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The Specification, Design Manufacturing and
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Learnin Ob ectives
pon omp e on o s c ourse e es g n ro ess o na w eable to:
Solution
Exp la in a pp lic a tions for Proprieta ry LGST
Spec ify LGST Desc ribe the design proc ess for Fac tory-built LGST , , ,
Fac to ry-built LGST
Compare and c ontrast a n LGST p roposa ls and exp la in whatma kes a c om lete truss s stem
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Wh Li ht Gau e Steel Trusses?
erever s eep sope , res en a -s y eroofs a re desired
Non-c ombustib ility is manda ted
The IDEAL solution is...
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Li ht Gau e Steel Trusses
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The Advanta es
1. 100% non-combustible2. Lon c lea r-s an ca ab ilities
A. LGSTs c an typ ic a lly span 80+ feet, depend ing on load ingcriteria.
B. Obviously, spans will va ry grea tly between snowy reg ions suc h
as New Eng land and warmer c lima tes like Texas.3. Limitless roof and c eiling p rofiles--just like wood trussesA. Eng ineers ha te to hear this, but w ith the c omputer software
availab le today, designs c an be more d ynamic than ever.4. Lightweight
A. LGSTs a re typ ic a lly ha lf the weight of wood trusses due to the irg strengt to we g t ra t o.
B. This is an advantage for long spans and heavy conc entra tedloads sinc e the trusses are not ha ving to work doub le duty to
sup por emse ves a s we a s e oa s e ng a pp e .
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The Advanta es
- -. A. Proprieta ry trusses are designed by experts, and sea led by
veterans in the light gaug e truss business.
A. Often sp rinklers c an be d ownsized or even elimina ted whenthe roof struc ture is built from c ompletely non-c ombustib lemateria ls. There is nothin to burn!
7. Compatib le w ith a lmost any dec king / roofing systemA. There a re fastening methods tha t c an effec tively hand le
c onnec tions to everything from p lywood and meta l dec k tounique mate ria ls like Struc tural Insula ted Pane ls or SIPs.
8. Relieves design firms of costly, time c onsuming roof design work--frees them up for more p roduc tive endea vorsA. Bec ause the design software hand les the eng ineering , sizing
of materia ls and c a lc ula tion of loads, a rc hitec ts andeng ineers c an simp ly spec ify tha t LGSTs be used, p rovide the
asc esgn c r te ra an pro es. e truss esgner can ta eit from there.
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LGST a re an idea l substitute for
Bar Joists
Red IronConcrete
Fire
Wood
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Almost an Confi ura tion is Possib le
Radius forms
Bow string trusses
Sc issor trusses
Almost any Configuration is Possible
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The LGST Marketp lac e
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The Market Toda - Commercial/Institutional
n o ay s mar e , e es p ro ec s o a e a van age oLGSTs are c ommerc ia l and institutiona l p rojec ts. These a re
typ ic a lly la rge p rojec ts in d iverse market segments.,to d ra in from the roof a rea and red uc ing the c hanc e for lea ks.
Tighter c ode enforc ements a re requiring tha t more a nd more- .
LGSTs are popular in high g rowth segments, areas tha t a resee ing la rger than normal c onstruc tion g rowth.
years, and C-stud trusses ha ve been used for 30+ years, they
are still c onsidered Up and Coming in the d esign community.Certain markets have b e un to emb rac e the fea tures andbenefits of LGSTs. Others still view them as new or do no t knowabout them a t a ll. There is still a lot of ed uc a tion to be done.
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Applications
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A lic a tions
There a re many typ es of struc tures tha t a re ana tura l fit w ith LGSTs
We will look a t a few of the most c ommonapplications
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Assisted Livin
These struc tures a re a growingmarket as our popula tionages. The c ombina tion of
noncombustible structuresand the desire for a Residentia l Look bode wellfor LGSTs.
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Educational
sc hools as well as dorms anduniversity b uild ing s a ll p resent
roo fs that need non-combustible structures. In
,
c overing over fla t roofs of 30yea r old sc hools a re a grea to t ion that save lots ofmoney for sc hool budgets.We will look a t a c ase stud yfurther into the c ourse tha tillustra tes the opportunities forold sc hool roofs to bec hanged d rama tic a lly.
