MPNH Floor Extension
Engineering Feasibility
This section of the report presents the structural analysis of a simplified model of the floor extension. The purpose of this section is to illustrate the loads that will be imposed on the main structural members and to raise any areas of concern for the floor extension. The analysis only involves checking the bending strength in the beams and the compression strength in the column. The 3D model of the floor extension structure was drawn using Sketchup.
Since the analysis is done on a simplified model, there are various assumptions that were made. The parameters required for the analysis were acquired from the National Building Code of Canada and the Wood Handbook.
Floor extension components:
Nine 1’ × 1’ Douglas Fir beams:
3 lateral beams of length 11’ 6”
6 longitudinal beams of length 15’ 6”
Forty 2” × 10” Douglas Fir joists:
6 lateral joists of length 11’ 6” --> Lateral1
30 longer joists of length 14’ 2” --> Lateral2
4 longitudinal joists of length 15’ 6”
Total length of joists = 6 × 11’ 6” + 30 × 14’ 2”+ 4 × 15’ 6” = 556 ft = 169.5m
Six 1’ 6” × 1’ 6” Douglas Fir columns: 12 ft per floor
Height of each column = 12 ft/floor × 2 floors = 24 ft
Floor board: 19mm plywood + 10mm engineered hardwood
3 fixed gypsum drywalls: thickness = 20mm
length = 11.5 + 15.5×2 = 41.5 feet = 42 feet = 12.8m, height = 12ft = 3.7m
Total area of wall = 3.7 × 12.8 = 47.4 m2
Please refer to Tables Below
Figure 1: Sketchup drawing of simplified floor extension model
Simplified Model Assumptions and Parameters:
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Rectangular area
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Six existing columns; three on either side
- Equal distance between each column
- Approximate cross section
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Approximate area dimensions
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Considering floor extension, additional walls, existing hallway area, roof area
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Using dead and live loads from building code
- Design dead load of flooring, wall, roof materials
Measured dimensions from conceptual Sketchup drawing:
Length (longitudinal) = 33’ 1 ¼’’, Width (lateral) = 12’ 11’’
Dimensions used in model:
- Floor extension - Length (longitudinal) = 34’, Width (lateral) = 13’
- Hallway – Length = 34’, Width = 6’
- Longitudinal distance between columns and beams (center to center) = 17’
- Lateral distance between beams = 6’ 9”
- Longitudinal distance between joists = 1’
Area of floor of floor extension = 14’ 6” × 35’ 6” – (6 × 1’6” × 1’6”)
= 501.25 ft2 = 46.6 m2
Area of hallway = 6’ × 35’ 6” = 213 ft2 = 19.9 m2
Area of roof = Area of floor extension + Area of hallway = 66.5 m2
*Douglas Fir Columns, beams and joists *Longitudinal Note: Douglas Fir density = 27 lb/ft3 = 4.2 kN/m3
*Douglas Fir Columns, beams and joists *Longitudinal Note: Douglas Fir density = 27 lb/ft3 = 4.2 kN/m3
Details for Walls Roof and Flooring Materials Note: Material Values from NBCC
Details for Walls Roof and Flooring Materials Note: Material Values from NBCC