FAQ
FAQ
When framing a Schluter®-KERDI-BOARD-SN shower niche with Schluter®-RONDEC, do I use inside or outside corner accessories?
Can Schluter®-DITRA be used as a sound control membrane?
DITRA is not intended to be barrier sound control system. DITRA does, however, provide a degree of sound attenuation similar...
Can Schluter®-DITRA and Schluter®-DITRA-XL be installed over vinyl flooring?
Yes, Schluter®-DITRA or DITRA-XL can be installed over vinyl. Some limitations include the following: 1- Cushioned vinyl is...
Can mosaic tile be used with Schluter®-DITRA or Schluter®-DITRA-XL?
The minimum required tile format for use with DITRA is 2" x 2" (50 mm x 50 mm). Please call Schluter®-Systems...
Is it required to waterproof Schluter®-DITRA and Schluter®-DITRA-XL?
Waterproofing the floor is not required, but can be beneficial in some cases. Today’s construction methods, which include the use of lightweight...
Can Schluter®-DITRA or Schluter®-DITRA-XL be installed over hardwood flooring?
We don't recommend or warranty DITRA or DITRA-XL installation over existing hardwood flooring as it is very unstable and difficult to bond...
Can I use self-leveling compounds over Schluter®-DITRA or Schluter®-DITRA-XL?
DITRA and DITRA-XL were designed and tested for thin-bed ceramic tile and natural stone applications...
If I use a self-leveler on my plywood subfloor, which type of thin-set mortar do I used to install Schluter®-DITRA or DITRA-XL?
We recommend Schluter SET™ , ALL-SET™ , FAST-SET™, or unmodified thin-set mortar on a floor that has been leveled with a self-leveling product.
How much thin-set mortar will be used with Schluter®-DITRA or Schluter®-DITRA-XL?
The estimated thin-set mortar coverage for each membrane is shown below. Coverage may vary with mortar consistency, angle...
What size notched trowel should I use to install Schluter-DITRA and Schluter®-DITRA-XL?
What is the proper thin-set mortar consistency for installing Schluter-DITRA and Schluter®-DITRA-XL?
Using a thin-set mortar that is suitable for the substrate, apply the thin-set mortar (mixed to a fairly fluid consistency, but still able to hold a notch)...
How long do I have to wait before I can install tile on the Schluter®-DITRA membrane?
Once DITRA has been installed on the substrate, tile can be installed right away. No need to wait for the mortar to cure...
What type of thin-set mortar should I use when setting tile over Schluter®-DITRA and Schluter®-DITRA-XL?
Schluter-Systems requires the use of Schluter SET™ , ALL-SET™ , FAST-SET™, or an unmodified thin-set mortar meeting the requirements of ANSI A118.1 to install ...
Why should I use Schluter®-DITRA in my tile installation?
Ceramic and stone tiles are durable, easy to maintain, and hygienic, representing the ideal surface coverings...
I’m planning to install my tile using Schluter®-DITRA. Where do I begin?
The first thing to do is plan out the installation according to the Schluter-DITRA Installation Handbook...
What type of thin-set mortar should I use when installing Schluter-DITRA?
The type of thin-set mortar used to install DITRA depends on the substrate material. For example, to set DITRA over plywood...
Can I use a premixed thin-set mortar to install Schluter-DITRA and tile?
No. Schluter-Systems does not recommend the use of premixed thin-set mortars (mastics/adhesives) in any DITRA installation.
How do I know if the thin-set mortar is modified or unmodified?
In general, unmodified thin-set mortar is a blend of Portland cement, sand, and water retention agents that is mixed with...
Do I need to provide movement joints when I use Schluter-DITRA in my tile installation?
Yes. DITRA does not eliminate the need for movement joints. Movement joints are essential in any tile installation to prevent...
Can I install glass tile over Schluter®-DITRA?
I tried to snap chalk lines on Schluter-DITRA before setting my tile, but the chalk rubs off the plastic easily while I am working. What can I do?
