19. Glu-lam Alternate Methods Letter.pdfSALUS
HEALTHCARE ARCHITECTURE
June 18, 2018
Leif Bjorback
Linda Thomquist
City of Edmonds, Development Services Department
121 5th Ave N
Edmonds, WA 98020
Subject: Edmonds Recovery Center - Northpoint Recovery
Remodel of Edmonds Facility - 7416 212th Street SW
Alternate Methods for providing glu-lam fire rating - Letter of Rationale
Permit # BLD2018-0447
Dear Leif
This letter concerns Beck & Associates Northpoint Recovery comment #1 9a:
"Provide documentation that demonstrates that all of the glulam beams
maintain a 1-hour rating, consistent with the floor -ceiling assembly rating. ff
this cannot be provided, an alternate means ofproviding the 1-hour rating
at the glulam beams is required to be provided"
The Code Issue:
Since there does not appear to be a rated listing for gludams we cannot met the code
prescriptively, we are submitting an "alternate method of construction (I BC 104.11)"
for your review.
Code requirements for Floor Assemblies in a Type VB.
This building is a VB fully sprinklered. The Occupancy is 1-1 Condition-2
IBC Section 420.3 Horizontal Separation "floor assemblies separating sleeping units
from other occupancies contiguous to them shall be constructed as horizontal
assemblies in accordance with Section 711.
IBC Section 711.2 Horizontal Assemblies shall comply with Sections 711.2.1 through
711.2.6.
IBC Section 711.2.3 Supporting Construction shall be protected to afford the
required fire-resistant rating of the horizontal assembly support.
Exception (to 711.2.3) in buildings of VB construction the construction supporting the
horizontal assembly is not is not required to be fire -resistance rated at the following:
Exemption#2 - Horizontal assemblies at the separation at the separation of sleeping
units as required by Section 420.3.
Code Requirement (711.2.3)for floor rating: This part of the code appears to allow a
non -rated floor assemblv.
1402 Third Ave, Suite 200 / Seattle, WA 98101 / T 206.652.0722 / F 206.340.2266 / wwwsalus.arclhi
Mr. Leif Bjorback
J u ne 18, 2018
Page 2
Code requirements for Floor Assemblies with smoke and fire partitions
The IBC requires both 1 -hour smoke barriers (Section 709) and fire partitions (Section
708) in this project.
In Sections 708.4 Continuity: "fire partitions shall extend to the underside of the fire
resistance -rated floor or roof assembly".
In Sections 709.4 Continuity: "smoke partitions shall extend to the underside of the
fire resistance -rated floor or roof assembly".
Code Requirement (708.4 and 709.4) for floor rating: This part of the code appears to
require a rated horizontal assembl .
Glu-lam Fire Resistance:
We looked at what sort of fire resistance the gludams have:
- To determine strength of the glulam after charring has occurred, we used the APA
Engineered Wood Association Technical Manual: "Calculating Fire Resistance of
Glulam Beams - EWS Y24513". (APA is located in Tacoma WA. Phone: #253-565-
6600)
- Per the Technical Manual, the char -rate thru the glulam is at 1/40" per minute or
1.5" of glu-lam per 60 minutes.
- Per the Technical Manual, the char -rate thru the glulam is at 1/40" per minute or
.75" of glu-lam per 30 minutes.
Glujams that support the second floor:
The gludams that support the second floor are 63/4" wide x 31 " high. However, only
the lower 17" of the glu-lam are exposed because the adjacent 1 -hour rated floor
assembly (see attached detail SD2.01) covers the rest of the gludam.
Grea Lee of ABKJ Structural Enaineers (See attached letter dated 6-18-2018)
evaluated the exposed 17" of this glu-lam and found that the 2nd floor glu-lam can
handle 30 minutes of charring and still support unfactored (service level) loads at the
factored or ultimate stress levels.
Since there isn't a UL listed method to provide a rated enclosure for the additional 30
or 60 minutes of coverage, we propose three alternate method options:
Brian Perry (Product Engineer for Albi Protective Coatings) attached letter
(6/15/2018) states: "Based on the technical Note #EWS Y2445B from the APA —
Engineered Wood Association, the fire resistance rating up to 1 -hour can be
calculated for glu-lam members. This method is recognized by the International
Building Code. Based on the calculations, the 6 3/3" x 31 " glu-lam has a fire
resistance rating of 58 minutes and the 5.5" x 27" glu-lam has a fire resistance rating
of 53 minutes. These calculations were made assuming the beams would be carrying
100% of their maximum design load.
Mr. Leif Bjorback
J u ne 18, 2018
Page 3
Glu-lam Fire Resistance Conclusion:
Based on Greg Lee and Brian Perry's letters, it appears the exposed glu-lams will not
be able to provide a 1 -hour fire resistance. However, the glu-lams will provide at least
30 minute or greater resistance. The following are (3) Options for an "alternate
method of construction (IBC 104.11)" to comply with the intent of the provisions of
the code.
Of the three Options below, Salus prefers Option #1 for ease of assembly and as it is
the least expensive.
OPTION#1 (see attached detail) - Provide (2) layers of 5/8" Type-X GWB on 1/2" metal
clips on the three exposed sides of the gludam. This assembly matches the one -hour
rated ceiling assembly (UL L570) shown on Detail 7/A9.01 which is located on either
side of the gludam. (See attached Detail SD2.02)
OPTION #1 Rationale: If a fire (in a fully sprinklered building) can penetrate (2) layers
of GWB enclosing the gludam, it would also be able to penetrate the (2) layers of GWB
in the rated floor assembly on either side of the gludam.
If (2) layers of rated GW13 are sufficient for the 1 -hour ceiling assembly, then (2) layers
of rated GWB and the 30 minutes of fire resistance provided by the gludarn should be
sufficient to provide the lower 17" of gludam with at least 60 minutes of protection.
