About Mortar
Mortar and Properties
Mortar is a mixture of portland cement, lime, sand, and water.
The type of mortar on a project is determined by inspecting your original mortar and trying to determine what type was used. Depending on whether we are installing a new build and materials or repairing an existing project we can always use the ASTM C-91 standards for mortar.
Mortar has very complex chemical properties and varies depending upon the project.
Although there are many complex physical properties I will only speak of a couple that matter the most.
* While this data can be challenged it is meant to be only a guide to help understand the mortar being used. Most information was available from ASTM-C-91 standards. Also, the curing process can vary due to many different situations such as temperature, humidity, airflow, etc. Cary Masonry is not held responsible for any inaccurate information and suggests anyone more interested in more information to thoroughly research.
Mortar is a mixture of portland cement, lime, sand, and water.
The type of mortar on a project is determined by inspecting your original mortar and trying to determine what type was used. Depending on whether we are installing a new build and materials or repairing an existing project we can always use the ASTM C-91 standards for mortar.
Mortar has very complex chemical properties and varies depending upon the project.
Although there are many complex physical properties I will only speak of a couple that matter the most.
- *Most all Mortar types will reach 60% of their compressive strength in 1 to 7 days and will be from 500 psi to 1800 psi depending on the type of mortar used.
- *Most all Mortar types will reach 100% its full compressive strength in 28 days and will be from 900 psi to 2900 psi.
* While this data can be challenged it is meant to be only a guide to help understand the mortar being used. Most information was available from ASTM-C-91 standards. Also, the curing process can vary due to many different situations such as temperature, humidity, airflow, etc. Cary Masonry is not held responsible for any inaccurate information and suggests anyone more interested in more information to thoroughly research.
Mortar Color and Matching
Matching mortar color may seem easy but in reality, it is a long tedious process. Experimentations are always happening in our shop and it involves many different materials. We experiment with many different mortars, sands and dyes to try to match the area we are working in which in this case is North Carolina. We have experienced many different colors and shades of mortar in NC and it is challenging and some of the reasons are
We do have a process we do before we start a project that we use (our company secret) to get the color to match as close as possible and varies for each project.
The mortar we repoint will never look like the mortar we are trying to match when it is fresh. It has to cure and it will eventually happen. There is a notable thing to remember and that is the mortar joints on the home or building have aged and been weathered for years in most of them so the fresh mortar is always trying to catch up to the original mortar which is still aging.
On some projects such as brick pointing steps the best thing to do is take all the joints out and put fresh new mortar in them to make it look new and all one again. This can be more costly than standard tuckpointing just the cracks but may be worth it to you and you can get a free estimate by filling out our Quick Quote Form.
Matching mortar color may seem easy but in reality, it is a long tedious process. Experimentations are always happening in our shop and it involves many different materials. We experiment with many different mortars, sands and dyes to try to match the area we are working in which in this case is North Carolina. We have experienced many different colors and shades of mortar in NC and it is challenging and some of the reasons are
- Age of the mortar
- Inconsistent mixes for each batch or mortar made from the mason company
- Weathering form years of rain, freezing, extreme heat ,etc.
- Mold and mildew and other elements such as dirt that permeated deep into the mortar
- Most colors of mortar here in NC come from the color and type of sand the original builder/contractor used on the project.
- The sand can come from many plants and as the years go by the sand and its shades change also.
- There is also many different types of cement and lime that could have been used 10,20,30 years ago or more depending on how old the home or building is and that the shades have changed and different companies came in and went out of business.
- On top of all the variables, there could have been dyes used.
We do have a process we do before we start a project that we use (our company secret) to get the color to match as close as possible and varies for each project.
The mortar we repoint will never look like the mortar we are trying to match when it is fresh. It has to cure and it will eventually happen. There is a notable thing to remember and that is the mortar joints on the home or building have aged and been weathered for years in most of them so the fresh mortar is always trying to catch up to the original mortar which is still aging.
On some projects such as brick pointing steps the best thing to do is take all the joints out and put fresh new mortar in them to make it look new and all one again. This can be more costly than standard tuckpointing just the cracks but may be worth it to you and you can get a free estimate by filling out our Quick Quote Form.