One option is to apply hair spray over the chalk lines. You don’t have to worry about the hair spray acting as a bond breaker because...
I need to remove and reinstall a tile on Schluter-DITRA. How can I do this safely?
If you are in the process of setting the tile and the thin-set mortar is still fresh, simply run your margin trowel under the surface...
What is the difference between Schluter®-DITRA and Schluter®-DITRA-XL?
Schluter uncoupling membranes provide the four essential functions for successful tile installation over a wide range of substrates...
Can I install electric floor warming systems on top of Schluter®-DITRA and Schluter®-DITRA-XL?
Schluter®-Systems does not recommend the installation of floor warming systems over DITRA or DITRA-XL...
What is the minimum stud spacing when installing the Schluter®-DITRA-HEAT-E-HK heating cables?
A cable spacing of 3 studs between runs is standard. However, cable may also be spaced at continuously alternating 3 stud – 2 stud intervals in isolated...
Can Schluter®-DITRA-HEAT-E-HK heating cables be installed on a shower bench?
Yes, DITRA-HEAT-E-HK heating cables can be installed on the top surface of shower benches. Care must be taken to install...
Can mosaic tile be used with Schluter®-DITRA-HEAT?
The minimum required tile format for use with DITRA-HEAT is 2" x 2" (50 mm x 50 mm). Please call Schluter®-Systems...
Can Schluter®-DITRA-HEAT be installed over vinyl flooring?
Yes, DITRA-HEAT can be installed over vinyl. Some limitations include the following: 1- Cushioned vinyl is unacceptable...
Can Schluter®-DITRA-HEAT be installed over hardwood flooring?
We don't recommend or warranty DITRA-HEAT installation over existing hardwood flooring as it is very unstable and difficult to bond...
Can other manufacturer’s heating cables be installed with Schluter®-DITRA-HEAT membrane?
The DITRA-HEAT-E-HK heating cables are specifically designed to integrate with the DITRA-HEAT membrane...
Can the Schluter®-DITRA-HEAT system be installed in an outdoor installation?
No, the DITRA-HEAT heating cables and membrane cannot be installed outdoors. The heating cables are not rated for exterior applications.
How long do I have to wait after the installing Schluter®-DITRA-HEAT to start using the system?
Schluter®-Systems recommends waiting 7 days after grouting before consistent use of the DITRA-HEAT system...
Can Schluter®-DITRA-HEAT be installed over existing tile?
Installing DITRA-HEAT over existing tile may require special considerations. Please call Schluter®-Systems...
I plan to install an electric floor warming system on slab on grade. Are there any available Schluter products that can act as a thermal break?
Why is megohmmeter testing strongly recommended for Schluter®-DITRA-HEAT-E-HK heating cables?
The insulation resistance test is intended to detect very small breaks throughout the cable insulation before, during, and after installation...
Where can I find a megohmmeter to perform the insulation resistance test?
Megohmmeters may be found at local electrical supply wholesalers or online retailers such as Grainger, Mouser Electronics, Amazon, etc...
My megohmmeter is reading OL or I; is this a good reading for the heating cable insulation resistance test?
If your megohmmeter is reading "OL" (over load) or "I" (infinity), these are commonly used readings on megohmmeters...
How do I connect the Schluter®-DITRA-HEAT-E-HK Heating Cables to a Schluter®-DITRA-HEAT-E-RSD thermostat?
For instructions on connecting the DITRA-HEAT-E-RSD thermostat, please reference the Schluter®-DITRA-HEAT Thermostat User’s Guides or...
How do I program the Schluter®-DITRA-HEAT-E-RSD thermostat?
Please see the DITRA-HEAT DHE RS D/BW Thermostat user’s guide for written instructions or see the Tips, Tricks, & FAQ video...
I ran out of room for my heating cables, can I cut them or put them under my cabinets?
NEVER cut or modify the heating cable in any way. This would change the cable resistance, will cause damage to the cable, and could cause cable overheating...
