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Shorty10r
Jul 3, 2009, 08:54 PM
I removed a shower pan base and drain but the threaded base is still in line with the sub floor. I have tried to twist this off but it will not move. I am wanting to lay tile in the base of the shower so I bought a shower pan drain for this.. The problem is that the existing plumbing has a screw in base. Do I cut the sub floor out and cut the PVC piping or is there another way to get this off?

Milo Dolezal
Jul 3, 2009, 11:33 PM
You should be able to unscrew it. Sure, it won't go easily, but it will go. Keep trying. Be patient...

If it doesn't go, than cut square hole around the drain, cut riser below the floor and then install new drain.

What kind of shower pay are you planning on doing ?

speedball1
Jul 4, 2009, 04:08 AM
Is this the drain that's giving you a problem?

Shorty10r
Jul 4, 2009, 11:20 AM
Looks kind of similar but it doesn't have the screws on the top. The one I am replacing it with does. I couldn't get it unscrewed so I ended up cutting the PVC... hope this is OK! Just got a coupling and more 2" PVC straight tube. Is there a way to test this before I lay the liner and mortar?

massplumber2008
Jul 4, 2009, 11:31 AM
Hey Shorty:

If you prime and cement the PVC then the 2 or 3 joints you are putting together will not need to be tested... ;)

The shower pan, on the other hand will need to be tested properly, for sure!

First thing to do is to prepitch your membrane by installing about an inch of the mortar you will be using to make your shower pan and pitching that to about 1/4" at drain. Once the mortar dries you will lay down some tar paper and then install your liner and drain.

After the liner is installed wait overnight before plugging the drain (use a test ball... see image, or a plastic bag with socks in it) and testing the pan by filling it with water to the threshold level for 24 hours.

After this period, if no leaks present, then you can pour the shower floor as needed. Be sure to use plenty of small rocks at the PVC membrane drain to insure that the WEEP HOLES in the drain don't clog.

LAstly, be sure that your chicken wire is long enough to install into the shower floor and over the threshold. DO NOT do what the guy at the link provided did. Otherwise, his link is a good one.

Here is a link that may help you understand how to do a better job:

How to Build a Shower Pan (http://www.hoagy.org/house/HowToBuildShowerPan.html)

Let me know if you have more questions...

MARK

Shorty10r
Jul 4, 2009, 02:02 PM
I was reading in a do it yourself book to do the following:
1st build your walls, 2nd lay down vinyl and then screw on middle section of drain, 3rd put on wire, 4th mortar, test for 24 hours, apply thin set, tile

What are weep holes?

massplumber2008
Jul 4, 2009, 02:24 PM
Weep holes are holes in the drain assembly that allow water caught in the shower pan liner to drain by gravity toward the drain. If the membrane is not PREPITCHED then the weep holes are usless anyway.

Prepitch the membrane!

If you pop back later we also have a couple tile/shower specialists here... I am sure they will provide even better information... ;)

MARK

Shorty10r
Jul 4, 2009, 02:55 PM
I see... understand now! Thanks so much will let you know if I have anymore questions... When I put up the mold resistant hardibacker I do this after I mortar not before correct?

Shorty10r
Jul 4, 2009, 03:02 PM
Actually I bought green drywall, is it OK to tile on this

massplumber2008
Jul 4, 2009, 04:26 PM
If you are doing a custom shower you want to install a VAPOR BARRIER and then INSTALL 1/2" HARDIBACKER CEMENT BOARD with alkali-resistant mesh tape and screws.

Do NOT install green board at the shower. If there is any failure in the tile system the green board will quickly WICK the moisture up and into the green board creating mold and will quickly break down with a poor result!

Install cement board only... ;)

MARK

Bljack
Jul 4, 2009, 05:29 PM
I was reading in a do it yourself book to do the following:
1st build your walls, 2nd lay down vinyl and then screw on middle section of drain, 3rd put on wire, 4th mortar, test for 24 hours, apply thin set, tile

:eek: :eek: :eek:

QUICK!!! THROW THAT BOOK AWAY AND FORGET EVERYTHING YOU'VE READ IN IT!!!

Off to fireworks but I promise to reply again later tonight or tomorrow morning.