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Offices
Offic e c onstruc tion is another growing opportunity for LGSTs. Ag a in,c odes require non-c ombustib le c onstruc tion. In add ition, in somearea s c odes require offic e build ings to c omp lement the surround ing
arc hitec tura l landsc ape, whic h may reflec t residentia l design.
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Correctional
n ortunate or soc ety,but g ood for business,
Correc tiona l Fac ilitiesa re a no er grow ngsegment for LGSTs.
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Banks/Financial
oney s a r enoug o eep w ou go ng up n ames
Non c ombustib le materia ls a re a must for fina nc ia l institut ions.
Some U.S. suburban b anks tend to have more of a residentia llook as well.
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S orts/ Rec rea tiona l
e nc rease o newstadiums for professional
teams as well as the new
sports c omplexes, thissegment is a lso growing .
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Li ht Industria l
op portunity to app ly the look
of residentia l roofs towarehouse fronts and offic espac es that a re p a rt ofwarehouses.
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Hos ita lit
esp e e ups an owns o e mar e , osp a y s oua lways be a growing and c ha ng ing industry. LGSTs provide
grea t solutions for two build ing methods; as the c omp lete roof
handling a nd o ther mec hanic a l devic es p lac ed on the roo f.
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Retail/Mansards
When residential c onstruc tion goes on the rise, strip shopp ing c enter
c onstruc tion often follows. LGSTs are often used to frame out thesestruc tures.
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Other Build in T es Ma Inc lude
ea ers Military Housing
Sta d iums Water Trea tment Fac ilities
Fire Stations Libraries an so on.
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Case Stud ies
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Case 1
ro ec - urs ng ome o un ce,Eunic e, LA
, sq . . asss e v ng ac y Light gauge framing spec ified for
non-combustibility ,
stic k framed with studs LGST fab ric a tor designed and
, By utilizing pre-fabric a ted trusses, the
c ontrac tor estima ted they saved 24-framing . There were a lot of savingsrea lized , not to mention the b ene fitsin sc hedulin !
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Case 2
ro ec - a ar e ss . v ng,
Livonia, MI
Five build ing s to ta ling 35,000 ft2
20 yea r old Fire reta rdant wood rooftrussesa nd p lywood dec king litera llyfalling apart--trusses breaking, sagging,
dec king c rumb ling Insurance c ompany req uired c omp lete
rep a cemen an or c over ng o ex s ngroof
LGST fab ric a tor stepped in with severa l
The utility b uild ing trusses and dec k wereto rn o ff in sec tions and Ultra-Span trusses
.
and were a ttac hed to steel trusses
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Case 2
The four residentia l units p rovedto be more c ha lleng ing. Themec hanic a l and elec tric a l
systems were running THROUGH Light gaug e sc issors trusses
were designed to fit ove r theexistin roof and take over
t e truss system n or er orthe wood trusses to be pulled ,a ll the mec hanic a ls would
the loa d handlingresponsibilities. Light gaugetrusses were p lac ed over the
ave o e pu e an e
residents reloc a ted during theentire p roc ess
top of the old truss system,elimina ting the need to (1)
remove the mec hanic a l andelec tric a l systems, and (2) theresidents were ab le to rema inin their homes, elimina ting a
ot o stress a n expense oreveryone!
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Case 3
ro ec - owar . nn s c oo
30+ yea r old fla t roof leaking like a
Add itiona lly, sc hoo l boa rd wantedto c onc ea l new roo ftop AC units
built-in mec hanic a l spac e Sing le row of stub c olumns insta lled
Roof penetra tions red uc ed fromhund reds to only 50
Entire re-roo f c om leted in twoweeks with no c lass interrup tion
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Truss Systems
C iti l El t f C h i
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Critic a l Elements of a Comprehensivepec c a on
s a re g y eng neere u ng c omponen s. ouproper design, qua lity c ontrol, and p rec autions, serious p rob lemsc an arise. In order to ensure tha t a qua lity produc t is p rovided ,
- .
