How I Re-Grouted A Shower Floor


How I re-grouted a shower floor for the first time is a story that I thought would be beneficial to some of MrElectrician.TV’s visitors even though it is not related to electrical wiring.  NOTE: Some text links below go to applicable products on Amazon.  As an Amazon Associate I earn from qualifying purchases.

Re-grouting a shower floor is not something that I would normally do for someone other than myself.  I am only set up with tools and materials to do electrical work.  However I committed to helping another human get their home in order and the task was important.

I knew ahead of time that it wouldn’t be a fun project, but the re-grouting of the shower floor was necessary and circumstances called for me to step up and get it done.  Keep reading for how I re-grouted a shower floor.

This particular shower floor re-grouting project was originally intended to be done by a contractor, however it was very difficult to find one who was available.  I called a highly recommended handyman who does re-grouting, but he was not willing to re-grout this particular shower.

The handyman’s reason for not wanting to re-grout this particular shower floor is because the specifications called for the installation of Laticrete Spectralock Premium Epoxy Grout and he only had one experience with it and, according to him it did not go well.  He was willing to just remove the old grout and gave a ridiculously cheap price for that.

Laticrete Spectralock Premium Epoxy Grout is unique in that it consists of three components that must be mixed together and must be used within a limited time frame.

The epoxy also requires the use of household vinegar for clean-up.  The grout bucket with parts A & B is packaged with latex gloves, a tile sponge, and two packets of clean up powder that gets mixed in with your clean up water.  Also included are instructions on how to properly mix and apply the grout.

Part C is the colored sand that gets mixed in after parts A & B are mixed together.  It must all be thoroughly mixed to a cake batter-like consistency.

You must begin applying the grout to the tile immediately after it is mixed.  I recommend that you have all preparations made ahead of time so you can immediately start grouting after mixing.

For the 36 inch x 60 inch shower floor I needed two Spectralock  0.2 US gallon (0.7 Liter) mini kits that contained Parts A and B.  In addition I needed two part C’s 2 pound (.9 Kilograms) colored sand packages.  The color chosen is called mushroom.

NOTE: On their website Laticrete shows part C as being 2.25 pounds (1 Kilogram).  Maybe the batch that I received was older.

Click here for an estimating tool to calculate how much grout will be needed for your tile.

It turned out that the handyman’s cheap price only called for the removal of the loose and broken grout.  It was an extra hourly rate for another hour and a half of labor to do the whole 15 square foot floor (3′ x 5′).  Even then he was not able to remove the grout from the tiles next to the wall because his power tool could not get close enough.


The handyman used a small cordless circular saw with a diamond blade to cut out between the tiles.  It did a good job of removing the old grout, but he also nicked a few tiles with it.  The 2″ x 2″ matted tile had 3/16″ wide grout joints, but due to the slope of the shower floor the installed tile joints were slightly closer together.

So I had to do some additional grout removal myself before proceeding to the grout installation.

My first step as part of the planning process was figuring out which grout removal tools to use.  I already owned an electric Dremel rotary tool as well as a RotoZip rotary tool with a circular saw attachment.

In addition I have an electric oscillating multi-tool.

I decided to purchase a hand grout saw and a grout removal tool with a triangular metal piece on the end.

I also bought a grout removal blade for my oscillating multi-tool and a 1/16″ (Dremel #569) and an 1/8″ (Dremel #570) sized grout removal bits for the Dremel.

The grout saw was useful for grinding the old grout out of the joints, but it is a lot of work with your hands.  I wore leather work gloves when I used the grout saw.

The handle with the triangle on the end was not very useful at all for removing the old grout.  It also has a limited depth range due to the triangle and care must be taken not to scrape the tile edges.

I did most of the grout removal up close to the wall using the Dremel rotary tool with the 1/16″ grout removal bit.  I kept it on the lowest speed and used two hands to keep it steady.  The Dremel grout removal bit easily ate right into the old grout.

I would do short bursts of grinding out the old grout and then switch to vacuuming the dust and debris.  I wanted the joints as clean as possible.  I  used the grout saw to even out the rough spots on the old grout after I used the Dremel.

I kept the battery powered portable work lights close on the floor so I could see what was going on.  I also wore a head lamp, but the Duracell portable work lights illuminated the work area well.

There was moisture where the old grout was broken so I waited a week for the shower floor to dry completely before installing the new grout.

After a week passed and the shower floor was dry, I scraped the previously ground down grout joints with a painters tool to remove any remaining debris.  I also used a wire brush to loosen any stuck particles.  Then I vacuumed the entire floor and joints.