Sealant where glu-lam meets the horizontal GWB assembly:
Spec seal-SSS or LCI Sealant sealant will be installed. (See attached "engineered
Judgement Firestop Detail" NS14918024)
This sealant can also be applied when the glu-lam is enclosed with rated GWB.
OPTION#2:
Provide 1 -hour shaft wall (UL Des U469) on the on the three exposed sides of the glu-
lam. (See attached detail SD2.03)
OPTION #2 Rationale: Rated shaft wall is used thru-out this country to provide fire
rated protection and should be more than sufficient to provide 60 minutes of fire
resistance for the glu-lams.
OPTION#3: Provide 40 mils WFT (28 mils DFT) of Albi Clad FT of intumescent paint
over the exposed sides on the three exposed sides of the gludam. (See attached
Detail SD 2.04).
OPTION #3 Rationale:
- See attached Albi Brochure for basic product information.
- See attached letter (dated 6/15/2018) from Brian Perry (Product Engineer for Albi-
Protective Coatings) which states:
Mr. Leif 13jorback
J u ne 18, 2018
Page 4
Albi would recommend applying 40 mils WFT (28 mils DFT) of Albi Clad FP to protect the exposed glulam beams
and deck in place of using gypsum to provide a 1-hour fire resistance rating, This judgement is based on Western Fire
Center Inc, Report # 04042(a), where 40 mils WFT of Albi Clad FP is specified for a 1 hour rating on an open wood floor
joist assembly featuring 2"x10" joists and a deck of TG subfloor and CDX plywood.
Based on the Technical Note #EWS Y245B from the APA - Engineered Wood Association, the fire resistance
rating up to 1 hour can be calculated for glulam members. This method is recognized by the International Building
Code. Based on the calculations, the 6"x3l" beam has a fire resistance rating of 58 minutes and the 5.5"x27" beam has
a fire resistance rating of 53 minutes. These calculations were made assuming the beams would be carrying 100% of
their maximum design load. Based on this, 40 mils WFT of Albi Clad FP applied to the exposed glulam beams will provide
the extra time necessary to achieve a 1 hour rating, Please note that Albi does not have any direct test data for Albi
Clad FP over glulam beams and this judgement is based on an established calculation method and indirect test data.
Option #3 Conclusion: Combining 40 mils of intumescent paint with the at least 30
minutes of fire resistance provided by the glu-lam should be more than sufficient to
provide 60 minutes of fire resistance.
Please review these three options and let us know if you have any questions.
Thank you for your consideration.
Douglas McNutt Principal
1402 Third Avenue, Suite 200
Seattle WA 98101
Cell: 206 605-5597
Direct: 206 957-1906
Office: 206 652-0722
Fax: 206 652-0720
Email: douglas.mcnuttasalus.archi
Web: www.salus.archi
0o, SALUS
HEALTHCARE ARCHITECTURE
Encl: Details SD2.01, SD2.02, SD2.04, SD2.04, STI-Engineered Judgement, Calculating
Fire Resistance for Gludams, Greg Lee Letter, Brian Perry-Albi Letter, Albi Fire proofing
Brochure
C: R. David Frum, FAIA, ACHA
Z:\16029 Northpoint Recovery\Docs\06.01-Municipa]Review\Permit Responses\Altemate Methods Letter\Northpoint -Alternate Methods letter 6-18-2018.doex
02 Third Ave.
fj ISALUS s14-ite 200
Seattle, Wa
01 ARCHITECTURL 98101
(206)652-0722
JOB #: 16029
NEW 1 1/2" THICK CEMENTITIOUS
TOPPINGS OVER 5/8" PLYWOOD
EXISTING GLULAM
EXISTING TJ1
7/8" RESILIENT CHANNELS
PROVIDE 2 LAYERS OF 5/8"
TYPE X GWB AT UNDERSIDE OF
EXISTING I JOISTS
FIRE/SMOKE SEALANT AT BOTH
SIDES COMPLYING WITH UL 2079
EXPOSE ALL SIDES OF GLULAM
SECTION
EDMONDS RECOVERY CENTER
NORTHPOINT RECOVERY
RATED CEILING AT GLULAM
SD2.01
DATE: 06/18/18
REV TYPE: Author
Calculating, Fire Resistance
of Glulam Beams and Colu--
/fAg_ e4rwl- typa-,
Number EWS Y215_B r-Or et�+irv_ IC.-Pa�r
Deceinber 2009 4ftek-eme_r,4 ;7V
INTRODUCTION
r e_fy,,�-4, _S ex- tP%-e_
fm d 0 F= n #5 / e-ff e,�
Glulam beams and columns provide architectural warmth and beauty along with structural strength and natural
fire resistance. In the presence of fire, the outer portion of a glulam member becomes charred. This layer of charred
wood then functions as an insulator, helping to protect the undamaged interior of the member from the heat. The
rate of advancement of this insulating char layer into the remaining, undamaged portion of the mernber has been
well documented (approximately 0.025 inches [0.6 minj per minute) and forms the theoretical basis o t e equations
used to predict fire endurance.' Full-scale fire tests--o—n-Fo—acTea-Fearns --and columns' have confirmed the validity of
the equations in predicting their load -carrying capability under fire conditions and the method is recognized by the
International Building Code (IBC).
19 4A U-3 Z M JI I A d : r-13 -T-1 Ir-11-YA
Calculation of the ability of a glulam beam or column to resist fire for up to one hour is described in the 2009
International Building Code (IBC), Section 721.6. The equations apply to members With fire on three or four sides.
Beams:
Fire on 3 sides
t = 2.54ZB14 - 1�1 .............. (1)
D
Fire on 4 sides
t = 2.54ZB14 - 2BI
............ (2)
Columns:
Fire on 3 sides
t = 2.54ZB 3 - B
1 2DI
............. (3)
Fire on 4 sides
t = 2.54ZB 3 -1 .............. (4)
1 DI
Where:
t = fire resistance in minutes
Z = partial load compensation factor (see Figure 3) which is a function of applied load to design capacity
B = the breadth or width of a beam or the smaller dimension of a column (in.) (see Figure 1)
D = the depth of a beam or the larger dimension of a column (in.) (see Figure 1)
(1) Lie, T. T., 1977. A method for assessing the fire resistance of laminated timber beams and columns. Fire Research Section, Division of
Building Research, National Research Council of Canada, Ottawa, Ont., Canada.
