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Andrew Wilson
04-12-2017, 08:27 AM
Hello all,
I am a masonry contractor, and I wanted to see if someone would point me in a direction on how to assess allowable tolerances for "rolls" in the wall may occur, ie if you stood at the bottom of the wall and looked directly up and the wall fell vertically out of plum but then a few courses up further the wall fell back into vertical plum. forming a kind of "s" or a roll...

I've been seeing a lot of ASTM C216, citing the allowance of the brick manufacture to have brick that are not perfect, but nothing that speaks to the contractors allowable tolerances installing the brick veneer.

I have seen allowable bed joint tolerances @ +/- 1/8" through ACI 530-05 and ASCE 5-05. that would allow me to have a bigger bed joint, where the brick would start to fall out of plumb, but I cant find anything that directly addresses the tolerances of how far the wall may fall vertically out of plumb.

And the last issue I am having, is how do we go about looking at the wall to assess these tolerances... Should we be at walking pace, 20' away from the wall looking at it? Any help on how you look at the wall to assess these standards would be appreciated.

Any help would be appreciated

Claude Lawrenson
04-12-2017, 09:42 AM
Here's one reference guide - checkout part "J-Construction Tolerances".http://www.gobrick.com/portals/25/docs/technical%20notes/tn11c.pdf

1. Maximum variation from plumb in vertical lines and surfaces of columns, walls and arrises:
a. 1/4 in. (6.4 mm) in 10 ft. (3 m).
b. 3/8 in. (9.6 mm) in a story height not to exceed 20 ft. (6 m).
c. 1/2 in. (12.7 mm) in 40 ft. (12 m) or more.

Jerry Peck
04-12-2017, 11:57 AM
Most codes reference ACI 530.

My recollection is 1/2" off plumb line in 10 feet, and 1" off straight line in 20 feet.

ACI 530 is the standard for masonry.

The Brick Association Tech Note seems more restrictive than I recall that code, which is good because it you meet that, then you meet the code.

ROBERT YOUNG
04-13-2017, 03:54 PM
Plumb, is plumb, is plumb!:clap2:

Tolerance in masonry construction.

Brick veneer.
15mm maximum deviation from specified or documented dimension.

Let us assume, god forbid, 0.590551" the height of a wall.

When I was a lineman, and helped setup corners, the wall is plumbed from the highest destination to the brick shelf. 1/3" was tolerable.

10mm per story height.

25 mm on platform construction veneer.

Now I cheated a bit and had to reference this on Guide to Standards and Tolerances PDF. (http://www.vba.vic.gov.au/__data/assets/pdf_file/0019/18127/Guide-to-Standards-and-Tolerances-2007.pdf)

Hope that helps.

ROBERT YOUNG
04-13-2017, 04:05 PM
Hello all,
I am a masonry contractor, and I wanted to see if someone would point me in a direction on how to assess allowable tolerances for "rolls" in the wall may occur, ie if you stood at the bottom of the wall and looked directly up and the wall fell vertically out of plum but then a few courses up further the wall fell back into vertical plum. forming a kind of "s" or a roll...

Should not be any bulging or heaving. Likely the masonry bond loss.
Where the wall bulges, locate the course by doing a course count. Likely around windows or lentils. Parapets lean in or out. Mostly outward.


I've been seeing a lot of ASTM C216, citing the allowance of the brick manufacture to have brick that are not perfect, but nothing that speaks to the contractors allowable tolerances installing the brick veneer.
Link below.


And the last issue I am having, is how do we go about looking at the wall to assess these tolerances... Should we be at walking pace, 20' away from the wall looking at it? Any help on how you look at the wall to assess these standards would be appreciated.

Any help would be appreciated

From the roof I lower the plumb bob.
I use a 50' foot tape measure on the coping to measure areas of concern.
Use grid line pad and make a approximate drawing of the wall.