What are weep holes?
Weep holes are little holes in the clamping ring collar that allow all the water in the setting mortar bed to go down the drain, allowing the setting bed to dry out after usage.

Shorty10r
Jul 5, 2009, 12:25 PM
Lol... I ended up doing tar paper, wire mesh, sand cement to create the base slope, vinyl is getting installed now and will do the 24 hour leak test. After that add more wire mesh and mortar at an angle towards the drain.

massplumber2008
Jul 5, 2009, 12:29 PM
Make sure to put tar paper between the presloped cement and the new vinyl membrane to reduce chaffing/breakdown between the two materials.

After the pan is set, install a vapor barrier and cement board. Be sure NOT to put any screws anywhere in the system below the threshold.

BLJACK will have some more input here so pop back soon!

MARK

Bljack
Jul 5, 2009, 02:11 PM
lol...after that add more wire mesh and mortar at an angle towards the drain.


IF your sloped bed was done correctly, the setting bed will not be formed with a slope, but will be sloped only because it follows the slope below it... understand? The perimeter of the presloped bed should be at the same level all the way around and the furthest point from the drain will be 1/4" per foot, all other areas will have a greater slope as their distance to the drain is less.

You want no lath in the setting bed with one exception that I will cover later, so therefor, there is no need for any tar paper on top of the pvc or cpe liner.

I don't know the mud recipe you used for your preslope, and as long as it woked, it doesn't really matter. For your setting bed, though, you want a mud that is both very packable to create a dense base, very porous, to allow for quick draining, and very easy to shape and screed, so you can form it to be smooth.

Mud recipe 4-5 parts sand to 1 part portland cement. Bagged "sand topping mix" is 3 parts sand to 1 part portland so if you use that, mixing one scoop of sand into the mixing trough with every 4 scoops of sand mix will give you the mixture you want. Use only enough water to give it the consistancy of sand castle sand so you can pack it tight. You don;t want to be able to pour it and you don't want any concrete products as they contain lime, making them stickier and messy to shape.

Your liner needs to go up the walls no less than 3" higher than the finished height of the curb. There can be no fasteners lower than 2" higher than the finished height of the curb. If you take a file or chisel, you should notch the studs along the bottom 6-8" as you don't want the cement board bowing out from the liner or causing abrasive wear over time. Yeah, it's back tracking, but not much at this stage of your progress. Otherwise, you could furr out our walls where the cement board will go. If you do that, hardi is slightly less than 1/2" so furred walls + hardi works out really well without problems joining connecting wall areas as the bull nose tile can bridge it with a small enough joint on the underside of the tile to look nice.

If you haven't already, there should have been blocking installed between the studs to help support the liner where it turns up the walls. Line the walls with a moisture barrier of either 15 lb roofing felt (since you probably have plenty left over) or 4 mil plastic sheeting overlapping lower courses and the liner by 3". Install your cement board, keeping it off the bottom of the liner by about 1/2". IF you furred out your walls, it's not a bad idea to mix up a bit of thinset and comb some ontot he back of the cement board at the bottom just to make sure there is no hollow behind it. When you fasten your cbu, do not fasten along the bottom. When you install your setting bed of mud, it will pin the cbu to the framing taking the place of the fasteners.

For your curb (and the liner completely wraps over it to the outside and down), using left over lath, bend it into the shape of a "U" and bend the sides inward so that it pinches the curb. Fasten it only to the outside of the curb. Just like the walls, the setting bed of mud will pin the inside section of lath to the curb. Your curb is formed out of mason's mix, once it starts to set up, you can shave it to just the right size ans shape. Remember to slope it towards the inside of the shower. As a cheat, don't do the top. Tile the inside of the curb, then the outside, then use the top of the tile from both sides as a screed guide to fill in the top of the curb with concrete.

VERY IMPORTANT QUESTIONS

1) Do you understand everything I wrote above? I'll be happy to elaborate on anything above.

2) Do you plan a bench or recessed soap dish/niche in the walls?

3) Have you purchased any setting materials yet and if so, which ones?

Bljack
Jul 13, 2009, 12:54 PM
Hey Shorty, I've been wondering how your shower is coming along.

Well? :)