*Refer to IBC Section , applicable when fall protection is required. Glass stresses are designed for a safety factor of of 4.0 (IBC ).

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1 Architectural Railing Division C.R.Laurence Co., Inc E Vernon Ave. Los Angeles, CA (T) (F) JAN 2011 SUBJ: TAPER-LOC SYSTEM DRY-GLAZE LAMINATED GLASS GRS GLASS RAIL SYSTEM The GRS Glass Railing Dry Glaze Taper-Loc System utilizing 9/16 laminated tempered glass balustrade lights in an aluminum extruded base shoe serves as a guard for fall protection in structures. The system is intended for interior and exterior weather exposed applications and is suitable for use in all natural environments. The system may be used for residential, commercial and industrial applications. This is an engineered system designed for the following criteria: The design loading conditions are: Concentrated load = 200 lbs any direction, any location* Uniform load = 50 plf perpendicular to glass* Distributed load = 25 psf on glass area* Wind load = As stated for the application and components, 10 psf minimum. *Refer to IBC Section , applicable when fall protection is required. Glass stresses are designed for a safety factor of of 4.0 (IBC ). The system will meet or exceed applicable requirements of the 1997 Uniform Building Code, 2000, 2003, 2006 and 2009 International Building Codes, 2007 and 2010 California Building Codes, and 2007 Florida Building Code (as wind loading permits). Aluminum components are designed in accordance with the 2000 and 2005 Aluminum Design Manuals. Stainless steel components are designed in accordance with SEI/ASCE 8-02 Specification for the Design of Cold-Formed Stainless Steel Structural Members. Edward Robison, P.E.

2 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 2 of 16 Typical Installations: Surface mounted to steel with 12 o.c.: Residential, Commercial and Industrial Applications: Rail Height 36 or 42 above finish floor. Base Shoe Allowable wind load L56S Glass strength controls 1/2 Wedge-Bolt to 12 o.c. Rail Height 36 above finish floor. Base Shoe Allowable wind load L56S 47 psf Glass strength controls Rail Height 42 above finish floor. Base Shoe Allowable wind load L56S 35.3 psf Glass strength controls 1/2 x 6 lag screws to 12 o.c. Rail Height 36 above finish floor. Base Shoe Allowable wind load L56S 47 psf Glass strength controls Rail Height 42 above finish floor. Base Shoe Allowable wind load L56S 35.3 psf Glass strength controls Embedded base shoe: Glass strength controls for all cases ALLOWABLE LOADS ON GLASS Rail Height 36 above finish floor. Lam. Glass thickness Allowable wind load 9/ psf Commercial and Industrial Applications: Rail Height 42 above finish floor. Lam. Glass thickness Allowable wind load 9/ psf Based on safety factor of 4.0 on glass modulus of rupture. MAXIMUM GLASS HEIGHT FOR FALL PROTECTION IS 4-2 (50 ) REFER TO GRS ENGINEERING REPORT FOR CAP RAILS

C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 3 of 16 Taper-Loc System Typical Installation For two ply laminated glass with 1/4 Fully Tempered Glass and 1/16 interlayer maximum

3 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 3 of 16 Taper-Loc System Typical Installation For two ply laminated glass with 1/4 Fully Tempered Glass and 1/16 interlayer maximum glass light height is 42 : Edge Distance: 2 A 8 5/8 ; 51mm A 219mm Center to center spacing: 7 B 14 : 178mm B 356mm Panel Width/Required quantity of Taper-Loc Plates: 6 to 14 (152 to 356mm) 1 TL Plate 14 to 28" (356 to 711 mm) 2 TL Plates 28" to 42" (711 to 1,067 mm) 3 TL Plates 42" to 56" (1,067 to 1,422 mm) 4 TL Plates Minimum Glass Lite Width = 6 when top rail/guardrail is continuous, welded corners or attached to additional supports at rail ends. NOTES: 1. For glass light heights over 42 A max and B max shall be reduced proportionally. A max = 8 5/8*(42/h) B max = 14*(42/h) 2. For glass light heights under 42 A max and B max shall not be increased. 3. A min and B min are for ease of installation and can be further reduced as long as proper installation is achieved.

