What components make a Hot Mop Shower Pan?
Had you ever wondered what’s under the tile in your shower? There are several stages that have to be done in order to have a properly done shower that doesn’t leak!
Here is a picture of a Hot Mop Shower that I did for a clients Showroom. We broke it down in stages to show the process of what involved to getting your walk in Shower completed.
1: First step is to put a pre slope under the hot mop and on top of the sub floor. This is to prevent standing water sitting underneath the tile when the hot mopping is complete.
2: Second step is the hot mopping of asphalt paper in 3 different layers with hot tar in between each layer. This is applied over the cement pre-slope for a 1/4″ per foot slope.
3: This is the stage where the tile contractor performs his magic in prepping for the tile. As you can see the cement bed over the hot mop is in preparation for the floor tiles. At this time the walls are floated and smoothed out with cement for the wall tiles.
4. Last stage is your thinset and tile the part that you see!!
Whats next after the hot mopping is done?
After the hot mop shower pan has been installed, its time to prepare for tile. The 3 most common practices over a hot mopped pan are Cement Board, Hardi Backer or a mud floated shower pan. A lathing paper overlapping into the hot mop at least 4″ minimum starting from the bottom working your way up ensures the path of water to flow into the hot mop shower pan. This makes a barrier keeping water away from your wood studs. Next would be a backer board, thinset and tile or wire lathe scratch coat, mud float, thinset and tile. Your material should be left up 2″ from the hot mop floor to prevent wicking of water up the walls and no nails in the hot mop shower pan below the shower curb/dam to prevent leaks. Very important
How should I protect my hot mop pan?
After the hot mop there is a possibility of other trades coming in to complete work, this can be anything from installing lights, electrical, drywall, etc. The best way to protect the shower pan would be to lay some cardboard down or ram board over the hot mop. This will give some extra protection. It takes a lot to damage a hot mop since the top coating layer is for protection and unless the felt paper is penetrated its ok to have scratches an nicks.
How do you get the hot mop buckect to the shower pan?
There is no better way to get a bucket of hot asphalt to the shower pan than carrying it right through the house. Most hot mopping projects will take an average of 1-2 buckets of tar for an average size shower pan. If you have an appointment set up you can prepare for us by laying down some runners to protect soft surfaces like carpet. Small streaks of tar can be easily removed off hard surfaces with a citrus cleaner.
We screwed holes into the hot mop below the curb. Do we need to replace the shower pan?
No holes or penetrations should be below the curb height. Shower pans when hot mopped are designed to hold water to the height of the dam, before water over flows. Absolutely do not try and screw backer board or wire lathe below the height of the shower pan curb, this will void the hot mop and need to be repaired. If you notice punctures you will have to call us back out to repair your hot mop.
Do I need to be home while the hot mop is being completed?
We understand that everyone can be busy at times. While hot mopping a shower pan can take only 1 hour in some cases, we have other appointments and driving time. Our scheduling allows for a 2 hour window for our hot mop installer to arrive. You can arrange for a way for us to get in your home and we will take care of the hot mopping without you having to be there. If you’re more comfortable you are welcome to arrange to be there while the hot mop shower pan is to completed.
There is a hole in the floor that needs to be filled before the hot mop. Can you do that?
When converting a bathtub to a walk in shower pan you will notice a tub box in the shower pan floor where the pre existing drain was installed. Its common when changing over to a proper hot mop drain that the box will need to be back filled. We recommended filling this hole with sand, pea gravel, or cement to the bottom of the hot mop drain flange and compacted till its firm. We will add our own cement for a pre slope, so if its not perfect we can fix it and build it up properly. There is an extra charge for any extra bags of cement we use to fill any holes. We will do what we can to get your hot mop shower pan completed.
Can I use a pre existing drain if my shower was hot mopped before?