The following examp les illustra te the d ifferenc e between fac tory. .
method would you p refer for your p rojec t?
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Whic h is More Prec ise?
.
Versus This!
C iti l El t f C h i
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Critic a l Elements of a Comprehensivepec c a on
n a on o e ng ac ory- u , c omp e e eng neer ngand tec hnic a l sup port is a must. All truss-to-truss, truss-to-
bearing c onnec tions, and system b rac ing spec ific a tionsmust be p rovided by the truss supp lier. Inc lud ing spec s for100% mill c ertified steel and UL c lassific a tions whenre uired . These elements a re c ritic a l. The must be
spec ified and enforc ed or someone w ill likely attemptshortcuts.
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Cost Effec tive LGST Assemblies
Another benefit to spec ifyingLGST from a proprieta ry sup p lieris the ava ilab ility o f UL ra tedtruss assemb lies. Assemb lies
from proprieta ry sup p liers a reab le to ac hieve 1-2 hour ra tingsw on y one a yer o gyp sum,c ompared to wood truss
assemblies tha t must use two.
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T ic a l Commerc ia l Assembl
our + w on y onelayer of Type C p itc hedtruss with insula tion on
sys ems a re a e oac hieve the UL ra tingswhile ma inta ining the
5
6
p rac tic e o f 48 inc hes oncenter.
3
4
1
7 8
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Design of Fac tory-built LGST
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Desi nin Fac tor -built LGST
oug propr e ary russ sys ems are a new me orela tive to other framing systems like red iron and bar joist,
they are modeled a fter the wood truss industry, a strongforty-yea r history with a p roven trac k rec ord of qua lity andc ost effec tiveness. Tha t trad ition, c ombined with best ofb reed desi n softwa re, ma kes for a ver owerful tool.
Truss design software a llows fabric a to rs to design w ithspeed , ag ility, and a c c urac y. Mod ific a tions c an be
budgets and fine tuned estima tes. CAM andmanagement tools a re a lso a rea lity with truss design
.
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Sta te-of-the-a rt Design Software
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SoftwareSoftware
There are three ma in steps to designing
Design, and Cost Estima ting. Mostp roprieta ry systems p rovide these threeelements to the truss fab ric a tor. It is the
job of the fa bric a tor to inp ut thebuild ing information into the softwa re.
D i i F b il LGST
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Desi nin Fac tor -built LGST
e o ow ng proc ess s yp c a or pu c y russ wor :
Onc e the b id for trusses is awarded , eng ineering d rawings are
- ,d rawings are reviewed and sea led . Connec tions, b rac ing, andother spec ia l servic es may a lso b e requested . At tha t point, the
,
(typ ic a lly multip le c op ies), in less than 48 hours. Sub mitta ls a rethen made to the a rc hitec t, c ontrac tor, and projec t engineer
.
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Parameters Effec ting LGST Cost
D i F t I t i T C t
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Desi n Fea tures Im ac tin Truss Cost
Roof p itc h and heel height a re two o f theTruss Cost vs. Span
6" Heel Height, Variable Roof Pitch
most c ritic a l elements that c an effec t thec ost of a truss system. Based on these
graphs whic h have been d evelop ed over5.506.50
7.50
8.50
s
t,$persqft
2:12
3:12
a period of severa l yea rs, you c an seetha t a s span inc reases, steeper slopes a reab le to keep the c osts lower. Also,
1.50
2.50
3.50
4.50
TrussMaterialC 4:12
5:12
6:12
nc rea sng e ee e g a ows or a
more effic ient and therefore more c osteffec tive d esign.
20 30 40 50 60 70
Span, ft
Truss Cost vs. Span
10" Hee l Height , Variable Roof Pitch
5.005.50
ft
2.50
3.00
3.50
4.00
4.50
ssCost,$persq 2:12
3:12
4:12
5:12
1.50
2.00
20 30 40 50 60 70
Span, f t
Tru
D i F t I t i T C t
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Desi n Fea tures Im ac tin Truss Cost
Regard ing truss spac ing in most c ases,Truss Cost vs. Spacing"
nc truss spa c ng s t e most c osteffec tive, espec ia lly when designingtruss systems with slopes less than 3 on
, ,
3.50
4.00
e
rsq
ft
2:12
. e eng o over ang c an a sop lay a role in the c ost of the trusssystem. As overha ngs reac h 3 feet,2.00
2.50
3.00
Truss
Cost,$
4:12
5:12
6:12
dramatically.
