RESOURCE TERMS OF USE AGREEMENT

Simplified Partition Wall Calculator

This Resource Terms of Use Agreement (“Agreement”) is a legal agreement between Canada Masonry Design Centre (“CMDC”) and you, the individual or entity accessing and using the Resource (“Resource”) known as “Simplified Partition Wall Calculator” ("SPWC”) on the CMDC website: http://www.canadamasonrydesigncentre.com.

The agreement can be read by clicking here (opens in new tab)

Know the Scope of this Tool

Emphasizing the importance of understand the scope and limitations to get the most out of this resource

The partition wall calculator runs simplified structural analysis where the user inputs project specific information. There are additional assumptions required to make a tool like this available, please read the following limitations to make sure you properly apply the results you receive. An Expanded Limitations page which covers each facet of these limitations can be opened in a new tab (you don't lose your progress) by clicking here.

If you have any questions at all, please contact CMDC.

How much can be attached to my partition wall?

Finishings

This simplified partition wall calculator accounts for finishings being placed on one or both sides of the wall. In order for the results to be applicable, The combined weight of all finishings cannot exceed 30kg/m² on any partition wall face. For reference this is about the weight of a 12 mm thick porcelain tile. More detailed information can be found here (opens in new tab).

Fixtures

Cabinets, TV’s, shelving, or other mounted weights can be installed on partition walls designed with this calculator if they meet the following requirements:
• Unreinforced walls can have up to 40 kg hanging off the wall, but the center of the weight is limited to within 0.2 m off the face of the wall.
• Reinforced walls can have up to 150 kg hanging off the wall, but the center of the weight is limited to within 0.5 m off the face of the wall.
• Only 1 fixture is allowed for any given meter of wall length.
• The results of this calculator are not valid if fixtures are connected directly above or below an opening

Supporting the wall without accidentally supporting the structure

Lateral Support

Partition walls considered within this tool are assumed to span vertically, laterally supported along the top and bottom edges. While the reaction at the base might be resolved through dowels, mortar bond, or friction, the top of the partition wall must be supported by lateral support anchors. This tool provides a reaction force per meter of height of wall based on support points (i.e. partition anchors) provided at 1.2 m on center. Supports are also required within 600 mm of each movement joint or end of the wall. An explanation of these requirements is available here (opens in new tab).

Isolation from Primary Structure

Isolating partition walls from the primary structure is important to ensure that partition walls are truly nonloadbearing. This can include a gap along the top of the wall below the slab or roof element, and it can also include a gap along the ends of the wall where it meets a column or loadbearing wall. The size and detail of the gap should be based on an analysis of the structure and will depend on the expected movement of the structure of the building when subjected to the design loads. More information on isolation requirements is available here (opens in new tab).

General Masonry Provisions

Covering some of the broader assumptions and applications regarding materials, construction, and design intentions.

Masonry Units and Mortar

All concrete masonry units must meet the requirements of CSA A165.1, having a minimum compressive strength of 15 MPa and having a minimum density of 1700 kg/m³ (i.e.: Type D units are not permitted as they are beyond the scope of this tool).
The mortar used shall be Type S in conformance with CSA A179. Click for more information (opens in a new tab).

Bonding Pattern

Unreinforced masonry partition walls may be built with stack pattern and/or decorative bonds as long as they are vertically spanning walls and all minimum joint reinforcement requirements of CSA A371 are met.
Reinforced masonry partition walls must be constructed in 50% running bond. This tool is not valid for reinforced walls constructed in stack pattern or other decorative bonds. More information on these requirements can be found here (click to open in new tab)

Horizontally Spanning Walls

The results of this tool can be valid for horizontally spanning, unreinforced masonry walls when lateral support connectors are spaced vertically every 600 mm (as opposed to the 1200mm spacing along the top support for a vertical span).
This tool is not valid for horizontally spanning, reinforced masonry partition walls.
When interpreting final design table, the maximum height may be taken instead as a maximum length, where the anchor load can be divided by 2 to account for the closer spacing lateral supports.
Click for more information on these restrictions (opens in a new tab).

Design Wind Pressure

In the design of interior walls and partitions, careful attention must be paid to differences in air pressure on opposite sides of the wall. The National Building Code of Canada 2015 Structural Commentary (I, 58) suggests an unfactored wind pressure of at least 0.25 kPa or a value of 0.50 kPa in situations where large openings exist in the exterior envelope and there is a potential for exterior wind pressures to be transmitted to interior walls and partitions.
This tool is not intended for the design of exterior walls, which must be designed to resist loads based on the exterior wind pressure in accordance with the National Building Code. Click for more detailed information around wind loading (opens in new tab).

