An engineer was looking at my Concrete Unit Masonry spec and questioned a word in a paragraph from an old Masterspec entry, the verbage: “Single-Source Responsibility for Masonry Units: Obtain exposed masonry units of a uniform texture and color, or a uniform blend within the ranges accepted for these characteristics, from one source and by a single manufacturer for each different product required.”
The Engineer suggested I remove the word exposed from the spec section as there was no exposed masonry in the job. Does anyone agree with this engineer? I can’t even begin to estimate how many jobs this paragraph has been used in and the use of the word “exposed” never came up?
I’m not sure the engineer needs to be weighing in on color and texture. I also don’t think you need to dictate color and texture of concealed masonry. If there’s no exposed masonry, maybe consider deleting the entire provision. But deleting “exposed” changes the intent.
This is a spec section I prepared for the Engineer pro bono, the engineer doesn’t provide specs but the bank wants specs, one of those deals, I’ve known the engineer for 20 years so I volunteered to assist.
Variations in color and texture could indicate products with variations in performance characteristics such as strength. Hence, it is can be retained as a quality assurance measure.
The engineer may have been going for “Obtain masonry units from one source and by a single manufacturer for each different product required.”
What is the value of such requirements? Assuming appearance is not a factor, if the products meet the specifications, what does it matter where they came from?
I agree with Sheldon and Liz here.
With Sheldon in that if it is all concealed, single source is essentially irrelevant - if it preforms, who cares what color it is - and there are no issues that I know of where single source for concealed masonry would address.
With Liz because the way this paragraph is worded, a note to the specifier should have stated, “Delete the paragraph below if there is no exposed unpainted masonry or where color control is of no importance.”
William
I only include this language for decorative CMU, not garden variety gray block - even if that garden variety gray block may be exposed in the finished work. Retaining this language for non-decorative CMU is over specifying.
I don’t think color or texture serves as a quality assurance measure for strength - that should be done by the manufacturer via a QC plan. A batch produced with aggregate from an alternative supplier may change color with no change in performance. I think this paragraph is intended solely for exposed, especially unpainted, CMU and can be deleted if not needed. It is arguable whether it is otherwise required to have a sole source clause.