.
2 4 6
Truss Spacing, f t
Truss Cost vs. Overhang Size
Variable Pitch 10" Heel 20 ft S an
4.20
4.60
5.00
5.40
per
sqft
2:12
3:12
1
1.80
2.20
2.60
3.00
3.40
.
TrussCost,$
4:12
5:12
6:12
.
0 1 2 3 4 5
Overhang Length, f t
Desi n Fea tures Im ac tin Truss Cost
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Desi n Fea tures Im ac tin Truss Cost
Concerning the d ebate of Truss Cost vs. SpanVariable Pitch, No Interior Bearings
w e er or no o a n ernabea rings, one c an see that thec ost of ad d ing one bea ring
c an more than a for itself5.00
5.50
6.00
e
rsq
ft
2:12
c omparing the overa ll c ost ofthe truss system. For instanc e, atruss with a c lea r span of 70 3.00
3.50
4.00
4.50
TrussCost,$
4:12
5:12
6:12
c ost approximately $4.60.
2.50
50 60 70
Span, ft
Truss Cost vs. Span
Variable Pitch One Interior Bearin
2.70
2.90
3.10
3.30
ersqft
2:12
By add ing one interna lbea ring, the c ost of the
same truss d rops to less tha n
1.70
1.90
2.10
2.30
2.50
Truss
Cost,$p
4:12
5:12
6:12
. .Just bec ause LGSTs c anspan 80+ feet, it isn t a lwaysthe b est op tion.
1.50
50 60 70
Span, ft
Desi n Fea tures Im ac tin Truss Cost
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Desi n Fea tures Im ac tin Truss Cost
Lon overha n s c a n a d dTruss Material Cost vs. Wind Speed
4:12 Pitch, 40 ft Span, No Overhang
sub sta ntia l costs, espec ia lly in highwind load zones. It is interesting to
note tha t in either c ase, the Ma in
4
4.5
r
sqft
Wind Forc e design method is lessc ostly tha n d esigning usingc omp onents and c ladd ing.2.5
3
3.5
TrussCost,$p
MWFRS
C&C
2
110 130 150
Wind Speed, mph
Truss Material Cost vs. Wind Speed
4:12 Pitch, 40 ft Span, 3 ft Overhang
5
5.5
6
6.5
t,$
persqft
3
3.5
4
4.5
ussMaterialCos
MWFRS
C&C
2
2.5
110 130 150
Wind Speed, mph
T
Desi n Fea tures Im ac tin Truss Cost
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Desi n Fea tures Im ac tin Truss Cost
little c hange to the overa ll design of the struc ture. Looking a tthis examp le, the truss on the left p rovides the same inte rior
slightly higher exterior slope. By add ing some spac e w ithin thetruss, loads are a b le to be d istributed muc h more effic iently. Thistruss a lso erforms muc h better, a llow in the build in muc h lessdeflec tion in a ll d irec tions.
Truss Cost = $583.00 Truss Cost = $748.00
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Environmenta l Benefits of LGST
L E E D Certific a tion with LGST
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L.E.E.D. Certific a tion with LGST
g gauge s ee russes a re exce en p ro uc s or use owar
ac hieving c ertific a tion through g reen build ing ra ting p rog rams
suc h a s LEED. Bec ause light gauge steel produc ts a re up to
100% rec yc led and rec yc lab le, they help to inc rea se the
c hanc e o f rec eiving Ma teria l and Resourc e Cred its. The
number and c a tegory of c red its tha t steel trusses helps in
c ontributing to varies dep end ing on the struc ture o f the ra ting
system being app lied . Another potentia l a rea of c ontribution
inc lude re iona l ma teria l rod uc tion and fab ric a tion in rela tion
to the jobsite depend ing on loc a tion. Other susta inab le
advanta ges c ould be rea lized through the use of steel trusses,
system expert.
