quality exterior polyurethane adhesive directly to wood joists. Apply recommended adhesive (see adhesive brochure) to the joists as you lay your tile. Space tile joints 1/16 to 1/8 inch apart to allow for water drainage and the expansion / contraction of the tile. The joist spacing created in step 2, should be directly below the tile joints, as shown in the close-up, for the best water drainage. Cut tiles where needed. The tiles easily cut with a wet tile saw.
Tile setting skills are highly recommended.
Setting Equipment Needed:
- Caulk Gun
- 10" Wet Diamond Saw
- Chalk Line
- Tape Measure
For installation questions, please call 218-380-9330 or email us at info@dektektile.com. Thank you!
Sealing
DekTek Tiles should be sealed with a high-quality concrete sealer on top and all sides before installing. Be careful not to apply sealer to bottom of tile. When sealer is applied to bottom of tile it can break the bond of the adhesive.
Do not use a brush when sealing the surface of DekTek Tiles. It would be okay to use on the sides of the tiles if needed but using a brush on the top of the tile will cause brush marks.
Doubling Up The Deck Joists When Installing DekTek Tile’s Concrete Decking Using the Sister Joist Installation Method
Usually when installing the Sister Joist System, you have your main joist (often a 2x10 or 2x12) and then a 2x4 sister joist is added to the main joist to allow enough room for the deck tiles to sit on.
In certain situations however, a contractor or DIYer may need or prefer to double up the joists for added structural support. For example, on a deck remodel located in a state with less stringent framing requirements—such as many southern states that don't need to account for snow loads—if the existing joists are 2x8s spanning 10 feet or more, adding a 2x4 joist alone likely wouldn’t provide sufficient support. In cases like this, where additional strength is required, doubling up the joists would be the appropriate solution.
It is not required to double up the joists for all DekTek Tile deck installations, only when structurally needed or desired.
Important Installation Details:
- "It is essential that the deck frame or supporting structure is properly engineered to bear the weight of the concrete deck tiles, which is a dead load of 10.5 pounds per square foot. In many northern U.S. states, where snowfall is prevalent, if a deck were built up to code, framing is usually sufficient, with the minor modification of adding the Sister Joist or Sleeper System. But again, it’s critical that the framing is specifically designed to support the 10.5 pounds per square foot of the decking tile.
- If you are adding a sister joist or doubling the joists because additional structural strength is needed for the deck tiles, it’s very important that the sister joist or joist added to double up the framing, are fastened to the ledger board and outer beam, not just attached to the main joist itself. This install technique significantly increases the overall structural strength of the deck.
- Whenever you’re building a DekTek Tile deck or outdoor space, ensure that you follow all applicable state and local building codes.
Framing Tip:
If you are unclear as to what size of deck joists you need for your deck installation, you can often consult your local lumber supplier. You will need to provide them with all your deck framing details:
- Deck Dimensions
- The distance the deck framing spans from the house/building to the outside perimeter of the deck.
- The location of the supports and beams.
- It is also important to let them know you will be using a deck tile that weighs 10.5 pounds per square foot.
They should be able to calculate the framing requirements (joists/beams/supports) needed for you.
If you have any additional questions, feel free to contact our team at 218-380-9330 or email us at info@dektektile.com.
Sealers for DekTek Tile
We recommend using a good solvent-based sealer that is for acid stained or stamped concrete. We do not recommend any specific brand. There are many brands of concrete sealers on the market that are high quality. Please feel free to consult your local concrete expert. One brand that we have used with success is "Gator Seal," made by Alliance.
***Water-based sealers are not recommended because they tend to peel. We also do not recommend using penetrating sealers as our tiles are too dense and it does not protect the tile surface.***
***We recommend rolling on a layer of the sealer before you install the tiles, which allows you to coat the edges of the tile for better protection.***
DekTek Tiles need to be sealed every 3 years, especially in cold climates to protect against freeze thaw and other elements. By sealing your tiles every 3 years, this will give you the maximum longevity out of the product.
Gator Seal Sealers:
These sealers are used for the very first application.
Satin Look Finish - Low Gloss
Wet Look Finish - High Gloss
Re-Sealing Your DekTek Tile Deck:
Gator Seal "Resealer"
Whether you use Satin Look or Wet Look sealer on your first initial sealcoat, it is recommended that you use Alliance's Gator Seal "Resealer" on all future sealcoats.
It is common for some sealers to form a cloudy or foggy look after a period of time. DO NOT BE ALARMED, this is a normal occurrence and it is easily fixed:
Remove Cloudiness
Xylene (or Xylol) – For Solvent-Based Sealer ONLY
Use Xylene (sometimes called xylol), and roll it on just as you would roll on another layer of sealer. We recommend one person rolling it on and having a second person back rolling with a dry roller nap to soak up the excess xylene.
Another option, if two people are not available, is for you to roll on the xylene in a smaller area, and then back roll before the xylene evaporates. This method works well for the brand Gator Seal.
If using a different brand of sealer, please check with the manufacturer to see if this system is approved. You can purchase Xylene from your local paint or hardware store.
Make Your Deck Extra Non-Skid
Here are the simple steps to give your deck a non-skid surface. This is recommended for all decks, especially these applications below:
- Decks that get snow and winter traffic
- Decks exposed to a fair amount of water
- Stairs and Steps
- Pool Decks
- Want to take extra precautions
Steps to Give Your Deck a Non-Skid Surface:
- Add a specially designed sand-grit to the sealer, i.e. "Shark Grip". Use the proper amount recommended by the manufacturer.
- Stir sealer and sand-grit together until evenly mixed.
- Apply sand-grit sealer to tile.
- Keep the sealer agitated so the sand doesn’t settle to the bottom.
- Enjoy your Non-Skid deck!
*DekTek, Inc. shall have no liability for defects or damage resulting from application of concrete sealer or surface treatments.* See DekTek Tile warranty.