4 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 4 of 16 LOAD CASES: Dead load = 6.9 psf for glass 1.8 plf top rail 3.0 plf for base shoe Loading: Horizontal load to base shoe 25 psf*h or W*H Balustrade moments M i = 25 psf*h 2 /2 or M w = w psf* H 2 /2 1SF 50# 1SF 50# 200# or 50 plf For top rail loads: M c = 200#*H M u = 50plf*H WIND LOAD = w psf on face area LL = 25 PSF entire area including spaces H S FOR WIND SCREEN OR DIVIDER APPLICATIONS WHERE FALL PROTECTION IS NOT REQUIRED THE TOP RAIL MAY BE OMITTED. THE 200# LOAD, 50 PLF LOAD AND 25 PSF LOAD CASES ARE APPLICABLE TO GUARD APPLICATIONS ONLY. MINIMUM WIND LOAD IS 10 PSF

5 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 5 of 16 For wind load surface area is full area of guard: Calculated in accordance with SEI/ASCE 7-05 Section Design Wind Loads on Open Buildings and Other Structures. This section is applicable for free standing guardrails, wind walls and balcony railings because they are not part of the building structural frame, are open on all sides and do not receive loading from anything other than the railing surface. Section Components and Cladding is not applicable because the rails are not part of the building envelope but are outside of the building envelope. Section Parapets may be applicable when installed near the edge of a roof with GC pi = 0 so the equation simplifies to: p = q p (GC p ) = q z GC f. When acting as a parapet 4 load cases must be considered (windward and leeward zones 2 and 3). For guardrails the coefficients have the following values: G = 0.85 from ASCE/SEI 7-05 section C f = 1.2 From Figure Q z = K z K zt K d V 2 I Where: I = 1.0 K z from Table 6-3 at the height z of the railing centroid and exposure. K d = 0.85 from Table 6-4. K zt From Figure 6-4 for the site topography, typically 1.0. V = Wind speed (mph) 3 second gust, Figure 6-1 or per local authority. Exposure B Exposure C Exposure D Wind Speed K zt K d GC p Wind Speed K zt K d GC p Wind Speed K zt K d GC p Height K z q z p (psf) Height K z q z p (psf) Height K z q z p (psf) Wind Speed K zt K d GC p Wind Speed K zt K d GC p Wind Speed K zt K d GC p Height K z q z p (psf) Height K z q z p (psf) Height K z q z p (psf) Wind Speed K zt K d GC p Wind Speed K zt K d GC p Wind Speed K zt K d GC p Height K z q z p (psf) Height K z q z p (psf) Height K z q z p (psf) Wind Speed K zt K d GC p Wind Speed K zt K d GC p Wind Speed K zt K d GC p Height K z q z p (psf) Height K z q z p (psf) Height K z q z p (psf) Wind load may vary depending on site conditions and topography.

6 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 6 of 16 GLASS STRENGTH All glass is fully tempered laminated glass conforming to the specifications of ANSI Z97.1, ASTM C b and CPSC 16 CFR For the two ply 9/16 glass the minimum Modulus of Rupture F r is 24,000 psi. Allowable glass bending stress: 24,000/4 = 6,000 psi. Tension stress calculated. Glass is two ply 1/4 glass (t ave = 0.23 ) with 0.1 interlayer, t t = 2* = Bending strength of glass for the given thickness: S y = 12 * (t) 2 = 2* (t) 2 in 3 /ft 6 For two ply 9/16 glass the effective glass thickness is dependent on the rate of loading. For short duration loads (live and wind) effective thickness is 2x0.23 = 0.46 S y = 2*(0.46) 2 = in 3 /ft M allowable = 6,000psi* in 3 /ft = 2,539 #/ft = #/FT For very short duration loads (impacts) the effective thickness is the total thickness, t t. S y = 2*(0.52) 2 = in 3 /ft M allowable = 6,000psi* in 3 /ft = 3,245 #/ft = #/FT For long duration loads (dead or semi-permanent live loads) the effective glass strength is two times the strength of the thinnest ply. S y = 2*2*(0.23) 2 = in 3 /ft M allowable = 6,000psi* in 3 /ft = 1,270 #/ft = #/FT For cantilevered elements basic beam theory for cantilevered beams is used. M w = W*L 2 /2 for uniform load W and span L or M p = P*L for concentrated load P and span L, GLASS PANELS LOADS: From UBC Table 16-B or IBC At top 200lb concentrated or 50 plf Any direction Or On panel 25 psf horizontal load DETERMINE MAXIMUM PANEL HEIGHT: For 50 plf distributed load: h = (M a /w)= M a /50plf For 200# load, not top rail: h = M a *S/200# where S = light length