Seismic Hazard Index

The seismic hazard index (I_EF_aS_a(0.2)) is a standardized representation of the anticipated earthquake hazard for a particular site and building. It is defined as the product of the earthquake importance factor (I_E), the site coefficient (F_a), and the 5% damped spectral response acceleration for a natural period of 0.2 seconds (S_a(0.2)). More information on seismic hazard index is available here (opens in new tab).
For the design of masonry partition walls, the seismic hazard index is relevant for calculating the seismic loads and may trigger prescriptive limits at specific thresholds. The seismic hazard index is typically indicated within the structural drawings, geotechnical report, or may determined by a structural engineer. 

Block Size

The maximum height that a partition wall can extend is a function of many different factors. Masonry unit thickness tends to have a large effect on maximum design height as it has a large impact on cross section strength and stiffness. While there have been many different rules-of-thumb used for designing walls by adhering to a limiting height-to-thickness ratio, there area often notable exceptions that can result in potentially unsafe designs.
The maximum height values provided by using this tool are based on engineering analysis in accordance with the CSA S304 design standard and provide a more consistent factor of safety for design when compared to historical empirical rules based on using a limiting height-to-thickness ratio.

Please select a wall thickness option below:

Normal or Leightweight CMU?

Although partition walls are nonloadbearing and do not support weight from the surrounding structure above, density is needed in order to calculate the self-weight of the portion of wall acting above the critical section.

CSA A165.1-14: Table 1 defines units made with varying densities of concrete as follows:

Type A CMUs are made using concrete with a density greater than 2000 kg/m³.
Type B CMUs are made using concrete with a density between 1800 kg/m³ and 2000 kg/m³.
Type C CMUs are made using concrete with a density between 1700 kg/m³ and 1800 kg/m³.
Type D CMUs are not within the scope of this tool (and are not commonly available across Canada).

Types A and C are the most commonly available options across Canada, where Type B results have been included with Type A

Openings and Penetrations

Any interruptions in a partition wall, large or small, will have an impact on the load distribution and can reduce the available cross section. There is an upper threshold of allowable penetrations that has been considered in determining the maximum height, but any openings or penetrations beyond that size must be considered as a “Large Opening” when using this tool.

Allowable Penetrations

Penetrations for piping, electrical or others are permitted within the scope of this tool when all of the following limits are satisfied. Each penetration must not exceed 152 mm (6”) in any direction and the total area of penetrations in any given 1.0 m² of the wall cannot exceed 0.1 m². In addition, these penetrations are not allowed in the central third of the wall height. Click for more information (opens in new tab).

Large Penetrations

It is common to require large openings at the top of partition walls (for example, to accommodate ductwork). In cases of larger penetrations exceeding the "Allowable penetrations" section above, “1.2m opening” must be selected in the “Openings” drop down list. The following conditions must also be met:
• The large penetration is limited to a height of 254 mm (10”) and a length of 410 mm (16”).
• The wall must be constructed using 15cm units or larger.
• Opening cannot interrupt lateral support clips or reinforcing bars.
• Cannot be within 1 m of a window, door, or other large opening, measured along the length of the wall.
Click for more information (opens in a new tab).

Partition Results

Maximum allowable heights, h_max, and lateral support anchor loads, V_f/m, are shown below:

Please review the top 4 rows to ensure they match all intended inputs. The first column lists all possible cross sections by vertical reinforcement pattern. All results correspond to partially grouted masonry, meaning only cells containing reinforcement are grouted and unreinforced walls are hollow.
Questions about how to interpret these results? Click here (open in new tab) for more information, including examples. or contact us.

* non-standard CMU's made with higher % solid to meet a 2 hour FRR using the equivalent thickness compliance pathway per NBCC. These are not available in all geographic regions. % solid_min need not apply for units certified through testing.

h_max is the maximum allowable height in m of the partition. Using this resource for a horizontally spanning partition? Click here to review provisions and support requirements.
V_f/m is the lateral support anchor shear force per m height of constructed wall (not maximum allowable) that the lateral support must resist, in kN (based on partition anchors spaced at 1.2m).
FRR is the Fire Resistance Rating calculated using the NBCC 2015 Annex D Equivalent Thickness Method.
STC is the Sound Transmission Class with values proved by the CCMPA Metric Technical Manual.
% solid is the net volume of the unit divided by its gross volume as defined by NBCC 2015 Annex D, and as reported by the manufacturer.

Notes

• Linear Interpolation is NOT permitted within these tables.
• Design values are based on partially grouted walls constructed using hollow units. Semi-solid units or fully grouting reinforced walls to achieve a higher FRR or STC is permitted, given there is enough space to provide vertical reinforcement
• Use of FRR values are based on a minimum %_solid, to be confirmed with unit manufacturer supplying the project.

Questions about how to interpret these results? Click here (open in new tab) for an explanation, including basic examples.

Still have questions? Contact CMDC for assistance.