How do I select the correct length Schluter®-DITRA-HEAT-E-HK heating cable for my floor warming project?
The Schluter®-DITRA-HEAT membrane is selected according to the size of the area to be tiled. The DITRA-HEAT-E-HK heating cable is selected...
Why are two floor temperature sensors provided with the Schluter®-DITRA-HEAT system?
Both floor temperature sensors are installed within the tile assembly. One sensor is connected to the thermostat, while...
Can Schluter®-DITRA-HEAT-E-HK heating cables be installed on walls?
What are the restrictions on where I can install the Schluter®-DITRA-HEAT heating cables?
The DITRA-HEAT heating cables cannot be installed under vanities with no air space beneath, bathtub platforms...
Can more than one DITRA-HEAT-E-HK heating cable be connected to the Schluter®-DITRA-HEAT-E Thermostats ?
Multiple DITRA-HEAT-E-HK heating cables can be connected and controlled by a single DITRA-HEAT-E thermostat, if the total current is less than 15 amps...
What size electrical box is recommended for a Schluter-DITRA-HEAT-E thermostat?
We recommend a single gang, deep electrical box or a double gang electrical box with a single gang mud ring to provide plenty...
How do I choose between the 120V and a 240V Schluter®-DITRA-HEAT-E-HK heating cables?
There is no single determining factor. In general, 120V heating cables must be connected to 120V power sources...
Is it required to waterproof Schluter®-DITRA-HEAT?
Waterproofing the floor is not required, but can be beneficial in some cases. Today’s construction methods...
Can I use self-leveling compounds over Schluter®-DITRA-HEAT?
No, any leveling of the subfloor must be done prior to installing the DITRA-HEAT membrane. A major benefit of DITRA-HEAT is that self-leveling...
How long do I have to wait before installing tile on Schluter®-DITRA-HEAT?
Once the DITRA-HEAT membrane has been installed and the heating cables have been embedded within the membrane and tested, the tile can be installed right away...
How much thin-set mortar will be used with Schluter®-DITRA-HEAT?
The estimated thin-set mortar coverage is shown below. Coverage may vary with mortar consistency, angle at which the trowel is held...
Do I need a GFCI breaker for the Schluter®-DITRA-HEAT system?
What is the proper thin-set mortar consistency for installing Schluter-DITRA-HEAT?
Using a thin-set mortar that is suitable for the substrate, apply the thin-set mortar (mixed to a fairly fluid consistency, but still able to hold a notch)...
How do I connect Schluter®-KERDI-BOARD to a bathtub?
There are two methods to seal KERDI-BOARD to a bathtub. Please refer to the Schluter®-Shower System...
What type of thin-set mortar should I use when setting tile over Schluter®-DITRA-HEAT?
Schluter-Systems requires the use of Schluter SET™ , ALL-SET™ , FAST-SET™, or an unmodified thin-set mortar meeting the requirements of ANSI A118.1 to install...
How long do I have to wait before I can install tile on Schluter®-KERDI-BOARD?
For most installations of KERDI-BOARD, tile can be installed right away. Exceptions include curved wall areas and non-bearing...
What is the R-value for Schluter®-KERDI-BOARD?
R-value is a measure of thermal resistance used in the building and construction industry, which depends primarily...
Can I install glass tile over Schluter®-KERDI-BOARD?
Glass tiles are unique products and may require special consideration. Please call Schluter®-Systems...
Are there accessories available for my selected profile (e.g., end caps, corners, or connectors)?
This depends on the particular profile chosen. Accessories are listed in the Schluter® Illustrated Price List with the products...
Once my tile is installed, it will be higher than the adjacent carpet. What profile would you recommend for this uneven transition?
The Schluter®-RENO-TK profile provides a sloped transition between the tile and carpet and features a channel below...
The tile I’ve chosen for my floor doesn’t have a matching cove base available. I’d rather not select another tile. Do you have any solutions?