7 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 7 of 16 For 25 psf live load h = (M a *2/25 psf) 1/2 = (M a /12.5) 1/2 For wind load h = (M a *2/W) 1/2 maximum wind load for given light height: W = 2M a /h 2 Determine height at which wind load will control over 50 plf top load: M a = 50plf*h = W*h 2 /2 Solve for h: h = 2*50/W = 100/W or solve for W: W = 100/h or W*h = 100 Relationship of wind to height where wind load controls over 50 plf top load (See graph) Below line 50 plf top load will control design. For 200 lb concentrated load Worst case is load at end of panel top corner with no top rail: 200# load b1 b2 The load will be initially resisted by a strip = 8t For 9/16 glass = 4.48 The shear will transfer along the glass at a 45 angle to spread across the panel. b2 = b1+h 2 from top b2 = = 6.48 M = 200#*2 = 400 # S = 0.54* in 3 = in 3 f b = 400 #/ in 3 = 1,750 psi

8 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 8 of 16 Determine minimum panel width S (ft) for height h (ft) =3.5 : M = 200#*42 = 8400 # S yt = S y in 3 /ft*s = 2*t 2 *S M a = S yt *6,000psi S min = M/(S y *6,000) = 200*h/(2*t 2 *6,000) = h/(60*t 2 ) S min = 42/(60* ) = For lights smaller than top rail must be continuous to additional supports such as wall, post or larger glass lights. FOR 9/16 LAM. GLASS: Determine relationship between allowable wind load and wind screen height: For 50 plf distributed load: h = 211.6/50plf = 4.23 For 25 psf live load h = (211.6/12.5) 1/2 = For wind load h = (211.6*2/W) 1/2 W = 2*211.6/h 2 Maximum Height at 25 psf load = For h = 3, W = 211.6*2/(3 2 ) = 47 psf For h = 3.5, W = 211.6*2/(3.5 2 ) = 34.5 psf NOTES: Base Shoe anchorage may limit wind loads to less than that allowed by the glass strength. Specifier shall be responsible to determine applicable load cases and wind load.

9 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 9 of 16 DRY-GLAZE TAPER-LOC SYSTEM Glass is clamped inside the aluminum base shoe by the Taper-Loc Shoe Setting Plate (L shaped piece on the back side) and two Taper-Loc Shim Plates (front side). The glass is locked in place by the compressive forces created by the Taper-Loc shim plates being compressed together by the installation tool. Use of the calibrated installation tool assures that the proper compressive forces are developed. Until the shim plates are fully installed the glass may be moved within the base shoe for adjustment. Glass may be extracted by reversing the installation tool to extract tapers.

10 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 10 of 16 The Taper-Loc setting plate is bonded to the glass by adhesive tape to hold it in place during installation and to improve glass retention in the base shoe. Surface area of the setting plate adhered to the glass: A = 2 *2.5 = 5 in 2 adhesive shear strength 80 psi 3M TM VHB Tape Z = (2/3)*5 in 2 *80 = 267# minimum setting plate locks into place in the base shoe by friction created by the compression generated when the shim plates are locked into place. Installation force: T des = 250# design installation torque T max = 300# maximum installation torque Compressive force generated by the installation torque: C = (0.2*250# /1.0 )/ sin(1.76 ) C = 1,628# Frictional force of shims and setting plate against aluminum base shoe: coefficient of friction, µ= 0.65 f = 2*(1,628#0.65) = 2,117# Frictional force of shims against glass: µ = 0.20 f = 1,628*0.20 = 326# Resistance to glass pull out: U = 267#+326# = 593# Safety factor for 200# pullout resistance = 2*593/200 = 5.93 Based on two taper sets Minimum recommended installation torque: 4/5.93*250 = 169# Extraction force required to remove tapers after installation at design torque: T = 250*(0.7/0.2) = 875#