(2) Fackler, J. P., 1961. Essais de r6sistance au feu. Centre Scientifique et Technique du BAtiment, Cahier 415, et al.
APA
ABKJ1
ANDERSEN - BJORNSTAD - KANE - JACOBS
June 18th, 2018
Mr. Douglas McNutt
Principal
Salus Architecture
RE: Charring Calculation for Existing GIL Beam
Douglas,
At your request, I have reviewed the carrying capacity of the Glu-Lam (GL) beams based on a 1/40"
charring rate per minute.
I found that the exposed area of the 2nd floor 6 Wx 311/2" GL beam can handle 1/2 hour of charring
and still support unfactored (service level) loads at the factored or ultimate stress levels. This is apart
from any consideration of any of the three applied options: 2-layers of GWB protection (which
normally is counted as 1-hour rating) below the ceiling, shaft wall, or inturnescent paint, either of
which will increase the over-all resistance.
I also checked the roof 5 1/8"x27" GL beam capacity if charred and found that the roof GL can handle 1
hour of charring and still support unfactored (service level) loads at the factored or ultimate stress
levels, again without consideration of any of the three previously mentioned options.
Furthermore, I also used the method for calculating the fire resistance of Glu-Lam Beams found in the
APA document EWS Y245B "Calculating the Fire Resistance of Glu-Lam Beams and Columns", and
found that according to their method, the 2nd floor 6 Wx 311/2" GL beam would have 62.7 minutes
of fire resistance, and the roof 5 1/8"x27" GL beam would have 47.1 minutes of fire resistance.
Thus, for both GL types, it seems to me that the combination of 2 layers of or shaft wall or inturnescent
paint GWB (on the exposed sides of the GL) should be considered as more than adequate protection as
the GL beams would have a reserve of at least 30 to 60 additional minutes of capacity during charring
even neglecting the fire protective layers) before the beams would be overstressed at service load.
If you have any questions or need additional information, please feel free to call at 206-340-2255.
1402 - Third Avenue, Suite �
ABKJ1
ANDERSEN - BJORNSTAD - KANE - JACOBS
Sincerely,
Greg Lee, PE, SE
Principal
ABKJ Inc.
1402 - Third Avenue, Suite 200
VAIN
Protective Coatings
June 15, 2018
RE: Northpoint Recovery Center
To whom it may concern,
Albi would recommend applying 40 mils WFT (28 mils DIFT) of Albi Clad FP to protect the exposed glulam beams
and deck in place of using gypsum to provide a 1-hour fire resistance rating. This judgement is based on Western Fire
Center Inc. Report # 04042(a), where 40 mils WIFT of Albi Clad FP is specified for a 1 hour rating on an open wood floor
joist assembly featuring 2"xlO" joists and a deck of TG subfloor and CDX plywood.
Based on the Technical Note #EWS Y245B from the APA - Engineered Wood Association, the fire resistance
rating up to 1 hour can be calculated for glulam members. This method is recognized by the International Building
Code. Based on the calculations, the 6"x3l" beam has a fire resistance rating of 58 minutes and the 5.5"x27" beam has
a fire resistance rating of 53 minutes. These calculations were made assuming the beams would be carrying 100% of
their maximum design load. Based on this, 40 mils WIFT of Albi Clad FP applied to the exposed glulam beams will provide
the extra time necessary to achieve a 1 hour rating. Please note that Albi does not have any direct test data for Albi
Clad FP over glulam beams and this judgement is based on an established calculation method and indirect test data.
Brian Perry
Product Engineer
Albi Protective Coatings
401 Berlin Street, East Berlin, CT 06023
T 860 828 0571 Albi.com
02 Third Ave.
fj ISALUS s'4uite 200
Seattle, Wa
01 ARCHITECTURL 98101
(206)652-0722
JOB #: 16029
Kir'%Al 4 4 /nit -11 11.-11Z f1r'RArK1-r1
I 1UU0
(OOD
EDMONDS RECOVERY CENTER
NORTHPOINT RECOVERY
RATED CEILING AT GLULAM OPTION 1
E OF
30TH
L 2079
SD2.02
DATE: 06/18/18
REV TYPE: Author
ENGINEERING JUDGMENT FIRESTOP DETAIL NS14918024
*F Rating - 1 HR
mm
1. Floor/Ceiling Assembly (1 Hr) - Wood floor/gypsum ceiling assembly (UL L570 Design).
2. Penetrant - Max 20' long x 6" wide x 27" tall (or smaller) glularn beam. Penetrant to be rigidly supported. Annular
space is min 1/4" to max 3/4".
3. Sealant - SpecSeal@ SSS or LCI Sealant applied into annular space to full depth, flush with bottom of gypsum
ceiling.
*Note: 1 - Rating of the firestop system is dependent on the performance of the surrounding construction under
fire exposure with a maximum possible F rating of 1 Hr.
THIS DESIGN REPRESENTS A FIRESTOP SYSTEM EXPECTED TO PASS THE STATED RATINGS IF TESTED
Project: Signature: System Reference:
Northpoint Recovery Center W-L-1461, W-L-7244, F-C-7045
Project Address: Edmonds, WA 98020
Designed by: Bernadette Guerrero
Douglas McNutt/RMI N.T.S. 1' "05/302018 1 PAGE 1 OF 1 ,=" ASTM E814/UL 1479: Standard for Fire
ion Fi—tops
All statements, technical information, and recommendations contained herein are based
upon tests we believe to be accurate; however since the conditions of use and application
90 Spectifted Technologies Inc. are beyond our control, STI shall not be liable for any damage, direct or consequential,
OT114fans Way - goemMile, NJ 0076 USA- Toll Fra: MOM2.1111110 - T.' +1 "52MM resulting from the use of this material or design. STI's sole warranty shall be to refund or
P44"2SI-8416-E:twhiorvCWAred6p.oach-www.dMtwop.ow replace materials found to be defective.
