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What is a hot mop?

Hot mopping is a safe and reliable technique used to waterproof flooring, shower panels and tile. By combining hot liquid asphalt with layers of quality-grade felt, it creates an impermeable seal that acts as a barrier to protect against leaks and water damage. 

How should we tile over the hot mop? 

You can expect the hot mop shower pan to reach about 10 inches high on the wall.  The tile backer should be set so that it overlaps the hot mop against the wall and into the shower pan. Most tile setters float another layer of concrete/mortar over the hot mop floor and dam before applying the thinset and tile. Please note that it is very important not to puncture the hot mop below dam level. 

What can I expect in terms of the smell? 

Hot mopping is a smoky process that consists of a distinct “tar” smell. We do try to mitigate the intensity of the smell by using low/no smell asphalts. Once your project is complete, the scent may linger for a few hours depending on a variety of factors including weather, ventilation,etc. 

Will you cover finished areas? 

Our team will arrive with about 100 ft of canvas drop tarps to cover carpeted areas. Due to safety concerts, we do not use our tarps to cover hard surfaces. We recommend that you also ask your contractor to cover any hard surface walkways with the appropriate non slip coverings.

Do I need to water test my shower pan? If so, how? 

In order to avoid deforming the asphalt surface, it’s important to give the shower pan enough time to cool before performing any water tests. For most clients, we recommend waiting at least two hours after the hot mopping is complete. 

It’s important to make sure the drain or drain pipe has a test plug. If not, the water will go down the drain through the weep holes. Test-plugs can be purchased at your local hardware store. 

Can you prepare the framing and plumbing for the hot mop of my shower pan?

Our team specializes solely in hot mopping, so the framing must be complete before we arrive. For additional information, please visit our Site Prep page. If necessary, we can install a standard drain; however, there must be a new 2 inch ABS pipe sticking out of the subfloor. There must also be a 2 inch clearance from the outside edge of the pipe to the subfloor and with no couplings below.

Does your team waterproof shower pans using a method other than hot mopping?

We solely offer hot mopping due to its superior value and proven leakguard protection. 

Are there any drains I should avoid?

Yes. Some discount home improvement stores sell a gray cast-iron drain that slips-on over the drain pipe and has a rubber grommet that has to be compressed against the pipe. These drains have a hard-to-access tightening mechanism for the rubber seal that makes it vulnerable to leaks around the drain pipe. We have to limit our warranty on our work when these drains are installed. For a reasonable price, we can usually replace these drains with a more secure shower drain set that we carry.

If my drain is not level, can your team level it for me? 

Yes, if the gap is less than three inches on the wall backing. For gaps that are greater than three inches, visit your local home improvement store and purchase a tin shingle to nail over the gap. These shingles can usually be found in the roofing section. It’s important to make sure that the sheet of metal is at least 27 gauge. If it comes in a small roll, then it is too thin. 

How do I protect the weep holes after mopping?

You can protect weep holes at the base of the drain by surrounding them with gravel, crushed tile, tile spacers, and/or some sort of mesh. For additional information and detailed pictures, check out our blog article Keep Your Weep Holes Open. 

What else can you waterproof using a hot mop?

Hot mopping can be used to waterproof tile surfaces, as well as flooring exposed to high amounts of water with runoff. Examples include but are not limited to showers, low slope roofs, decks, planter walls, etc. Keep in mind that hot mopping is not an effective method for waterproofing areas with pool water. 

Can you also float the mud/mortar base over the hot mop so we can just set the tile? 

Before we begin the hot mopping process, we must first create a preslope for the shower pan. We do this by dry packing mortar mix to create a slope to the subflange of the drain assembly. It's important to note that the finished shower pan will have the cured asphalt exposed; so, you’ll need to hire tile setting specialists to float the mud base for the tile over the hot mop. 

Our team of trained technicians specialize solely in hot mopping shower pans; so, we unfortunately are unable to set the mud base for your tile. 

We have a leaky pan. Can you just hot mop over the existing tile?

No. In order for our team to provide the highest quality service and warranty, we require that all sites be prepared according to the instructions found on the Services page

What are the customer’s responsibilities?

Customer is responsible for any framing and plumbing preparation prior to the hot mop.
Customer is responsible for disabling fire alarm system before we begin hot mopping.
Customer is responsible for clearing and protecting a pathway that will safely allow our installer to carry material and tools to the work area.
Customer is responsible for alerting other trades of our work in order to avoid conflict.
Customer is responsible for permits and inspections including any water testing which includes plugging the drainpipe and filling with water.
Customer warrants that West Coast Hot Mop is authorized to enter the property and perform the work described above.
The customer agrees to indemnify and hold harmless West Coast Hot Mop and its employees from any and all claims or liabilities arising from any act or work performed at the Property other than the negligent or willful act of West Coast Hot Mop.

What is the Disclaimer?

West Coast Hot Mop is not responsible for any leakage that occurs from another trade working in the shower pan. We guarantee that the hot mop will hold water when plugged and pass city inspection as far as hot-mop work is concerned so long as it is properly prepared to do so by the customer. We can NOT guarantee it will pass inspection after anyone has set foot in the hot mop. West Coast Hot Mop offers no other warranties, express or implied, beyond holding water at the time of completion of work and passing inspection as set forth above.

each occurrence
damage to rented premises (Ea occurence)
med exp (Any one person)
personal & adv injury
general aggregate
products - comp/op agg

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