I had worked with Laticrete Spectralock Premium Epoxy Grout several years before when I remodeled a bathroom of my own.  I liked the fact that it is maintenance free and no sealing is ever necessary after installation.  The epoxy grout is stain and mold resistant and is very durable.

I saw this question about epoxy grout someone posted on Fine Homebuilding Magazine’s website and thought you might be interested.

I mixed and applied the epoxy grout.  I spent about six manhours prepping, mixing, applying the grout, wiping the excess grout, and doing a complete clean up.

The epoxy grout is a little different to work with than regular grout.  It has less working time and you need to use the wash packets or vinegar in your rinse water to keep the epoxy from gumming up the sponge.

Laticrete Spectralock Pro Premium Epoxy Grout parts A and B and the sanded color part C are what was used on the re-grouted shower floor
Laticrete Spectralock Pro Premium Epoxy Grout parts A and B and the sanded color part C are what was used on the re-grouted shower floor

A grout float made for epoxy grout must be used.  Inside the mini unit plastic bucket kit the manufacturer furnishes gloves, a sponge, instructions, part A and part B epoxy packets, and two cleaning solution packets.  The grout color comes in another separately purchased carton (Part C).

Parts A and B mix together very easily as two liquids.  The part C colored sand that is added for body and color requires a little more effort to mix into the epoxy base.

I did all of the mixing by hand using a margin trowel and did not feel the need for a power tool to do the mixing.  However I only mixed one small pail at a time.  With a larger pail a power mixer would be needed.

The working time for the grout is 80 minutes with a room temperature of 70 degrees Fahrenheit.  Shorter working time if the temperature is warmer.

In addition to what was inside of the epoxy grout kit, I had on hand a bottle of vinegar, goggles, canvas drop cloth, a margin trowel, dust mask, portable work lights, three plastic 5 gallon buckets each with two gallons of water, clean rags, and one large grout sponge of my own.

I also had to buy an epoxy grout float tool for pressing the epoxy grout into the tile joints.  With the latex gloves on, I used my finger to smooth the corners.

The finished product from how I re-grouted a shower floor with Laticrete Spectralock Pro Premium Epoxy Grout
The finished product from how I re-grouted a shower floor with Laticrete Spectralock Pro Premium Epoxy Grout

If you are planning to do a re-grouting job yourself allow enough time to do it right.  Between the handyman and myself the grout removal took about eight manhours.  Not only does the grout have to be loosened from the joint, but the dust and debris have to be removed before new grout can be installed.

If the old grout and floor are wet, wait several days for everything to be completely dry before installing the new grout.

Working in a small confined space on my knees was uncomfortable and sometimes painful.  I had a folded up canvas drop cloth on the shower floor to soften the human to tile contact points.  A furniture pad would have been more comfortable, but difficult to work with since I had to keep moving around to get into the grout joints with the tools and vacuum.

I wore my Skillers pants with the built-in knee pad pockets during the old grout removal and the new grout installation process.  I found that having the knee pads inside of the pants pockets is more comfortable than wearing separate knee pads around the outside of my pants.  I also never have to readjust them during the day, though my pants do require occasional readjusting.

I don’t think Skillers work clothes are sold in North America anymore.  I know they are sold under a different brand name in Europe.  However Amazon does have an assortment of other work pants with built-in knee pads.

The curing time for the Spectralock Pro Premium Epoxy Grout is fourteen days at 70 degrees Fahrenheit.  Shorter cure time if warmer.  For the 2 inch square floor tile 3 feet wide x 5 foot long, 1.5 buckets of grout were used.  Tile thickness was 1/4″ and the grout joints were 3/16″ or slightly less due to slope.

I used two mini units consisting of 0.2 gallon (0.7 liter) part A & B buckets of Spectralock Pro Premium Grout and two 2 pound (.9 kilogram) part C cartons.

When looking at grout removing blades and bits to purchase, be sure to consider the grout joint thickness.  Get a blade that is thinner than the grout joint.  You do not want to be nicking the tile while trying to remove grout.  While shopping in the store for grout removal bits, I found on some of the tool packaging that details such as blade thickness are in very fine print or not available at all.

Click here for Laticrete Spectralock Pro Epoxy Grout installation instructions.

More information about Spectralock on the manufacturer’s website.

Click here to see my other bathroom related blog posts.

During my online search for Dremel accessories I found this unique item worthy of sharing: multi knife for Dremel oscillating multi-tool for cutting asphalt roof shingles and broadloom carpet.