Yes, if you are able to remove the drain top and clean the pervious hot mop from between the flanges we can use an existing drain. We recommended on doing this immediately after demo because with rust some drains will have the clamping bolts so corroded that they will simply break off in the drain while trying to loosen. At this point the whole drain will need to be replaced and a new hot mop drain will need to be installed.
I cant get blocking between the studs beacause a pipe is in the way. Can the hot mop still be done?
Yes. The blocking is for strength purposes. The more blocking a shower pan has, the stronger the hot mop will be. Some shower pans have vent pipes or copper pipes running vertical up the walls between the studs making it difficult to install a 2×10 block between the stud. In this case you can use a thin sheet metal nailed to the outside of the studs to cover the gap. If the gap is less than 4″ we can use our felt paper to correct the issue.
The hot mop is done and I noticed the drain top isn't level.
Drain tops are put back on the same way they were taken off before the hot mop was completed. We will install 3 even layers of tar and paper between the hot mopping, cut a hole for water, to drain then reinstall the drain top. If your drain is not installed level it will be put back on the way it was installed. If you notice this before the hot mopping g is complete ask our installers if there is anything they can do. In some cases we can make minor adjustments if reminded, but we do not take the responsibility of an unleveled drain that was not installed by our team.
I don't want a curb to enter the shower pan. How do i prepare for the hot mop?
It’s not as easy as it sounds. There is a procedure when designing a no threshold shower pan. You can refer to our forum pages where we talk about curbless shower pans and how to hot mop and prepare to achieve the right results.
Can I tile right to the hot mop?
No, the hot mop will need to have a mud bed to bring up the floor to the finished drain height. This will allow you to perfect a nice finished slope according to your specific tile or stone thickness. The curb will need to be wrapped with wire lathe using no nails on the inside of the hot mop, pre bend it to hug the curb and scratch coat cement to prepare for tile. Learn more or get involed in our hot mop shower pans forum for any tips after the hot mop!
Who is responsible for water testing a hot mop shower pan.
We do not put water. The hot mop will need at least 1-2 hours of cool down time after the shower pan is completed. Its best to let the hot mop cool down naturally. Putting cold water on hot tar can change its properties and cause cracking, warping. Some hot mop drains will come with a pre installed plug for water test, plumbers can install knockout plugs when installing the drain in the shower pan, or you can purchase a test plug at your local hardware store for a few bucks. Install the plug below the weep holes down into the drain so water won’t flow down the drain trap. Fill the shower up with water and let sit for 24 hours or overnight.
What are weep holes?
Hot mop shower pans are the last barrier of protection beneath your tile. When your grout cracks or water saturates underneath into the mud bed, water will flow onto the hot mop pan and flow down the pre slope into the weep holes. Weep holes are simply a secondary drain system around the drain flange that allows trapped water to enter the drain system. Before installing a mud bed over the hot mop, you can put a layer of pebbles around the weep holes to protect the weep holes from being clogged with cement. You never want your weep holes plugged in a hot mop shower pan. This can allow water to be trapped between the hot mop and tile.
Can you hot mop over my old hot mop shower pan?
We always prefer to hot mop any new shower pan with a clean area. If the conditions are right we can go over an existing hot mop, but it will be a good idea to consult with us or send pictures so we can see the condition of the previous hot mop.
How long before the smell of hot mop goes away?
The smell of hot mopping and how long the odor last after the hot mop shower pan has been completed is determined by ventilation, natural breezes and the amount of windows. If you have fans available you can assist in speeding up the process. Open windows, get cross breezes, or get positive pressure in a house by closing all windows except for the closest one to where the hot mopping is being performed and force outside air with a fan into the home. The odor usually last a few hours and will go away soon after the hot mop.
What areas do you service in the hot mop industry?
We currently serve Los Angeles, Orange County, San Diego, Riverside and San Bernardino. We have a crew of well trained hot mop installers and we service all these areas daily. We take pride in hot mopping shower pans and have an office staff to take care of scheduling needs and also to answer any questions that you may have. No matter where you are we will be there for you.