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Fabrication
Fabric a tion Guidelines
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Fabric a tion Guidelines
Now we are o in to o into more de th about the advanta esof fac tory fab ric a ted LGSTs. Trusses c an be built and sta ged inc onjunc tion with the sc hedule of the rest of the p rojec t. Trusses
c an be d elivered in sta es as the are needed for erec tion.Fac tory built trusses c an be built to exac t d esign p arameters.Bec ause o f the fac tory setting , supervisors c an manage a ndc ontrol multip le p rojec ts within the fac tory, c ontrasted to anoc c asiona l jobsite visit to c hec k qua lity of work. In add ition, those
who are build ing trusses a re truly Truss Professiona ls. It s wha tthey do. They aren t build ing trusses one d ay and hanging d rywa llthe next. Jig assemblies a re utilized in fac tories to be sure tha t thelast truss in a run matc hes a ll other trusses in the same run. Qua lity
is further enha nc ed due to a c ontrolled environment. On theo s te , qua ty may s p as a resu t o e ements. o rtcutsmay be used when tempera tures d rop or when ra in sta rts to fa ll.There a re a lso servic es being developed tha t c an p rovide thirdpar y qua y gu e nes.
Assembl Methods for LGST
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Assembl Methods for LGST
Uni-Strut i s
Laser set-up
an ry a es
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Shipping
LGSTShi in Basic s
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LGST Shi in Basic s
.50 foot ma ximum leng th and 8 to 10 foot ma ximum w id thwithout permits and esc orts. Trusses up to 80 feet long and 20
feet ta ll ca n be shi ed with s ec ia l ac c ommoda tions.However, p iggy bac king & sp lit trusses are more c ommon.Some fabric a tors will ship vertic a lly with a low tra iler when
ossib le. Wood truss roll off tra ilers c an be used when trussesare adeq uately p rotec ted from da ma ge. Coord inationbetween fabric a tor and job site for p roper sequenc ing is vita l.
LGSTShi in Tec hni ues
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LGST Shi in Tec hni ues
These pho tos illustra tesevera l examples of trusses
shipped c orrec tly.
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Hoisting and Insta lla tion
Insta lla tion Fund amenta ls
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o s ng an ns a a on are c r c a e emen s o e suc cess oLGSTs. With p roper p rec autions ta ken, insta lla tion should besmoo th and uneventful.
Insta lla tion Fund amenta ls
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ne grea resourc e or e russind ustry is The Field Insta llationGuild for Cold-Formed Steel Roof
.ava ilab le through the LGSEA, ad ivision o f the Steel Framing
.
www.steelframingalliance.comIt is a grea t resourc e for manyelements of truss insta lla tion, suc has permanent truss b rac ing .
Hoistin
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ex o rac ng, s s per aps e ey o suc c ess u ns a a on.There a re so many wa ys to do it wrong, and only a c ouple ofways to do it right.
...
Hoistin
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THERIGHT
A spreaderbar and
n exper ence ns a er
Pre-assemblies
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Pre-assemblies a re a nother good op tion to c onsider whenp lanning the truss insta ll. Depend ing on ava ilab le spac e, thisop tion makes a lot of sense, a llowing workers to sta y c lose to the
groun ns ea o wor ng rom ve s o res up . nce e russesare erec ted , b rac ed and sometimes dec ked , the entire roof islifted (or flown) into p lac e. This a lso a llows c rane t ime to be
to save money.
A Grea t Idea for
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Tall build in s Unusua l site c ond itions Job sites with a mple spac e
When c rane time is c ostly When t ime is of the essenc e
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Comparing LGST Proposa ls
Com arin Pro osa ls
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ese var ous cons era ons can ecome very con usng w enthe truss c ustomer has to c ompare and c ontrast five to tend ifferent truss pac kages. Eac h truss sup p lier will p rovide d ifferent
p iec es of the pa c kage. Come b id d ay, it bec omes veryc hallenging to d etermine the b est pac kage d ea l.
