New Shower: Question about sloped mortar bed

[Russell in Georgia]

I am doing my first shower. I have been getting as much advice as possible. The house is on a concrete slab and I plan to use the Kerdi system. I am ready to put in the sloped mortar bed. I have read in several places that this should be constructed of sand and portland cement at a near 5 to 1 ratio. I have also read that you don't want to use mason's mortar because it has lime in it. I have plenty of Quikrete mortar mix available (green label in 60 lb bags). I would like to know if this is suitable or not. It says it contains portland cement and sand, but I can't find the ratio and whether or not it has any lime in it. Why should lime not be included? Just curious. I understand how to mix dry pack mortar and feel like this product will work. By reading some of the other threads, I think I should add some sand, but I figured it would be best to run it by this group first.

Thank you for any comments and suggestions.

Russell in Georgia

[Davy]

Hi Russell, welcome. Mortar mix has sand and masonry cement in it. The masonry has lime in it. That makes it sticky and good for masons doing stone and brick work. Sand mix has sand and portland cement, that's what you want. It usually comes about 3 sand to 1 portland, so you need to add sand or you can use all purpose sand and portland, measure it in buckets 5 to1.

[Russell in Georgia]

Would it hurt to use the mortar mix and add sand to the correct ratio, or will the lime cause any trouble?

Russell

[bathroomremodeler]

Russell,

Skip the use of mortar mix. Instead, use the sand mix + additional sand. Or buy pure portland cement + sand and mix to a ratio of 1 part portland and 5 parts sand.

[Davy]

Russell, the lime makes it sticky and hard to work with, go with the sand and portland cement.