KIMAI 4 4 /1111 -rL_llf�lZ
D
SECTION
02 Third Ave. EDMONDS RECOVERY CENTER
0Pj ISALUS s'4.ite 200
Seattle, Wa
01 ARCHITECTURL 98101 NORTHPOINT RECOVERY
(206)652-0722
JOB #: 16029 RATED CEILING AT GLULAM OPTION 2
79
SD2.03
DATE: 06/18/18
REV TYPE: Author
1402 Third Ave.
fj ISALUS Suite 200
Seattle, We
01 ARCHITECTURE 98101
(206)652-0722
JOB #: 16029
['111 M&WMAIKINKMAILME MINI MAO 1FAMAJ 40
9111111161 ME
pw '
WATITO As- I
EDMONDS RECOVERY CENTER
NORTHPOINT RECOVERY
RATED CEILING AT GLULAM OPTION 3
4NELS
OF 5/8"
)ERSIDE OF
�T AT BOTH
VITH UL 2079
IT
POSED
SD2.04
DATE: 06/18/18
REV TYPE: Author
Calculating fi�re Resistance
of Glulam Beams and Columns
77�7$ ;5 Py- " -�t t'y- r CAa ri-
Number EWS Y245B
December 2009
INTRODUCTION
Glulam beams and columns provide architectural warmth and beauty along with structural strength and natural
fire resistance. In the presence of fire, the outer portion of a glulam member becomes charred. This layer of charred
wood then functions as an insulator, helping to protect the undamaged interior of the member from the heat. The
rate of advancement of this insulating char layer into the remaininy— un a na,-rl- portion oLthe member has been
well documented (approxiTItely.0.025 inches [0.6 mm] per minute) and forms the theoretical basis of the equations
used to predict fire endurance� Full-scale fire tests on loaded beams and columns' have confirmed the validity of
the equations in predicting their load -carrying capability under fire conditions and the method is recognized by the
International Building Code (IBC).
DESIGN METHODOLOGY
Calculation of the ability of a glulam beam or column to resist fire for up to one hour is described in the 2009
International Building Code (IBC), Section 721.6. The equations apply to members with fire on three or four sides.
Beams:
Fire on 3 sides
t = 2.54ZB14 — 1�1 ..............
D
(1)
Fire on 4 sides
t = 2.54ZB 4 _ 2B
1 D I ............
(2)
Columns:
Fire on 3 sides
t = 2.54ZB 3 — B .............
1 2DI
(3)
Fire on 4 sides
t = 2.54ZB 3 — 1
1 DI ..... I ........
(4)
Where:
t = fire resistance in minutes
Z = partial load compensation factor (see Figure 3) which is a function of applied load to design capacity
B = the breadth or width of a beam or the smaller dimension of a column (in.) (see Figure 1)
D = the depth of a beam or the larger dimension of a column (in.) (see Figure 1)
(1) Lie, T. T., 1977. A method for assessing the fire resistance of laminated timber beams and columns. Fire Research Section, Division of
Building Research, National Research Council of Canada, Ottawa, Ont., Canada.
(2) Fackler, J. P., 1961. Essais de r6sistance au feu. Centre Scientifique et Technique du BAtiment, Cahier 415, et al.
APA
These equations apply to glulams with a minimum
nominal size of six inches by six inches before expo-
sure to fire. Equation 3 is accurate only when the
smallest dimension (B) is the side not exposed to the
fire. When a beam or column is partially recessed
into a wall, floor or ceiling, the full dimension of
the member, including the portion of the column
recessed into the wall, floor or ceiling may be used
in the calculations to obtain the maximum calcu-
lated fire resistance.
Equations 3 and 4 are slightly altered from the way
they appear in the IBC. In the column equations,
the dimensions B and D are reversed to maintain
consistency and clarity of notation on glulam beams
and columns (see Figure 1). B is assumed to be the
narrowest dimension of the column (weak axis
buckling).
Tables la, lb and lc show the minimum dimensions
FIGURE 1
DIMENSIONS FOR CALCULATION OF FIRE RESISTANCE
Where B is always the lead dimension.
T
D
B
D 01'
B
B D
Beam Column
of a glularn member that will provide 100 percent
design capacity and one -hour fire protection. These tables have been generated using Equations 1-4
Beams and columns with dimensions less than those shown in Tables la, lb and 1c, but at least 6 inclies by
6,inches nominal size, may meet the requirements
for one -hour fire resistance when the member is
over -designed for the applied load. This principle
is demonstrated in the design examples that follow.
SPECIFYING A ONE -HOUR
FIRE -RATED GLULAM
Tension laminations of glularn beams are always
positioned as the outermost laminations of the
beam subjected to maximum tension stresses, and
in a fire, the outermost fibers in a wood member
are the first to be damaged. For this reason, when a
one -hour rating is required for a glularn beam, the
designer should specify one additional tension lami-
nation in place of a core lamination (see Figure 2)
and the glularn should be marked "Fire -rated one -
hour" by the manufacturer. For a balanced beam
layup, an additional tension lamination should be
added to both outer zones. An additional tension
lamination is not required for columns and arches.
FIGURE 2
TYPICAL UNBALANCED GLULAM BEAM LAYUPS
FOR UNRATED AND ONE -HOUR FIRE -RATED GLULAM
One extra tension lamination added for one -hour resistance.
Outer Compression
Outer Compression
Inner Comp.
Inner Comp.
Inner Comp.
Inner Comp.
