Home Improvement Stack Exchange is a question and answer site for contractors and serious DIYers. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

What prevents Mortar from being compressed when courses of masonry are stacked.

share|improve this question
This is a good question about theory, but I don't see a practical element to it. Are you facing a specific problem, or are you just curious? – Edwin Jun 4 '14 at 6:05
I'd love to see an answer that contains a good animation, or series of images that shows how the grains of sand in the mortar interact. A brief discussion of Non-Newtonian fluids, might also be interesting. Alas, the answer is more likely to be "Hey! How exactly is a rainbow made? How exactly does a sun set? How exactly does a posi-trac rear-end on a Plymouth work? It just does." – Tester101 Jun 4 '14 at 10:34
@Tester101 If Tester101 can't give us a good illustration, who can? – bib Jun 4 '14 at 14:18
@bib Fluid dynamics is not my thing, so I'd be no help here. – Tester101 Jun 4 '14 at 14:21
  1. Mortar is used much thicker than cement and even thicker than thinset.
  2. Time
  3. Bricks aren't that heavy and generally you aren't just stacking one on top of another.

The only time that you would ever have a weight issue is when building a column or post and if you were skilled enough to climb rows so fast that your previous stuff has no time to set. I am not that good so I have never had that issue. It takes me 3-4 minutes just to butter each brick even. I imagine someone who is really good gets a lot of downtime when doing a post or they do a few posts at a time.

Also I imagine that someone asking this question has too much water in their mix.

share|improve this answer
Probably someone really good at posts does dozens of them at a time so they do have time to set before they come back and do another 4-5 courses. – wallyk Jul 4 '14 at 23:52

With bricks, it's unlikely to be an issue.

With concrete blocks, however, the weight of the blocks and the speed that they can be laid can mean that once you get above 4 courses, the mortar can start to squeeze out before it sets, especially in colder weather.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.