11 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 11 of 16 Glass anchorage against overturning: Determine reactions of Taper-Loc plates on the glass: Assuming elastic bearing on the nylon parts the reactions will have centroids at approximately 1/6*1.80 from the upper and lower edges of the bearing surfaces: R 1/6*1.80 = 0.30 From M about R CU = 0 0 = M+V*( ) - R CB *1.5 Let M = V*40 (42 total height) M a = 250# for 1/2 glass V = 250/3.33 = 75# substitute and simplify: 0 = V* R CB *1.5 Solving for - R CB R CB = 75*41.5/1.5 = 2,075# For C B = 3,000 psi: R CB = 3.5 *(1.8 /2)*3,000 psi/2 = 4,725# > 2,075# Bearing strength is okay M a = 2,075*(2/3*1.8 ) = 2,490# R CB = R CB +V = 2,075+75# = 2,215# At maximum allowable moment determine bending in base shoe legs: M i = C*( /3) M s = R CB [0.188+(1.8*2/3] M i = 1,628*(1.088) = 1,771# M s = 2,215 *(1.388) = 3,074# Strength of leg 14 length = 3,086# *14/12 = 3,600# Adjustment to allowable load based on base shoe strength: M a = 3,086/3,074*250# = 251# Allowable moment on system is limited to 250# based on maximum allowable glass moment for 9/16 laminated glass.

12 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 12 of 16 GLASS STRESS ADJUSTMENTS FOR THE TAPER-LOC SYSTEM The Taper-Loc System provides is a concentrated support: Stress concentration factor on glass based on maximum 14 glass width to each Taper- Loc set. Moment concentration factor Full scale tests and numerous FEA models indicate that there is no appreciable bending stress concentration associated with the concentrated point supports that the taper-loc system employs. This is because of the purely elastic behavior of the glass for short duration loads up to failure combined with the ratio of the glass height to clear spacing between supports being greater than 2. The glass curvature must be nearly constant across the width of the glass so bending stress must be nearly constant. Thus bending stress will be accurately modeled as constant across the glass width. F b = 6,000 psi Allowable bending stress based on an SF = 4.0 Shear concentration factor: Accounts for effect of point support C V = 14 /3.5 *(2-3.5/14) = 7.0 F Va = 3,000 psi maximum allowable shear stress Allowable Glass Loads: M a = S*6,000 psi V a = t*b/7.0 For 9/16 laminated glass, 12 width: M a = *6,000 = 2,539# = 211.6# V a = 0.46*12*3,000/7.0 = 2,366# Since shear load in all scenarios is under 10% of allowable it can be ignored in determining allowable bending since it has less than 1% impact on allowable bending loads or rail heights. Maximum edge distance for edge of glass to centerline of Taper-Loc plates: e des = 14/2 = 7 for design conditions (no reduction in allowable loads) e max = e + e des /2: (25*e*3.5 )+25*1.17*3.5 2 /2 = : solve for e e max = [ *1.17*3.5 2 /2]/(25*3.5) = 10.4 (to CL of Taper-Loc plates)

13 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 13 of 16 9/16 LAMINATED GLASS BASE SHOE L56S BASE SHOE 6063-T52 Aluminum extrusion Fully tempered glass glazed in place, using the Taper-Loc dry-glazing system. Shoe strength Vertical legs: Glass reaction by bearing on legs to form couple. Allowable moment on legs ADM Part 1B 3.4.4, and 4.4 M a = S*øF L or øf L = 1.3*0.95*F cy = 1.235*16ksi = ksi or øf L = 1.42*0.85*F u = 1.207*22ksi = ksi S y = 12 * */6 = in 3 /ft Z y = 12 * */4 = in 3 /ft øm n = 26.55ksi*1.125 in 3 /ft = 29,869# /ft or (controls) øm n = 19.76ksi* in 3 /ft = 33,345# /ft Service moment on base shoe: M s = øm n /λ = øm n /1.6 M s = 29,869# /ft/1.6 = 18,668# Leg shear bottom t min = 0.75 øf Ls = 0.95*16 ksi/ 3 = ksi V all = 0.75 *12 /ft*8.775 ksi = 79 k/ft Base shoe anchorage: Typical Guard design moment = 175# = 2,100# or (maximum allowable moment) = # = 2,539 # Based on glass strength Typical Anchor load 12 o.c. T a = 2,539 #/( ) = 1,766# For 1/2 cap screw to tapped steel, CRL Screw part SHCS12x34 or SHCS12x1 T n = A sn *t c *0.6*F tu where t c = 0.25 ; A sn = and F tu = 58 ksi (A36 steel plate) T n = *0.25*0.6*58 ksi = 9.63 k Bolt tension strength = 0.75*67.5 ksi* in 2 = 7.18 k Use 5/16 minimum for maximum load: Maximum service load: 7.18k/2 = 3,592# Maximum allowable moment for 12 on center spacing and direct bearing of base shoe on steel: M = 3,592#*[ *3,592/(30ksi*12)] = 5,146 # per anchor