Core
Core
Core
Core
Core
Core
Core
Core
Core
Core
Core
Inner Tension
Inner Tension
Inner Tension
Inner Tension
Extra Outer Tension
Outer Tension
Outer Tension
Unrated
One Hour
TABLE 1 a
Member Type Beam
Fire Exposure Fire Three Sides Fire Four Sides
Beam Width (in.) 6-3/4 8-1/2 8-3/4 10-1/2 10-3/4 6-3/4 8-1/2 8-3/4 10-1/2 10-3/4
Minimum Depth (in.): 13-1/2 - 7-1/2 - 6 27 - 13-1/2 - 12
1- 1 /2" thick Laminations
Minimum Depth (in.): 13-3/8 6-7/8 - 6-7/8 27-1/2 13/3-4 - 12-3/8 -
1-3/8" thick Laminations
TABLE 1 b
Member Type Column
Fire Exposure Fire Three Sides*
K.1/d Condition(,) I I >11
Column Width (in.) 8-1/2 8-3/4 10-1/2 10-3/4 8-1/2 8-3/4 10-1/2 10-3/4
Minimum Depth (in.): - 9 - 7-1/2 - 15 - 10-1/2
1- 1 /2" thick Laminations
Minimum Depth (in.): 8-1/4 - 8-1/4 - 19-1/4 - 9-5/8 -
1-3/8" thick Laminations
*Minimum dimensions are only valid when the unexposed side of the column is the smaller side.
(a) See Figure 8.
TABLE I c
Member Type Column
Fire Exposure Fire Four Sides
K.1/d Condition(a) I I >11
Column Width (in.) —8-1/2 8-3/4 10-1/2 10-3/4 8-1/2 8-3/4 10-1/2 10-3/4
Minimum Depth (in.): - 12 - 10-1/2 - 30 - 13-1/2
1- 1 /2" thick Laminations
Minimum Depth (in.): 12-3/8 - 9-5/8 - 38-1/2 - 13-3/4 -
1-3/8" thick Laminations
(a) See Figure 8.
General Note for Tables la, 1 b and 1c:
Glulam members having a net width of 8-1/2" or 10-1/2" are typically manufactured using 1-3/8" thick laminations. Glularn members having a net
width of 8-3/4" or 10-3/4" are typically manufactured using 1-1/2" thick laminations.
FASTENERS
Because metal fasteners conduct heat directly into the member, exposed fasteners must be given rated protection from
fire that is equivalent to that expected of the member. For a one -hour rating, sufficient wood, gypsum wallboard or
other material must be applied to protect the exposed portions of the fasteners for one hour. This may be 1-1/2 inches
(38 mm) of wood, 5/8 inch (16 min) Type X gypsum board or other approved material. Example details can be found
in Figures 9-14.
DESIGN EXAMPLE 1: GLULAM REAM FOR ONE-NOUR FIRE RATING
IN ACCORDANCE WITH THE 2009 INTERNATIONAL BUILDING CODE
Assume a simply supported roof beam is to span 30 feet, carry 240 lb/ft of total load (dead load plus snow load) and
be used in a dry service condition. It is continuously supported along its compression side and will have three sides
exposed to fire. A one -hour rating is required. The beam used will be a 24F-V4/DF (Douglas -fir) with the following
allowable design stresses:
Fb 2400 psi
E 1.8 x 101 psi
Fv 265 psi
What size glulam beam should be used?
From Table 3 of EWS Data File Glued Laminated Beam DesigA Tables, Form EWS S475, select a 5-1/8 x 15 beam with
total capacity of 266 plf, which is greater than 240 plf. (Note that the tabulated capacity in EWS S475 has considered
the dead weight of the beam.)
Determining the actual beam depth that will continue to carry the design load for one hour is aided by the use of
Figure 4, Beams - Fire 3 Sides. From this graph, the range of depths that might be practical to use can be anywhere
from approximately 12 to 30 inches. Obviously, this beam must be deeper than 15 inches as the beam in this exam-
ple is stressed to approximately 90 percent of design capacity.
All of the 5-1/8-inch-wide beams in the depth range of 12 to 30 inches will retain 50-60 percent of design capac-
ity after one hour. An initial estimate of a percentage that corresponds with this range of beam depths is 55 percent,
which corresponds to a beam depth of 18 inches.
Section modulus, S = 5.125(18)2 = 276.75 in.'
6
Determine if this beam will have sufficient strength left after one hour of fire exposure to continue to carry the design
load by determining the ratio of applied moment to design flexural capacity. Beam size will also have to be checked
for shear and deflection.
Determine Fb'
12)-L (5.125)TIO (21)-�10
Volume factor = C, = ( 10 B L
(L2 I (5.125)T'Lo (Ll)'
18)" _�._1_25 30 To = 0.9266
Fb' = FbC,C, = (2,400)(1.15)(0.9266) = 2,557 lb/in?
Determine fb
Calculate beam weight using 35 lb/ft3
Beam weight = (5.125)(18)(12) (35) = 22.4 lb/ft
123
M Applied = w L 2 = (240 + 22.4) 30' = 29,520 ft-lb = 354,240 in.-Ib
T __iT
f b 354,240 = 1,280 lb/in.2
S 276.75
Check the ratio of applied moment to flexural capacity
fb 1,280
Fb' 2,557 : 0.50 < 55% => OK
Check fire endurance:
From Figure 3, for a beam loaded to 50% of capacity, Z is approximately 1.3.
Using Equation 1:
t = 2.54(l.3)(5.125) 4 — 5.125] = 62.9 minutes > 60 => OK; use 5-1/8-inch x 18-inch 24F-V4 Douglas -fir glulam beam.
1 18
This beam has a moment capacity that is significantly greater than is needed if the one -hour fire resistance is not a
requirement. In some cases, a wider beam may be required to satisfy a beam depth limitation while still meeting the
one -hour fire resistance requirement. For instance, a 6-3/4-inch-wide beam that is 13-1/2-inch deep, and has the
extra tension lamination, will carry 100 percent of its design load after one hour of fire exposure on three sides. See
Table la and Figure 4.
