Grouting with Epoxy? Multiple Choice Quiz
Tile Installation Dos and Don’ts: How Much Do You Know?
Steve Young
Grouting with epoxy offers many benefits over other methods. The quiz, and the following explanations are designed to drive home some of the benefits and differences between epoxy grout and traditional sanded (and unsanded) grouts.
Epoxy Grouts Do’s, Don’ts and other Crazy Ideas
1. – A Never, ever, ever grout on Friday. Plan to clean up any haze the day after grout is set to keep your customers happy and your reputation intact.
2. – C Epoxy hates cold, loves heat. In hot weather — mix with cold water. In cold weather —mix with hot water.
3. – D How does temperature influence epoxy grout?
In cold weather epoxy is VERY slow to cure and gets very stiff (hard to work with). In hot weather epoxy is more fluid, easier to grout but will set up FASTER. In the end, the temperature of the substrate/tile is actually more important than the ambient air temperature.
4. – A You need the proper tools because epoxy grouts clean differently than cement grout. The proper tools are:
- A grout float with a hard, sharp edge
- Towels
- Scrub pads
- Sponges
- A couple of five-gallon pails
- Detergent
5. – A For best results, mix
by hand to avoid air bubbles. If you’re using a small paint mixer, run on a slow speed, and don’t over mix. Over mixing will shorten pot life and cause air bubbles or pin holes in the joints
6. – B Always pack your joints full. Cut off excess grout with grout float at 90 degree angle, NOT 85 degree or 70 degree angle – that’s why you need a sharp grout float!
7. – B When you are working a vertical face, time is VERY important! Litokol has the best pot life of any epoxy on the market—60 to 80 minutes – which is very important when grouting vertically. Epoxy grouts create heat to cure (see questions 2 and 3), and they need mass to do this properly.
After packing the joints full and cutting excess off the tile, you can begin cleaning immediately using plenty of water and a scrub pad. Do this fast (don’t keep working the surface). Then, drag a damp towel to wipe up the residue—towels clean more area than a sponge.
You now have a number of hours to do your second cleaning and fix rough spots or pin holes. This is done AFTER the joint is firm and not sticky. Using a clean pail of water, liquid detergent (water should feel greasy) and a sponge, go over the area again. You should always go back the next day to check for any haze and do a third cleaning, if necessary. This is why you NEVER grout on Friday!
8. – C Epoxy grouts create heat when in mass, like a pail, which causes faster set up.
9. – C Pin holes are caused by over mixing, but the major cause is voids under the tile.
10. – D Low or uneven joints can have several causes, including water in the grout, and failing to pack the joints full. Perhaps the most common cause is voids under the tile.
11. – C Not changing the cleaning water can cause haze and inconsistent color, but especially in the south you must protect uncured grout from airborne contaminants such as construction dust, pollen, red clay dust, which will turn your (white) epoxy red or green, depending on the contaminate.
1. Why shouldn’t you grout with epoxy grout on a Friday?
A. You may forget to come back the following day to clean any haze.
B. Government regulations.
C. No one works on Saturday.
2. Which of the following are true regarding epoxy and temperature?
A. During hot weather use cold or cool water so as not to soften grout during clean-up.
B. Hot or warm water helps with clean-up in cold weather.
C. All of the above.
3. How does temperature affect epoxy grout?
A. Cold weather epoxies are very slow to set up.
B. Epoxies are harder to work with if they are cold.
C. Epoxy grouts are easier to trowel when warm.
D. All of the above.
4. Why do you need the proper tools when grouting epoxy?
A. Epoxy grouts clean differently than cement grout; all grout floats aren’t created equally.
B. Manufacturers like to sell you stuff you don’t need.
5. Improper mixing of epoxy can cause which of the following?
A. It can cause air bubbles and shorter pot life.
B. It can cause grout to catch on fire and explode.
C. It can cause a color change.
6. Why should you hold the grout float at a 90-degree angle?
A. That is the only way you can hold it.
B. That is the only angle which cuts off excess grout.
7. Working time — why is that important?
A. Working time is not important.
B. Vertical grouting is slower so pot life is important.
8. Why does a full pail of epoxy grout set up faster than the grout joint or haze left on the tile?
A. It doesn’t.
B. It is actually slower to set up.
C. Epoxy grouts create heat when in mass which causes faster set up.
9. What causes pin holes?
A. Over mixing.
B. Improper bedding of the tile.
C. Water in un-grouted joints.
D. All of the above.
10. What causes low or uneven grout joints?
A. Adding water to the grout.
B. Voids under the tile.
C. Not packing the joints full.
D. All of the above.
11. Why would white epoxy turn red or green?
A. Dirty water.
B. Over mixing.
C. Pollen or red clay dust blowing in and contaminating fresh epoxy grout.
Quiz Answers:
1. A
2. C
3. D
4. A
5. A
6. B
7. B
8. C
9. C
10. D
11. C