Com arin Pro osa ls
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,proliferation in the number of truss fabricators
Barriers to entr a re low non-c ap ita l intensive limited rea l esta te requirements low skilled labor
n c er a n a reas, eng neers arc ec s s a ow ng o s e
fabrication Third party software ava ilab le for simp le truss ana lysis The result c an be multip le b ids on same projec t
A rec ent large p rojec t in TN attrac ted 12 truss b ids
Com arin Pro osa ls
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t so many potent a truss b idders, how is
Com arin Pro osa ls
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what elements make up a
c om lete truss s stem
are not c omparingapples to oranges
Com arin Pro osa ls
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c omp e e ys em mus nc u e...
Properly designed trusses
- - Truss-to-struc ture c onnec tions Insta lla tion b rac ing Let s look a t eac h item in more d eta il.
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Properly Designed Trusses
Pro erl Desi ned Trusses
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e r eac russ s esgne correc y, e sys em mus edesigned to work as a whole.
En ineerin DrawinEn ineerin DrawinJob Name
Number of plies
Job Name
Quantity of trusses
There are a lot of elements that go into a correc tly designed truss.
Truss ID
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Truss ID
TrussDimensions
Truss ID
TrussDimensions
Overall
truss
Number ofscrews requiredat each
connection
Trussslope
Indicateslateral web
bracelocations
Overalltrussheight
Trussslope
n ca eslateral web
bracelocations Number of
screws requiredat each
height
HeelTruss Loading
connec on
Heel
Height
HeightTruss LoadingDeflection
InformationTrussSpacing Applicable
FastenerValues
Truss weight
CombinedStress Index
Applicablecode
TrussSpacing
FastenerValuesSteel sections
Stress Index
Bracin Re uirements
e ect on n o
Steel sections
Bracing Requirements
Truss Reactions
Truss Reactions
Individual member
Individual memberforces
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Truss-to-Truss Connec tions
Truss-to-Trussonnec ons
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ese c onnec ons arec ritic a l to the p roperfunc tioning of the truss
Connec tions must sa felytransfer a ll loads into
They must resist up lift asnecessary
truss designer p rovide forthese connec tions
ANSI TPI 95If a LGST provider dec linesto provide these
,
ACCEPT THE PROPOSAL!
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Trust-to-Struc ture Connec tions
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Truss-to-Struc tureonnec ons
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These a re c ritic a l to the properfunc tioning of the truss system
Resisting uplift
nc ors russes o s ruc ure Designer must ac c ount for
bea ring surfac e, atta c hment,
conditions Standard deta ils useful, but
c ritic a l, espec ia lly in high windzones
engineer
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Truss Brac ing
The Card ina l Rules of Truss Brac in
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qua y mp or an o e russes emse ves s e russ rac ng,both insta lla tion and perma nent.
ALL truss systems require b rac ing --PERIOD!!
Fa ilure to adhere to Rule # 1 is the primary reasonfor truss
c ollapses (typ ic a lly during insta lla tion)
Rule #3 Disputing Rules # 1 and # 2 d isp lays an absence of
knowled e of how truss s stems func tion
The Card ina l Rules of Truss Brac in
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Resulta nts for NOTfollowing Rule # 2
Trusses tha t had
bracing
T es of Truss Brac in
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ns a a on rac ng Lac k of insta lla tion brac ing is the reason for virtua lly a ll
roof c ollapses during c onstruc tion
bracing
Provides for web brac ing , shear d iaphragm transfer,
and overa ll roof system sta b ility
Installation Bracin
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ns a a on rac ng s us as e name mp es, rac ng a eepsthe trusses in p lac e d uring insta lla tion. There a re three parts to it,top c hord b rac ing, bottom c hord brac ing, and web brac ing.
. ,used in ea c h loc a tion. It is sa id tha t without d iagona l b rac es, a llthe trusses simp ly fa ll the same d irec tion. Don t forget the
remain in the system and serve as permanent b rac ing.