The designer will also need to confirm that the design shear and deflection values for the trial beam size are less than
50 percent of these capacities.
When specifying the beam, advise the manufacturer to eliminate one core lamination and substitute one additional
tension lamination (Figure 2) and mark the beam "Fire -rated one -hour."
ALTERNATIVE SOLUTION IN ACCORDANCE WITH THE
2005 NATIONAL DESION SPECIFICATION, CHAPTER 16
Step 1: From Table 3 of Data File, Glued Laminated Beam Design Tables, Form EWS S475, select a 5-1/8-inch by 15-inch
beam with total capacity of 266 plf which is greater than 240 plf (note that the tabulated capacity in
EWS S475 has considered the dead weight of the beam).
Step 2: Determine the actual beam depth that will continue to carry the design load when exposed to a one -hour fire
as follows:
Step 2a: From Chapter 16 of NDS,
1.2%
tO. 187
Where:
P = nominal char rate of 1.5 in./hr
Pe.ff = effective char rate (in./hr)
t = exposure time (hrs)
Therefore, when t = I hr, P,ff = 1.8 in./hr
Step 2b: The residual cross section after a one -hour fire exposure on three sides (top of the beam is protected from fire
damage) can be calculated as:
bresidual � 5.125 — (1.8 x 2) = 1.525 in.
h residual = 15 — 1.8 = 13.2 in.
3
Sresidual = 1.525 x 13.22/6 = 44.3 in.
Step 2c: The residual moment capacity after a one -hour fire exposure on three sides can be calculated based on Table
16.2.2 of the 2005 NDS.
Mresidual � 2.85 F b? X Sresidual � 2.85 x 2,400 x 0.9437 x 44.3/12 = 23,821 ft-lb.
Where:
Fb' = adjusted allowable bending stress, including beam volume effect factor, but not the load duration factor.
0.9437 = glulam beam volume effect factor (see Appendix A of EWS S475)
Step 2d: The applied moment due to the 240 lb/ft of total load and the beam weight of 18.7 lb/ft can be calculated as:
M.pplied wV = (240 + 18.7) x 302 = 29,102 ft-lb > 23,821 ft-lb =� NG
8 8
Step 2e: Therefore, the beam size should be increased to accommodate the one -hour fire exposure. Select a 5-1/8-inch
by 18-inch beam. From Table 3 of EWS S475, the load carrying capacity of this beam is 470 plf which is
greater than 240 plf.
Step 2f. Repeat Steps 2b and 2c for one -hour fire exposure,
bresidual = 5.125 — (1.8 x 2) = 1.525 in.
hresidual = 18 — 1.8 = 16.2 in.
2 3
S.idual = 1.525 x 16.2 /6 = 66.7 in.
Mresidual = 2.85 Fb' X Sresidual = 2.85 x 2,400 x 0.9266 x 66.7/12 = 35,213 ft-lb.
Ma O)e2 _ (240 + 22.4) x 302 = 29,522 ft-lb < 35,213 ft-lb => OK
pplied = 8 8
Therefore, use a 5-1/8-inch by 18-inch 24F-V4 Douglas -fir glulam beam.
DESION EXAMPLE 2x GLULAM COLUMN FOR
ONE-NOUR FIRE RATINO IN ACCORDANCE WITH
THE 2009 INTERNATIONAL BUILDINO CODE
An existing building is to be remodeled with a change of occupancy requiring that the glulam columns meet a one -
hour fire -resistance requirement. The existing glulam column is 20-foot high, measures B = 8-3/4-inches wide by D =
10-1/2-inches deep and will remain dry in service. It supports a concentrated total floor load (DL + LQ of 50,000 lb.
(CD = 1.0) applied concentrically to the top of the column. The column is not subjected to any lateral loads. From
the original specifications, the glulam is a Douglas -fir Combination 2 (see Table 3, Form EWS Y240). Determine if
the column is adequate to carry the imposed axial load for one hour with fire on four sides and how long it can be
expected to carry the applied load. If it is not adequate, determine what size column is required.
To address these issues, the total load capacity of the column must be determined along with the percentage of the
total load capacity used by the applied load and the partial -load compensation factor, Z.
Determine Load Capacity
B = 8.75 in.
D = 10.5 in.
A = B x D = 8.75(10.5) = 91.875 in.2
CD = 1.0 for DL plus floor LL
E = 1,600,000 lb/in.1
F, = 1,950 lb/in.1
C = 20(12) = 240 in.
K, = 1.0 (see Figure 8) Column is assumed to be pinned at both ends.
= f K� = 240(l.0) = 240 in.
= 240 = 27.43
B 8.75
c = 0.9
Where:
E = tabulated modulus of elasticity (lb/in.2)
E' = adjusted modulus of elasticity (lb/in .2)
F,� = tabulated compression design value parallel to grain (lb/in.1)
A = area of cross section (in.')
B = least dimension being evaluated for potential buckling (in.)
f = length of column (in.)
V, = f K, = effective length of column (in.)
Ke = buckling length coefficient for compression members
c = coefficient that depends on member type (0.9 for glularn)
(E'[1 - 1.645 COVE] 1.05) (1,600,000[l - (1.645)(0.10)] 1.05)
E'.,.. = 1.66 1.66 = 845,566 lb/in?
Where:
COVE = coefficient of variation in modulus of elasticity = 0.10 for glulam
1.05 = conversion factor to obtain true E (1.05 for glulam)
1.66 = factor of safety
FC* = tabulated compression design value multiplied by all applicable adjustment factors except CP (lb/in.1)
0.822 E'.i�. 0.822(845,566) 2
FcE = I ! ) 2 27.43 2 924 IbAn.