Yes. Schluter-Systems offers various profiles that allow the user to produce a finished tile base with a cove...
How do I know which profile size to use?
Profile size selection is based on the thickness of the tile and amount of setting material used to set the tile...
How far from the wall is the KERDI-LINE linear drain installed?
It is installed directly against the wall, so that the channel body support is in contact with the wall. The drain...
Can the Schluter®-KERDI-BOARD-SC prefabricated shower curbs support the weight of a glass door or glass block wall?
Yes, these curbs will support these installations.
How far up the wall do I need to install the Schluter®-KERDI?
For showers and bathtub surrounds, KERDI must be carried to the height of the showerhead at minimum...
What size notched trowel should I use to install Schluter®-KERDI?
A 1/4" x 3/16" (6 mm x 5 mm) V-notched trowel or the Schluter™-KERDI-TROWEL is recommended..
How do I seal Schluter®-KERDI to a bathtub?
There are two methods to seal KERDI to a bathtub. Please refer to the Schluter®-Shower System Installation Handbook...
How long do I have to wait before I can install tile on the Schluter®-KERDI membrane?
Once the KERDI membrane, including seams, corners and protrusions have been completely bonded and, therefore, waterproofed...
I installed my Schluter®-KERDI membrane yesterday. Why is it so easy to peel it off the wall today?
Thin-set mortar takes time to cure. The bond strength will increase over the first week and month after installation...
Can I connect an ABS Schluter®-KERDI-DRAIN bonding flange to my PVC waste line, or vice versa?
No, connecting the different plastics violates plumbing codes. ABS must be connected to ABS and PVC must be connected...
Can I use another manufacturer’s drain with your Schluter®-Shower System?
The Schluter®-KERDI-DRAIN, Schluter®-KERDI-LINE, Schluter®-KERDI-LINE-VARIO drains are specifically designed to integrate with the Schluter®-Shower System...
Can ceramic tile, including porcelain tile, be set on Schluter®-KERDI with latex-modified thin-set mortar?
In general, we DON’T recommend it.
Here’s why:
Latex-modified mortars must dry for the polymers to coalesce and form a hard...
Can I use Schluter®-KERDI in my steam shower?
Yes. KERDI is suitable for use in intermittent use steam showers. Schluter®-KERDI-DS is required for continuous use steam rooms...
My shower isn’t the same size as the Schluter®-KERDI-SHOWER-T/-TS/-TT trays. Can I modify the tray to fit my shower?
Yes. The KERDI-SHOWER- T/-TS/-TT trays can be cut to size to fit various applications. Ideally...
What type of thin-set mortar should I use when installing Schluter®-KERDI?
The type of bonding mortar used to apply KERDI must be suitable for the substrate and must penetrate and engage the membrane fleece...
What type of thin-set mortar should I use when installing ceramic and stone tile over Schluter®-KERDI?
Schluter-Systems requires the use of Schluter SET™ , ALL-SET™ , FAST-SET™, or an unmodified thin-set mortar meeting...
Can I use a premixed thin-set mortar to install Schluter®-KERDI and tile in my shower?
No. Schluter®-Systems does not recommend the use of premixed thin-set mortars (mastics/adhesives) in any KERDI installation.
I accidentally poked a hole through the Schluter®-KERDI while installing the membrane. Do I need to start over or can I simply repair the hole?
Holes can typically be repaired by installing a patch of KERDI or Schluter™-KERDI-BAND with...
What is a water test? How do I perform one on the Schluter®-Shower System?
A water test is a quality control check performed on any shower installation before setting tile. It consists of stopping...
What is the proper thin-set mortar consistency for installation of Schluter®-KERDI/-KERDI-DS?
When installing KERDI/-KERDI-DS the unmodified thin-set mortar is mixed to a fairly fluid consistency, but still able to hold a notch...
Does Schluter®-KERDI waterproofing membrane have a front/back to it?