14 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 14 of 16 3/8 x 4 screw in anchor into 4 deep holes manufactured by Powers Fasteners. Allowable loads based on ESR øn sa = 0.65*4,400# = 2,860# For concrete breakout strength: N cb = [A Nc /A Nco ]ϕ ed, N ϕ c, N ϕ cp, N N b A Nc = (1.5*2.25 *2)*(1.5*2.5*2) = 45.56in 2 Minimum edge distance is 3 3/8 A Nco = 9*2.5 2 = 45.56in 2 C a,min = 1.5*2.5 = 3.75 C ac = 2.5*2.5 = 6.25 ϕ ed,n = 1.0 ϕ c,n = 1.0 (from ESR-2526) ϕ cp,n = 1.0 (from ESR-2526) N b = 24*1.0* 3000* = 4,437# N cb = 45.56/45.56*1.0*1.0*1.0*4,437 = 4,437# From ESR-2526 anchor pull out does not control design øn n = 0.65*4,437# = 2,884# Anchor steel strength will not control Moment resistance of each anchor: øm n = 2,884#*[ *2,884/(2*0.85*3ksi*12)] = 4,146# = 345.5# per anchor M a = øm n /λ = #/1.6 = 215.9# (at 1 spacing develops full allowable glass load.)

15 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 15 of 16 Installation to wood: 1/2 x 6 lag screws into solid wood, Douglas Fir or Southern Pine or equivalent density wood. Typical anchor to wood: 1/2 lag screw. Withdrawal strength of the lags from National Design Specification For Wood Construction (NDS) Table 11.2A. For Doug-Fir Larch or denser, G = 0.50 W = 378#/in of thread penetration. C D = 1.33 for guardrail live loads, = 1.6 for wind loads. C m = 1.0 for weather protected supports (lags into wood not subjected to wetting). T b = WC D C m l m = total withdrawal load in lbs per lag W = WC D C m =378#/ *1.33*1.0 = 503#/in Lag screw design strength l m = 6-13/16-5/16 = T b = 503*4.875 = 2,452# Steel strength = 60ksi*A t /1.67 = 35.93ksi*0.110in 2 = 3,952# > 2,452# Z ll = 520# per lag, (horizontal load) NDS Table 11K Z ll = 520#*1.33*1.0 = 692# Z T = 320# per lag, (vertical load) Z T = 320#*1.33*1.0 = 425# Determine moment strength of anchorage: For pivoting about edge of base shoe: Required compression area based on wood strength: F ct = 560psi; F ct *C d *C b = 560psi*1.33 = 745psi For C = T =2,000# A = 2,000#/745psi = 2.685in 2 b = A/(12 ) = 2.685/(12) = M a = 2,000#*( /2) = 2,651# = 220.9# For 12 o.c. spacing NOTE: DO NOT DIRECTLY LAG BASE SHOE TO WOOD WHERE EXPOSED TO WEATHER OR DIRECT SUNLIGHT BECAUSE BASE SHOE WILL LOOSEN WITH TIME AND WILL NOT BE ADEQUATELY ANCHORED.

16 C.R. Laurence GRS with 9/16 Laminated Glass in L56S Base Shoe Page 16 of 16 Side mounted base shoe: Verify Anchor Pull through For counter sunk screw P nov = ( t/D)DtF ty =( *.5*/.5).5*.5*16 ksi P nov = 6,880# For inset bolt t min = 0.25 P nov = F tu / 3*(A v ) A v = 0.25 *π*.75 =0.589 in 2 P nov = 30ksi/ 3*(0.589 in 2 )= 10.2k For standard installation, 42 guard height and 25 psf max uniform load Anchor Load T a T a = M a /2 T a = 2,100 #/2 = 1,050# For anchor into concrete: 3/8 diameter x 4 Screw-in anchor Powers Wedge-Bolt (CRL #WBA38X4) Strength same as previously calculated, T a = 2,884# Lag screw strength same as previously calculated. Note: Fascia mounted base shoe may be directly lagged to wood beam where weather exposed because of reduced wood stresses.

10012 Creviston DR NW Gig Harbor, WA fax

10012 Creviston DR NW Gig Harbor, WA fax C.R. Laurence Co., Inc. ATTN: Chris Hanstad 2503 East Vernon Los Angeles, CA 90058 27 March 2013 SUBJ: CRL SRS STANDOFF RAILING SYSTEM GLASS BALUSTRADE GUARDS The SRS Standoff Railing System is an engineered