( B
FcE 924 0.474
F,* 1,950
+ JLL�J 2 (1
LE �E
Fc.* 1 + 0.474 1 + 0.474 0.474
.1(0.9) 0.440
CP = 2c 2c _c 2(0.9) � 1 0.9
F�' = F,:*Cp = allowable compressive stress (lb/in.2)
F�' = 1,950(0.440) = 857 psi
Axial load capacity = AFC 91.875(857) = 78,737 lb > 50,000 => OK for concentric axial load without fire endurance
consideration
Check fire endurance based on ratio of applied load to design capacity
Applied Load - 50,000 - 0.635 = 63.5%
Design Capacity 78,737
From Figure 7, for a column 8-3/4-inches wide and I./B > 11, 63.5% corresponds to about a 13-1/2-inch depth which
is greater than the existing column's depth of 10-1/2 inches. The existing column will therefore not carry the applied
load for the full duration of the prescribed one -hour fire.
To check this conclusion, calculate the fire endurance
From Figure 3, for a column with 1,/B > 11 and the load at 63.5% of capacity, Z is approximately 1. 16.
Using Equation 4:
B 8.75 in.
D 10.5 in.
t = 2.54ZB 3 — L = 2.54(l.16)(8.75) 3 — �1'75 = 56 minutes < 60 => NG
I D 1 1 10.51
The existing column is inadequate to meet the one -hour fire -resistance requirement even though it is adequate to
carry the applied load in occupancies not requiring a one -hour fire rating.
Determine column size necessary to carry the design load and meet the one -hour requirement
Using Figure 7 as a guide, try a 10-3/4-inch x 10-1/2-inch glulam, Douglas -fir Combination 2, assuming a depth of
10-1/2 inches is a design requirement.
A = 10.75(10.5) = 112.875 in.2
Slenderness ratio = I /B = 240/10.5 22.86
C
0.822 E'mj� = 0.822(845,566) 1,330 lb/in.2
F,:E e 2 22.861
F�* 1,950 lb/in .2
F, 1,330 0.682
Fc* 1,950
2 (,FcE)=
c* I + 0.682 1 + 0,6821 2 — 0.682 595
C, 2c 2c _c —T(0—.9) 2(0.9) 0.9
Fc' 1,950(0.595) = 1,160 lb/in .2
Axial load capacity = AFc' = 112.875(1,160) 130,939 lb > 50,000 lbs. OK
Check the fire endurance
Applied Load 50,000
= 0.382 = 38.2%
Maximum Capacity 130,939
Z, from Figure 3, is 1.3.
Using Equation 4:
B 10.5 in.
D 10.75 in.
t = 2.54ZB 3 — B I = 2.54(l.30)(10.5)13 — 10-5 = 70 minutes > 60 => OK-1
1 15- 10.751
use 10-3/4-inch x 10-1/2-inch Combination 2 Douglas -fir glularn column.
ALTERNATIVE SOLUTION IN ACCORDANCE WITH
THE 2005 NATIONAL DESIGN SPECIFICATION, CHAPTER 16
Step 1: The 8-3/4-inch by 10-1/2-inch glularn column capacity can be calculated based on Section 3.7.1 of the 2005 NDS
as 78,713 lb > 50,000 lb =:> OK
Step 2: Determine the actual column size that will continue to carry the design load when exposed to a one -hour fire
as follows:
Step 2a: From Chapter 16 of NDS,
1.2p.
P,ff � tO.187
Where:
P. = nominal char rate of 1.5 in./hr
P'ff = effective char rate (in./hr)
t = exposure time (hrs)
Therefore, when t = 1 hr, P,ff = 1.8 in./hr
Step 2b: The residual cross section after a one -hour fire exposure on four sides can be calculated as:
bresidual � 8.75 - (1.8 x 2) = 5.15 in.
hresidual = 10.5 - (1.8 x 2) = 6.90 in.
A,,sidual = 5.15 x 6.90 = 35.54 in?
Step 2c: The residual axial capacity after a one -hour fire exposure on four sides can be calculated based on Table 16.2.2
of the 2005 NDS.
Fc' = 2.58 x F, x CP = 2.58 x 1,950 x 0.1273 = 640.4 psi
Presidual = F.' x Aresidual = 640.4 x 35.54 = 22,755 lb < 50,000 1 => NG
Where:
Cp = column stability factor, which can be calculated based on Section 3.7.1 of the 2005 NDS with the exception
that the column buckling strength F�, is determined using equation given in Table 16.2.2 of the 2005 NDS
Step 2d: Therefore, the column size would need to be increased to accommodate the one -hour fire exposure. Select
10-3/4 inches by 10-1/2 inches. The column capacity can be calculated based on Section 3.7.1 of the 2005 NDS
as 130,939 lb > 50,000 Ib z* OK
Step 2e: Repeat Steps 2b and 2c for one -hour fire exposure,
bresidual � 10.75 - (1.8 x 2) = 7.15 in.
h residu.1 = 10.5 - (1.8 x 2) = 6.90 in.
Aresidual = 7.15 x 6.90 = 49.34 in.2
Fr' = 2.58 x F, x CP = 2.58 x 1,950 x 0.2253 = 1,133.3 psi
Presidual = F�' x Aresidual � 1,133.3 x 49.34 = 55,911 lb > 50,000 lb => OK
Therefore a 10-3/4-inch by 10-1/2-inch Combination 2 Douglas -fir glulam column is required to meet the one -hour
fire rating.
Summary
As shown by the preceding examples, glued laminated timber members can be designed to provide a one -hour fire
rating when required. Based on the 2009 IBC, Tables la, lb and Ic provide basic minimum dimensions for one -hour
fire -rated glulam beams and columns when the applied load represents 100 percent of the member design capacity.
Figures 4, 5, 6 and 7 provide estimated sizes of beams and columns that will satisfy a requirement for a one -hour fire
rating when the member is loaded to less than 100 percent of capacity. Alternatively, the design methodology pro-
vided in Chapter 16 of the 2005 NDS can be used to design one -hour fire -rated glulam beams and columns.