Guidelines pub lished by LGSEA
Ground b rac ing Top c hord brac ing
Keeps c hords in line rac es c or s rom uc ng Bottom c hord b rac ing
Keeps c hords in line Web p lane b rac ing
Help sta b ilize the entire system p rior to dec king
Field Insta lla tion
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Guide for Cold -Formed Steel Trusses
The Field Insta lla tionGuide for Co ld -Formed
Steel Trusses, p rovidedby the Light Ga ugeSteel Eng ineersAssoc ia tion, goes into
grea t deta il about thebrac ing req uired forrusses.
Permanent Brac in
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ermanen rac ng s a w c rema ns n p ac e a er etrusses are e rec ted . This b rac ing is designed to keep the trussesin p lane a s loads a re a pp lied , p reventing the c hance for out o f
. ,
Permanent Brac in
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e rmanen rac ng
Top Chord
Typic a lly direc t app lied dec k
Could be purlins 24 o.c .
Bottom Chord
Can be ri id ceilin d irec tl a lied
24 o.c . purlins with d rywa ll
Drop c eilings will require user defined spac ing for la tera lbracin
Typic a lly 6 to 8 o.c .
Don t forget the d iagona l b rac ing!
La tera l Brac ing
Be sure webs line up --otherwise, T-b rac ing will be
Diagona ls a re essential
Who ha s responsib ility for Permanentrac ng esgn
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ecause o e un que na ure o eac russ p ro ec , e es wayto assure tha t the brac ing is hand led c orrec tly is to p rovide apermanent b rac ing design. Ac c ord ing to typic a l p rotoc ol, this
.overa ll build ing design and understand how the build ingc omponents a re to be integra ted . However, bec ause of the
with p roprieta ry LGSTs, the job may be best a ddressed by the
truss eng ineer. Regard less of who provides it, be sure the.
Brac in Deta ils
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e o ow ng a re examp es o an eng neere rac ng esgn.One shows the p ermanent web b rac ing required , the other is asheet o f add itiona l deta ils that must be a pa rt of the b rac ing
.
Bra c in Desi n
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Bra c in Desi n
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Light Gauge Steel Trusses
What Will Drive the Use of LGST
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nc rea sng y s r ng en re c o es Build ing designers love the fea tures & b enefits More c ost effec tive tha n trad itiona l materia ls
, ,accessories Arc hitec ts and engineers looking for ways to get the job done
The trend for p re-fabric a ted c omponents c ontinues to inc rease
In Conc lusion
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oranges by
portion o f the truss systemPut it in the spec ific a tionDon t forget to identify responsib ility for other anc illa ry
Shear b loc king and transfer framing, bent meta l
for dec k support, fasc ia materia l, and over-framing Understa nd ing truss nomenc la ture Tho roug hlyevalua ting proposa ls and b ids
Don t ust rab the lowest number and run with it Being c autious of the term Value Eng ineering Communicating!!!
In Conc lusion
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For Non-Combustib leCommerc ial/ Institutiona lConstruction...
Light Gauge Stee lTrusses are a great
alternative...
Summar
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e es gn ro ess ona s ou now e a e o:
Explain why Light Gauge Steel Trusses a re a Good Alterna tive
Exp la in a pp lic a tions for Proprieta ry LGST List and desc ribe Case Stud ies
Desc ribe the design proc ess for Fac tory-built LGST
Exp la in: Fabric a tion, Pac kaging , Shipp ing , & Insta lla tion of-
Compare and c ontrast a n LGST p roposa ls and exp la in whatmakes a c omp lete truss system
Links to more information a bout LGST
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g a uge ee ng neers ssoc a on :www.lgsea.com
. .
Aegis Meta l Framing www.aegismetalframing.com
Course Sponsor
AEGIS Metal Framing
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g
14515 N Outer 40 DriveSuite110
Chesterfield, MO 63017
Light Gauge Steel TrussesThe Specification, Design Manufacturing and
314-851-2234
E-mailjaltman@aegismeta lframing .com
Web
www.aegismetalframing.com
Course Numb er
Please note: you will need to c omplete the c onc lusion quiz online atronblank.com to rece ive credit
An AIA Continuing Educ a tion ProgramCred it fo r this course is 1 AIA/ CES HSW Learning Unit