No, the KERDI membrane does not have a front/back to it. One side of the membrane features printed gridlines...
Do I install the Schluter®-KERDI-BOARD-SC shower curb or Schluter®-KERDI-BOARD-SB shower bench on top of or adjacent to the Schluter®-KERDI-SHOWER- T/-TS/-TT shower trays?
The KERDI-BOARD-SC shower curbs and KERDI-BOARD-SB shower bench are typically installed adjacent to the Schluter prefabricated shower tray...
I purchased a standard Schluter®-KERDI-DRAIN bonding flange with a 2 inch outlet; I now need the adaptor ring for an existing clamping ring drain. Will I be able to use this KERDI-DRAIN flange with the adaptor ring?
No, the KERDI-DRAIN bonding flange is not compatible with the KERDI-DRAIN adaptor ring. You will need to use a KERDI-DRAIN...
How thick are the Schluter-KERDI-SHOWER shower trays?
Below are the charts with the dimensions and perimeter height of each of the KERDI-SHOWER-T/-TS/-TT,...
Can I install glass tile over Schluter®-KERDI?
Glass tiles are unique products and may require special consideration. Please call Schluter®-Systems...
How do I install the prefabricated shelf in the Schluter-KERDI-BOARD-SN shower niche?
When using the KERDI-BOARD-SN prefabricated shelf, determine the desired height of the shelf and mark with a level line...
Can I install Schluter®-KERDI over drywall in my tiled shower?
Yes. Once you install KERDI over the drywall panels, they will be completely protected from the water and vapor in your tiled shower.
I’m installing Schluter®-KERDI over drywall in my shower. Do I need to tape the joints between panels before installing the KERDI?
No. It is not necessary to tape the joints between drywall panels before installing KERDI. If you must tape...
What are the Schluter®-KERDI-SHOWER and Schluter®-KERDI-BOARD prefabricated substrates made of? Can they really support the tile assembly?
The KERDI-SHOWER prefabricated substrates are made of expanded polystyrene (EPS) foam with a high compressive strength...
Can the Schluter®-KERDI-BOARD-SC shower curb be trimmed to my desired size?
The Schluter®-KERDI-BOARD-SC shower curbs can be cut to length using a utility knife or a handsaw. To modify the height, remove the desired amount from the bottom of the curb using a utility knife...
Can the Schluter®-KERDI-BOARD-SB be trimmed to my desired size?
Yes, the KERDI-SHOWER-SB shower bench can be trimmed to the desired width using a utility knife...
What is the difference between modified and unmodified thin-set mortar?
Dry-set mortar is comprised mostly of cement, sand, and a water retention agent, and is also called unmodified...
Why did Schluter Systems change its position on thin-set mortar?
We haven’t changed our position on thin-set mortar use within our systems. Developing our own...
Why would Schluter’s modified thin-set be ok to use, but not other manufacturers’ modified thin-set?
The key is predictability. Schluter Systems’ modified thin-set mortars have been specifically formulated to set and gain strength...
Can Schluter ALL-SET® and Schluter FAST-SET® modified thin-set mortars be used to set tile over Schluter boards and membranes?
Yes. All Schluter Systems’ thin-set mortars, including the ALL-SET® and FAST-SET® modified varieties can be used to set tile over DITRA...
Can I still use other manufacturers’ unmodified thin-set mortars to install tile over Schluter boards and membranes?
Yes! We still warrant the use of unmodified thin-set mortar meeting ANSI A118.1 to install tile within our systems...
Can I use other manufacturers’ modified thin-set mortars to install tile over Schluter boards and membranes?
No. Our position on the use of other manufacturers’ thin-set mortars within our systems in general has...
What is the difference between the ANSI standards? Why do some of the Schluter® mortars have more than one standard on the packaging?
More than one standard may apply to the product. a. ANSI A118.1 is the American National Standard...
What is the difference between grey and white mortar?
Certain applications where the color of the mortar affects the aesthetics of the installation may require the...