For additional information related to the design of glulams, contact APA Product Support Help Desk, 7011 South 19th St.,
Tacoma, Washington 98466-5333, Phone (253) 620-7400.
FIGURE 3
FACTOR Z AS A PERCENTAGE OF DESIGN CAPACITY
1.60
1.50
Columns — I,/B < 11
1.40
N
1.30
2 NNI
V
1.20 —
0
1.10 — Columns — 1�/B
and Beams
i.00 L
40 50 60 70 80 90 100
Applied Load or Bending Moment/Design Capacity (%)
FIGURE 5
BEAMS — FIRE 4 SIDES
30
25
20
.S 6-3/4 inchesA
15 8-3/4 inche
E
10
10-3/4 inches wide
5
01 1 1 1 1
50 55 60 65 70 75 80 85 90 95 100
Strength After One Hour (%)
FIGURE 4
BEAMS — FIRE 3 SIDES
4
35
30
5-1/8 inches wide
25
10 20
E
15
6-3/4 inches wide
10
5
01T
50 55 60 65 70 75 80 85 90 95 100
Strength After One Hour (%)
(Beams wide, than 6-3/4" will generally carry 100% of capacity
far 1 hour provided they are as deep as they are wide.)
FIGURE 6
COLUMNS — FIRE 3 SIDES
4)
35
6-3/4 inches wid
8—"/,
30 1� I I I
6-3/4 inches wide — le/B < 11
25
.S
20
E
0 15
10
1-0000' 1 4-7
1-, 8-3/4 inches wi e — �/B > 11
5
01
50 55 60 65 70 75 80 85 90 95 100
Strength After One Hour (%)
Calculating
Fire Resistance of Glulam Beams and Columns
[12
FIGURE 7
COLUMNS - FIRE 4 SIDES
40
6-3/4 inches wide - 1�/B > 11
oil
35
30
9 25
0 20
E
0 15
rwwwwbo
;PON'pom
..m
-
10
8-3/4 riches
wide -,],/B I I
5
1<
0
50 55 60 65 70 75 80 85 90 95 100
Strength After One Hour (%)
FIGURE 8
APPENDIX G, 2005 NDS - EFFECTIVE COLUMN LENGTH
Buckling modes
t t t
t
t
Theoretical K. value 0.5 0.7 1.0
1.0
2.0
2.0
Recommended design K,, when 0.65 0.8 1.2
1.0
2.1
2.4
ideal conditions approximated
Rotation fixed, translation fixed
Rotation free, translation fixed
End condition code
Rotation fixed, translation free
Rotation free, translation free
Form No. EWS Y245B N 0 2009 APA - The Engineered Wood Association n www.apawood.org
Calculating Fire Resistance of Glulam Beams and Columns L3
FIGURE 9 FIGURE 10
BEAM TO GIRDER — CONCEALED CONNECTION COLUMN CONNECTIONS — COVERED
Provide lateral support
for end of beams
. . ...........
P"
Wood beam
0 0
................
....................
\—Wood plug
Plan View
Standard steel
connections — box
Wood column
in using 2x wood
to protect steel
E
............
------------
Floor
Wood
cover typical bottom
and sides
----------
Elevation
Elevation
[Form No. EWS Y245B 0 2009 APA — The Engineered Wood Association m www.apawood.org
FIGURE 11
BEAM-TO-COLLIMN CONNECTION
Connection not exposed to fire
Provide lateral support for end of beam
Exposed
portion of beam
2x backup
nailer to box in
around beam
5/8" Fire -rated
gypsum board
0
0
0
Column enclosed within
0
one -hour wall. Column
may also be a concrete or
masonry pilaster, in which
case the beam -to -column
connection would be boxed
in with 2x4s and 5/8"
Elevation
fire -rated gypsum board.
FIGURE 12
BEAM -TO -COLUMN CONNECTION
Connection exposed to fire where
appearance is a factor
Provide lateral support for end of beam
End View
Wood plug
over bolt
Cross -
shaped
connection
recessed
in wood
Wood beam
;:(D Q Fill void
around seat
with plaster
of Paris or
Wood column approved
____/j _ compound
Elevation
Calculating Fire Resistance of Glularn Beams and Columns
15
FIGURE 13
FIGURE 14
BEAM -TO -COLUMN CONNECTION
CEILING CONSTRUCTION
Connection exposed to fire where
appearance is not a factor
Provide lateral support for end of beam
Standard one -hour rated ceiling framing
Steel connection
T.
welded to steel
plate cast in top of
7ailer
concrete column
5/8" Fire -rated 2.4 n strip
gypsum board
Apply fire protective coating
that is allowed by the code
Exposed portion
for one -hour rating of steel
of beam
Concrete column
Section
Elevation
F—Form No. EWS Y245B (9 2009 APA — The Engineered Wood Association www.apawood.org
Calculating Fire Resistance of
Glulam Beams and Columns
We have field representatives in many major U.S. cities and in Canada
who can help answer questions involving APA and APA EWS trademarked products.
For additional assistance in specifying engineered wood products, contact us:
APA HEADQUARTERS
7011 So. 19th St. - Tacoma, Washington 98466 - (253) 565-6600 - Fax: (253) 565-7265
R�-
PRODUCT SUPPORT HELP DESK
(253) 620-7400 - E-mail Address: help@apawood.org
DISCLAIMER
The information contained herein is based on APA — The Engineered Wood Association's continuing
programs of laboratory testing, product research and comprehensive field experience. Neither APA,
nor its members make any warranty, expressed or implied, or assume any legal liability or responsibility
for the use, application of, andlor reference to opinions, findings, conclusions or recommendations
included in this publication. Consult your local jurisdiction or design professional to assure compliance
with code, construction and performance requirements. Because APA has no control over quality of
workmanship or the conditions under which engineered wood products are used, it cannot accept
responsibility for product performance or designs as actually constructed.
Form No. EWS Y245B/Revised December 2009
APA
REPRESENTING THE ENGINEERED WOOD INDUSTRY