Why do you have to lay down tiles with mortar and then put grout
between the tiles?
Why can't you just put mortar between the tiles?
Is grout more waterproof than mortar?
Can you use mortar as a substitute for grout and then put a penetrating
sealant on top of the mortar?
I might be wrong, but I don't think you can put sealant on mortar. The
obvious answers are that
1. Mortar is messy
2. Grout can be colored to people's wants and needs
3. Grout is much more forgiving
4. Grout does not stick to mortar
Mortar is formulated to bond masonry units together. The main
ingredient of mortar is Portland cement. Grout is not mortar and not
concrete either. It is in between like a soft concrete. Grout has a
certain fluidity because it must fill in narrow spaces well. Mortar
does not have the same consistency or fluidity as grout. Plus, grout is
made of finer materials that are similar to mortar, but the makeup of
grout is different. Mortar just doesn't flow the same.
They both have different jobs and they are both made to do their jobs
better than the other. If you want to use second best materials, go ahead,
but don't be surprised if it does not work out as well as you hoped.
Why do you want to avoid grout. Do you think you will save some money?
It will not be much.
Well I had to remove 4 tiles a few inches above the kitchen sink to get
at the pipes behind the faucet. Then I used thinset mortar to put them
back. So it's only 4 tiles and I think they pretty much stay dry all
the time. The reason I don't want to use grout is because it has those
glass particles that can injure your lungs and eyes. The thinset mortar
also has the same glass particles and it was an ordeal going through
the safety precautions to avoid hurting myself.
You are confusing silica with glass. There is a danger from
silica dust if you inhale enough of it. Working with enough
grout for 4 tiles is not going to come close to causing any
damage to you. It is somewhat like asbestos. It is dangerous
to be exposed to it in large quantities or for long periods.
Silica is one of the most common minerals on earth. Wear a
dust mask and don't worry about it.
Are you taking a bag of the stuff dry and throwing it around the
kitchen? Or are you doing what any normal person would do, which is
mix up a pint of thinset or grout outside the house and then just use
it? Used in any reasonable fashion for a simple repair, this stuff is
In a paste, the risks are less. Like someone else said, wear a mask and
don't worry about it. If you are concerned about your eyes, wear
googles. I've done a lot of tile and don't have any silica related
My trash man would not take a partial bag of cement one day. He
explained that the lime caused an eye injury to an employee and it is
now company policy (re-bagged and sent out).
I replaced a couple of tiles in my pool this year at the water line. I
found a small pale of grout/mortar combination (orange store). It is
made for curing under water. I did go ahead and drain water below the
tile as I was not that trusting. This stuff worked well... adhered
well and looks like the same as the rest of the tile grout lines.
You won't find it in color choices, though.
"Well, it doesn't happen all the time, but when it happens, it happens
Frankly I would want to use something as close as possible to the
original grout. You want to match the existing grout as close as possible
and I really don't think they used mortar.
BTW I agree with the others on the safety issue.
Cementitious mortar and grout are both portland cement based, with sand
aggregate for both (in the case of sanded grout).
In a primitive style, they are one and the same.
Today, mortar would typically be made from the cheapest, gray portland
Grout would be made from more costly white portland cement, to yield a
white color or, with tinting, various colors.
Mortar for marble or other light porous stone would be more like the
white grout, to avoid bleeding a gray color into the stone.
There are various additives for accelerating/retarding the set,
plasticity, polymer modification, water repellancy, etc. Some of these
properties are desirable for mortar or grout or both.
But sure, in the olden days, you had one primitive cement and the same
stuff was used for both bedding and grouting.
replying to Richard J Kinch, Handygirl wrote:
Thank you for that! Asked a sales person for a bag of grout had him place it in
the car for me (50lb) bag and never looked at it. Started grouting when I
returned home and never noticed it was mortar. I've been worried that I made a
huge mistake on my backsplash. However, the backsplash is natural stone roughly
cut and I think it looks pretty good. Just wondering ....do I still seal the
mortar. Luckily the stone was sealed previous to grouting so....the big
question....will this work???
The primary difference is that grout has small or no aggregate particles and
is meant for narrow joints, joints from 1/16" to maybe 3/16. Mortar has
larger aggregate - the aggregate makes it strong - so it will be fine for
your joints assuming the joint width is large enough to accommodate it.
And yes, seal it.
replying to dadiOH, Handygirl wrote:
Thanks Dadioh. I noticed that small holes appeared between the stone so I
proceeded to fill in any little cracks or holes. Uhh what a tedious job. It
really looks good though I didn't do it correctly. Next time I'll know. Thanks
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