Cold Weather Masonry

Q: What are the minimum temperatures in which one can lay brick masonry?

A: With proper protection, masonry can be installed in virtually any weather condition, but there are a couple of key things to remember.

First, codes, specifications and standards provide for protection of the masonry and the masons. The Masonry Standards Joint Committee Code and Specification (MSJC), Section 1.8C on cold weather lists the goals as assuring proper mortar curing and proper bonding of mortar and masonry units. Even if a cold weather construction plan is not required in the spec’s submittals section, the code requirements are mandatory.

Second, mortar temperature must be kept between 40o and 120o F, and the units above 20o F. Units with ice or snow must not be laid.

A third requirement is covering unfinished work at the end of the day (and not just in cold weather).

A note on additives: Use of additives that could affect curing time requires prior approval. Some additives can be highly corrosive.

Resource: www.imiweb.org – International Masonry Institute