Building Inspections
Beam and Joist Span Tables
Built-Up Wood Floor Beams Supporting One Floor in a House
Maximum Spans for Uniformly Distributed Loads
Species and Grade
Douglas Fir #1 & #2
Hem-Fir #1 & #2
Spruce-Pine-Fir #1 & #2
Supported
Joist Length
8
10
12
14
16
8
10
12
14
16
8
10
12
14
16
3-2X8
9-8
8-8
7-11
7-4
6-10
10-1
9-1
8-3
7-8
7-2
10-0
9-4
8-7
7-11
7-5
4-2X8
11-2
10-0
9-1
8-5
7-11
11-7
10-5
9-7
8-10
8-3
11-0
10-3
9-8
9-2
8-7
Built Up Beam Size
3-2X10
4-2X10
11-10
13-8
10-7
12-2
9-8
11-2
8-11
10-4
8-4
9-8
12-5
14-4
11-1
12-9
10-1
11-8
9-4
10-10
8-9
10-1
12-10
14-1
11-6
13-1
10-6
12-1
9-8
11-2
9-1
10-6
3-2X12
13-8
12-3
11-2
10-4
9-8
14-4
12-10
11-9
10-10
10-2
14-11
13-4
12-2
11-3
10-6
4-2X12
15-10
14-2
12-11
11-11
11-2
16-7
14-10
13-7
12-6
11-9
17-2
15-4
14-0
13-0
12-2
Built-Up Wood Floor Beams Supporting Two Floors in a House
Maximum Spans for Uniformly Distributed Loads
Species and Grade
Douglas Fir #1 & #2
Hem-Fir #1 & #2
Spruce-Pine-Fir #1 & #2
Supported
Joist Length
8
10
12
14
16
8
10
12
14
16
8
10
12
14
16
3-2X8
7-3
6-6
5-11
5-6
5-1
7-7
6-9
6-2
5-9
5-4
7-10
7-0
6-5
5-11
5-7
4-2X8
8-4
7-6
6-10
6-4
5-11
8-9
7-10
7-2
6-7
6-2
9-1
8-1
7-5
6-10
6-5
Revised: 2013-Jun-21
G:\DSDSystem\Handouts\Building\Residential\BeamAndJoistSpanTables.docx
Built Up Beam Size
3-2X10
4-2X10
8-10
10-2
7-11
9-2
7-3
8-4
6-8
7-9
6-3
7-3
9-3
10-8
8-3
9-7
7-7
8-9
7-0
8-1
6-7
7-7
9-7
11-1
8-7
9-11
7-10
9-1
7-3
8-5
6-9
7-10
3-2X12
10-3
9-2
8-4
7-9
7-3
10-9
9-7
8-9
8-2
7-6
11-2
10-0
9-1
8-5
7-11
4-2X12
11-10
10-7
9-8
8-11
8-4
12-5
11-1
10-2
9-5
8-9
12-10
11-6
10-6
9-9
9-1
City of Nanaimo Guidelines
Page 1 of 2
Floor Joists – Living Quarters Span Tables
Hem-Fir No. 1 & 2
Subfloor
Thickness
5/8
3/4
A
B
C
D
E
2X8
Joist Spacing
12”
16”
12-2
11-7
13-6
12-10
13-9
12-10
14-2
12-11
13-1
12-4
2X10
Joist Spacing
12”
16”
14-4
13-8
15-10
15-1
15-10
14-10
17-7
16-4
15-3
14-4
2X12
Joist Spacing
12”
16”
16-5
15-7
18-1
17-3
17-10
16-7
19-8
18-4
17-2
16-2
A
B
C
D
E
12-11
14-2
14-2
14-2
14-2
15-3
16-10
17-2
18-2
16-6
17-5
19-3
19-4
21-4
18-7
Installation
12-2
12-11
12-11
12-11
12-11
14-4
15-10
15-10
16-6
15-3
16-5
18-1
17-10
19-8
17-2
Spruce-Pine-Fir No. 1 & 2
Subfloor
Thickness
5/8
3/4
A
B
C
D
E
2X8
Joist Spacing
12”
16”
11-7
11-0
12-10
12-2
13-1
12-2
13-6
12-4
12-5
11-9
2X10
Joist Spacing
12”
16”
13-8
13-0
15-1
14-4
15-1
14-1
16-8
15-7
14-6
13-8
2X12
Joist Spacing
12”
16”
15-7
14-10
17-3
16-5
17-0
15-10
18-9
17-6
16-4
15-5
A
B
C
D
E
12-4
13-6
13-6
13-6
13-6
14-6
16-1
16-4
17-3
15-8
16-7
18-4
18-5
20-4
17-9
Installation
11-7
12-4
12-4
12-4
12-4
13-8
15-1
15-1
15-8
14-6
15-7
17-3
17-0
18-9
16-4
A:
B:
C:
D:
Strapping or Ceiling Finish to Underside of Joists.
Strapping and Glued Subfloor or Ceiling Finish to Underside of Joists and Glued Subfloor.
Bridging and Strapping or Bridging and Ceiling Finish to Underside of Joists.
Bridging and Strapping and Joists Glued to Subfloor or Bridging and Ceiling Finish to
Underside of Joists and Joists Glued to Subfloor.
E: Bridging Only.
Information compiled for your convenience from “The Span Book” Canadian Wood Council 2009 Edition.
For expanded options refer to “The Span Book” 2009 Edition.
Revised: 2013-Jun-21
G:\DSDSystem\Handouts\Building\Residential\BeamAndJoistSpanTables.docx
City of Nanaimo Guidelines
Page 2 of 2