If you are going to do some masonry work around your property, calculating the approximate price for the work done is mandatory. In addition, you need to be able to estimate the number of materials needed. This is typically the major stumbling stone for many homeowners since people have no idea of how this is all supposed to be done correctly.
Luckily, you have this article now! Read on to find out how masonry work should be calculated correctly and how you can estimate the amount of money needed for the work to be done. We will provide you with some general information and explain how calculations should be done. With this information, you will be able to estimate masonry works as a pro!
How to Estimate the Quantities Of Masonry Works
First of all, you should be aware that estimating any kind of masonry work typically consists of two parts. One part is about estimating the number of materials needed, and another part is about estimating the cost. Of course, it is important to realize that all the information given here is approximate, as well as numbers, but at least, you can use it for your specific calculations.
Let’s start with estimating the number of materials used in a typical masonry project. Usually, the number of materials that are going to be used (also referred to as a volume) can range from a relatively simple task to the comparatively difficult one. Depending on whether you need to build a garden wall or restore/build the wall of your house, you will require a distinct amount of mortar, brick, or stone, etc.
This is why large masonry estimating projects often require more detailed and precise computer estimating programs or at least a good knowledge of the project. Such precise estimating is mandatory because these projects typically consist of many construction phases and they are highly complex in layout and detailing. Also, the more precise the calculations of such projects is, the easier it is to achieve a reasonable estimate of the materials required for construction.
However, for smaller masonry projects, or as a general means of obtaining approximate estimates, the rule of thumb methods described in this TEK provides a practical means of determining the number of materials required for a specific masonry construction project.
Below, we also suggest you find out how to estimate some specific materials that are often used for different masonry works. The method of calculation provided is approximate so take that into consideration!
Estimating Concrete Masonry Units
The units themselves is probably the most straightforward material to estimate for most masonry construction projects. In order to determine the number of concrete masonry units required for any project, you can make use of a simple method: just determine the total square footage of each wall and divide by the surface area provided by a single unit specified for the project.
For example, for conventional units having nominal heights of 8 in. (203 mm) and nominal lengths of 16 in. (406 mm), the exposed surface area of a single unit in the wall is 8/9 ft2 (0.083 m2). Including a 5 percent allowance for waste and breakage, translates to 119 units per 100 ft2 (9.29 m2) of wall area.
Since it does not matter how wide the units are, this method of determining the necessary number of concrete masonry units for a given project can be applied to estimating the number of units required regardless of their width.
When using this estimating method, remember that the area of windows, doors, and other wall openings needs to be subtracted from the total wall area to yield the net masonry surface!
Estimating Mortar Materials
Mortar is probably the most commonly misestimated material used for masonry construction. Variables such as mortar proportions, construction conditions, unit tolerances, and work stoppages, combined with numerous other nuances often lead to large deviations in the quantity of mortar required for construction jobs.
As such, masons have developed general rules of thumb for estimating the quantity of mortar. These general recommendations can be considered universal since they can be used for various mortar types. However, we want you to note that the following estimates provided below assume that the concrete masonry units are laid with face shell mortar bedding.
Masonry Cement Mortar
Masonry cement is typically available in bag weights of 70, 75 or 80 lb (31.8, 34.0 and 36.3 kg), although other weights may be available as well. One 70 lb (31.8 kg) bag of masonry cement will generally lay approximately 30 hollow units if face shell bedding is used. For common batching proportions, 1 ton (2,000 lb, 907 kg) of masonry sand is required for every 8 bags of masonry cement. If more than 3 tons (2,721 kg) of sand is used, add ½ ton (454 kg) to account for waste. For smaller sand amounts, simply round up to account for waste. This equates to about 240 concrete masonry units per ton of sand.
Preblended mortar mixes may contain portland cement and lime, masonry cement or mortar cement, and will always include dried masonry sand. Packaged dry, the mortars typically are available in 60 to 80 lb (27.2 to 36.3 kg) bags or in bulk volumes of 2,000 and 3,000 lb (907 and 1,361 kg).
Portland Cement Lime Mortar
One 94 lb (42.6 kg) bag of portland cement, mixed in proportion with sand and lime to yield a lean Type S or rich Type N mortar, will lay approximately 62 hollow units if face shell bedding is used.
This assumes a proportion of one 94 lb (42.6 kg) bag of portland cement to approximately one-half of a 50 lb (22.7 kg) bag of hydrated lime to 4¼ ft3 (0.12 m3) of sand. For ease of measuring in the field, sand volumes are often correlated to an equivalent number of shovels using a cubic foot (0.03 m3) box.
The quantity of grout required for a specific masonry project can vary greatly. It typically depends upon the specific circumstances of the project. The properties and configuration of the units used in construction can have a huge impact as well. For example, units that have concrete with low density will absorb more water from the mix in comparison to the units that have higher density.
Moreover, the method of delivering grout to a masonry wall can result in different amounts of waste. Although the absolute volume of grout waste seen on a large project may be larger than a comparable small project, smaller projects may experience a larger percentage of grout waste.
Now you know how to approximately estimate the amount of building materials required for masonry work. This method can be used for any kind of masonry project, but please take into consideration that all the numbers e gave are approximate! For precise results, you need to go for your particular needs and expectations.
How Do You Estimate Cost Of Masonry Work?
What about financial masonry calculations? Estimating masonry is anyway a big job, no matter how complicated the project is since it includes lots of little jobs. Any masonry work typically includes the use of blocks, bricks, tiles, stone, and clay, as well as other optional materials.
In addition, masonry estimating must also take into consideration the following factors:
- wall reinforcement
It can be quite a difficult job to take all these nuances into consideration. As you know, the construction process may often end up costing more than initially expected, or using more material than it was planned. This is why you should always be prepared that your estimate can be a little over or a little under the initial budget.
Because of this, it makes economic sense to build a 10-percent cushion to your final estimate. And also, it might be a good idea to get ready with the help of the following recommendations.
- Prepare for estimating brick wall masonry. Figure out the length and height of the wall
- Multiply the number of materials that you need per square foot by the net wall areas
- Calculate the gross wall area-based and then deduct any gates or other openings that may be required to get the net wall area figure
- Make a drawing representing the relative square feet figures of the wall surface. It will help you determine the number of bricks that you will need
- Add the number of straight walls, pilasters, and other items that may be needed to complete the wall into your estimate. Add this to the calculated estimate of the number of bricks to be used
- Add in the cost of mortar, cement, and any tools that must be bought in order to make a final estimate of the masonry cost of the building
- Determine net quantities of the materials before you add in allowances for things like broken bricks. Generally, it is best to add a 5-percent cushion for brick and a 15-percent cushion for mortar
Like this, you will be ready for any unexpected and extra expenses that might occur during the building project. When you know more or less precisely how much money you need for your masonry work and what materials (and how much of them) are required, it is easier to do all the calculations and plan your budget.
Now you are more aware of how to calculate both the number of masonry materials and the sum of money required for your construction project. As you can see, all these calculations take quite a lot of time and effort, however, they are worth spending the time! In the end, you will get a precise and clear understanding of what sum of money is needed for your project, as well as what amount of building materials you might need. In addition, with the help of the information given in this article, you will be able to figure out in advance how much extra money and materials you might need since building projects often end up with some additional expenses!