Mortar Bed for Acrylic Bathtub


  #1  
Old 08-14-08, 10:27 AM
H
Member
Thread Starter
Join Date: Jun 2003
Location: Canada
Posts: 214
Received 1 Vote on 1 Post
Mortar Bed for Acrylic Bathtub

Hi!

We bought a Rona brand acrylic bathtub from Rona (Canada, eh!) and it appears it is made by Aciflex (www.aciflex.com, I think the model is Bahamas / A2-221). The installation manual says that quote "It is recommended that a layer of mortar be applied and covered with 2 mil polyethylene sheet to facilitate leveling". 3 questions:

1. Is this step necessary?
2. If yes, what exact mortar product do I use?
3. Step to apply the mortar?

I contacted the company as well.

Howie
 
  #2  
Old 08-14-08, 03:44 PM
J
Member
Join Date: Oct 2006
Location: Wilmington
Posts: 4,214
Received 0 Votes on 0 Posts
If the manufacturer recommends it, you had better do it, or that tub could be cracking in a few years.

This is not the answer you seek, but when I do a bathroom, I never recommend or purchase anything that requires additional support. That is an indication to me that someone took shortcuts in the manufacture of the product. And if I do not supply/install the additional base material exactly right, I could be the one called to account. Yes, the units I install cost more, but I never get callbacks.
 
  #3  
Old 08-14-08, 06:16 PM
plumbingods's Avatar
Member
Join Date: Apr 2008
Location: Manch-vegas, New Hampshire
Posts: 2,180
Received 0 Votes on 0 Posts
Most companies are going to recommend the mortar bed if they have had any claims against them, If you are installing the tub yourself, It would be worth putting it in. If a plumber is installing it, I would get the mortar for him/her and ask nicely if he wouldn't mind putting some down first. This way IF there ever was a problem, the tub manufacturer cannot say the tub was installed improperly and refuse a warranty claim.
Some tubs are built better than others, Some have spacers under the tub to support the bottom, some don't.

Take a plastic trash bag and lay it on the floor if you are worried about moisture against the wood. Then mix up some mortar, not a lot is needed, place in the center of the tub area and spread outward, keeping the mortar a little higher than the tub bottom. Place some plastic over the mortar as recommended and work tub into place and secure. Try not to stand in the tub too much as you will squish the mortar out, but you will want to step into the tub a little so the bottom is not pushing up from the mortar. Let sit overnight.
 
  #4  
Old 08-14-08, 07:16 PM
H
Member
Thread Starter
Join Date: Jun 2003
Location: Canada
Posts: 214
Received 1 Vote on 1 Post
I saw a type of pre-mixed brick mortar at Home Depot, will this work?

How deep should the mortar bed be? My tub has 1 1/2" from the tub bottom to the bottom of the apron.

I found one forum discussion on this topic and one guy said :
"One of the more intriguing methods I have seen was done with columns and rows of small mounds rather than one big clump in the middle of the tub. That way, each mound can have room to "squish" as the tub is pressed down into place." What do you think?
 

Last edited by Howitzer; 08-14-08 at 07:19 PM. Reason: oops!
  #5  
Old 08-14-08, 07:44 PM
plumbingods's Avatar
Member
Join Date: Apr 2008
Location: Manch-vegas, New Hampshire
Posts: 2,180
Received 0 Votes on 0 Posts
Either way will work. Yes you are looking for a mortar premix. Just add water. Don't make it to soupy.

Put the mortar about 2-2 1/2" then it will squish down once set in place.
 
  #6  
Old 08-14-08, 09:45 PM
H
Member
Thread Starter
Join Date: Jun 2003
Location: Canada
Posts: 214
Received 1 Vote on 1 Post
Originally Posted by plumbingods View Post
Either way will work. Yes you are looking for a mortar premix. Just add water. Don't make it to soupy.

Put the mortar about 2-2 1/2" then it will squish down once set in place.
Around the drain is a square hole (about 10" x 10") in the sub-floor. I plan to put a form in place to prevent mortar from flowing too close to it (and down into the basement!). When I place the tub in the mortar bed, I want to make sure the excess mortar has somewhere to go, so that the tub levels out... any advice?

Rona sells Sandmix: http://www.sakrete.com/products/product.aspx?ID=SandMix

Rona also sells MortarMix: http://www.sakrete.com/products/prod...rAndToppingMix

which would you use, Sandmix or Mortar mix?
 
  #7  
Old 08-14-08, 09:57 PM
plumbingods's Avatar
Member
Join Date: Apr 2008
Location: Manch-vegas, New Hampshire
Posts: 2,180
Received 0 Votes on 0 Posts
You can use either, Mortar mix is smoother, sand mix is pretty smooth and heavier duty. But for what you are doing, either will work.
That is why I don't mix it too soupy, so it does not run down the drain hole.

Try not to over pour the mortar. I usually just put the mortar in about an 18" circle in the center, about an inch higher than the bottom of the tub, and it will squish out to the sides and fill in as it goes. Once the tub is leveled, step into it a little but try not to put all your weight into the middle so you don't force the mortar out and defeating the purpose. Remember, you are only supporting about a 3' x 2" area under the tub.


Originally Posted by Howitzer View Post
Around the drain is a square hole (about 10" x 10") in the sub-floor. I plan to put a form in place to prevent mortar from flowing too close to it (and down into the basement!). When I place the tub in the mortar bed, I want to make sure the excess mortar has somewhere to go, so that the tub levels out... any advice?

Rona sells Sandmix: http://www.sakrete.com/products/product.aspx?ID=SandMix

Rona also sells MortarMix: http://www.sakrete.com/products/prod...rAndToppingMix

which would you use, Sandmix or Mortar mix?
 
  #8  
Old 08-14-08, 10:14 PM
H
Member
Thread Starter
Join Date: Jun 2003
Location: Canada
Posts: 214
Received 1 Vote on 1 Post
Originally Posted by plumbingods View Post
You can use either, Mortar mix is smoother, sand mix is pretty smooth and heavier duty. But for what you are doing, either will work.
That is why I don't mix it too soupy, so it does not run down the drain hole.

Try not to over pour the mortar. I usually just put the mortar in about an 18" circle in the center, about an inch higher than the bottom of the tub, and it will squish out to the sides and fill in as it goes. Once the tub is leveled, step into it a little but try not to put all your weight into the middle so you don't force the mortar out and defeating the purpose. Remember, you are only supporting about a 3' x 2" area under the tub.
Would you recommend putting a plastic trash bag over the poured mix as well before installing the tub into the mix?
 
  #9  
Old 08-15-08, 01:17 AM
plumbingods's Avatar
Member
Join Date: Apr 2008
Location: Manch-vegas, New Hampshire
Posts: 2,180
Received 0 Votes on 0 Posts
Originally Posted by Howitzer View Post
Would you recommend putting a plastic trash bag over the poured mix as well before installing the tub into the mix?
I think you said they recommended putting te plastic over the mortar mix. Maybe that is so the mortar does not bond directly to the tub. Personally, I have never used any plastic, so to each his own.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: