PRODUCT FEATURES //INSTALLATION MANUAL
ALUMINIUMBUILDINGSHEETS.
ALUMINIUM. // METAL OF THE FUTURE.
INFINITEPOSSIBILITIES.
Company
Address
: Aluminium Company of Malaysia Bhd.
: No. 3 Persiaran Waja
Bukit Raja Industrial Estate, Klang
41050 Selangor, Malaysia
Phone
Fax
Web
: +603 3346 6262
: +603 3341 2793
: www.alcom.com.my
ALUMINIUM.
INFINITEPOSSIBILITIES.Our vision and company values reflect ourcapabilities and aspirations, and the uniqueproperties of the products that we make. Ourfuture lies in continually reinforcing the valueproposition we offer to our customers and thecommitments we've made to all ourstakeholders including the environment andthe communities in which we operate. We willbuild on our legacy and continue to createhigh-value products to make the world lighter,brighter and better.
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INTRODUCTION - ALCOM BUILDING SHEETS
PRODUCT FEATURES - 7P/COMSPAN/ALRIB
PRODUCT INFORMATION - 7P
PRODUCT INFORMATION - COMSPAN
PRODUCT INFORMATION - ALRIB
DESIGN INFORMATION & INSTALLATION PROCEDURE
INSTALLATION
ROOF FLASHINGS
SITE NOTES
SPECIFICATIONS FOR TENDERING PURPOSES
TABLE OFCONTENTS.
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FORM&FUNCTIONALITY.
COOL.LONG-LIFE.RUST-FREE.
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AN INTRODUCTIONTO ALCOM'SBUILDING SHEETS.ALCOM Building Sheets has been in the market sincethe 1970s, under its own brands such as ALCOM 7P,Comspan and Alrib in coastal, heavy industrialenvironments and agricultural sectors.
ALCOM's Stucco Embossed and Polyester ColorbakedBuilding Sheets offer you a wide range to choose from.With a weight that is 2.9 times lighter than steel, it doesnot tax your load design factor for your roofing projects.No other Building Sheet can offer you the coolness andlife-long durability that aluminium provides.
Laid out in this catalogue are details of our variousbuilding sheets, their features, technical details as wellas installation procedures. For further details, ourBuilding Sheets Department will be more than happyto discuss your needs with you.
PRODUCTFEATURES.ALUMINIUM - METAL OF THE FUTURE
ALUMINIUMIN BUILDING
Aluminium with its inherentcharacteristics of corrosion-resistance, maintenance freerecyclability, light weight, durabilityand high specific strength byalloying with other elements makingit one of the most versatile materialwidely used in every industry. Itsadded characteristics of high heatreflectivity and low thermalemissivity in particular, make it themost suitable material for roofingsheets.
Aluminium's best knowncharacteristics is its light weight.With a density about one-third thatof steel and one-fifth that ofasbestos cement, it is the lightestmetal commonly used in building.Compared to steel and asbestos,lighter aluminium enables significantsavings in the cost of structuralsupports, erection time andmanpower.
WEIGHT
Alcom Building Sheets are producedfrom an alloy containing a smallpercentage of magnesium andmanganese of H8 temper andhaving a minimum ultimate tensilestrength of 185 Mpa.
STRENGTH
Although aluminium has twice thecoefficient of expansion of steel (24 x10-6 vs 12 x 10-6), the effect of this isoften over estimated. Usuallyaluminium roofing sheet is fixed to asteel structure where under thesame thermal influence expandsand contracts. The combination ofthese factors results in low relativeexpansion between the aluminiumroofing sheet and the steel structure.In practice the theoretical expansionof an aluminium roof relative to thesteel structure on which it is fixed isreduced by up to 50%.
THERMALEXPANSION
CONDENSATION Condensation occurs on theunderside of all metal roof when theroof metal temperature falls belowthe dew point of humid air heldagainst the underside of the roof.Control of under condensation canbe effected through the reduction ofthe moisture content of the air underthe roof by one of the followingprocedures: (1) providing ampleventilation of the building or of theceiling space, if any; (2) laying aninsulation blanket with aluminiumfoil laminated to the underside, overthe purling before laying the roof.
Classified as a non-combustiblematerial for both coated and bare.Certified compliance with BS476 Part6 (Fire Propagation) and BS476 Part7 (Surface Spread of flame) Class Iby SIRIM and certified as Class Omaterial by Fire and RescueDepartment of Malaysia.
FIRERESISTANCE
Rain can cause noise problems onall sheet metal roofs. Noise levelscan be considerably reduced by theapplication to the under side of theroofing sheet.
ACCOUSTIC
Lengths of up 20.0m are producedand transported to site by trailersaccording to customer'srequirements. For lengths producedover 20m, this will be subject totransport regulations of the country.
SHEETLENGTHS
Heat is transferred by conduction,convention and radiation. Up to 95%of heat transfer through a roof in ahot day is by radiation. Aluminiumhas a very high reflectivity ofapproximately 70% to 90%,depending on degree of oxidation ofsurface. Installations havedemonstrated that thermal radiationin a hot day under an uninsulatedaluminium roof is markedly less thanother roof decks, resulting in greaterpersonal comfort.
HEATTRANSFER
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ALUMINIUM (WEATHERED)
CEMENT
GALVANISED STEEL (NEW-WEATHERED)
0.74
0.34
0.34-0.11
REFLECTIVITYProportion of each unit of totalincident radiant heat reflectedfrom exposed surface.
ALUMINIUM (WEATHERED)
CEMENT
GALVANISED STEEL (NEW-WEATHERED)
0.26
0.66
0.66-0.89
ABSORTIVITYProportion of each unit ofincident heat absorbed byexposed surface.
ALUMINIUM (WEATHERED)
CEMENT
GALVANISED STEEL (NEW-WEATHERED)
0.11
0.28-0.42
0.99
EM I SS IV I T YProportion of absorbedheat emitted by radiationfrom surface.
THE COOLFACTOR.
Buildings constructedwith aluminium buildingsheets are always cooler,offer lower energy billsand maximize personalcomfort.
ALUMINIUM ZINC/ALUMINUMALLOY-COATED STEEL TEMPERATUREDIFFERENCE
45
40
35
30
25
20
15
10
5
0
6
5
4
3
2
1
0
ROOMTEMPERA
TURE
(OC)
TEMPERA
TURE
DIFFERENCE
(OC)
00:01:3 1
00:51:3 1
01:41:3 1
02:31:3 1
03:21:3 1
04:11:3 1
05:01:3 1
05:51:3 1
06:41:3 1
07:31:3 1
08:21:3 1
09:11:3 1
10:01:3 1
10:51:3 1
11:41:3 1
12:31:3 1
13:21:3 1
14:11:3 1
15:01:3 1
15:51:3 1
16:41:3 1
17:31:3 1
18:21:3 1
19:11:3 1
20:01:3 1
20:51:3 1
21:41:3 1
22:31:3 1
23:21:3 1
TIME (24 HR)
TEMPERATURE CHART IN 24 HOURS
The natural finish on an aluminiumsurface reflects at least 80% of radiantHeat that falls upon it, even whenlightly covered with dust or slightlysoiled.
This high reflectivity ensures thatmaximum heat is reflected andconsequently aluminium-cladbuildings tend to remain cool undertropical sunlight.
This is of major importance in tropicalenvironments where in hightemperatures a single sheet ofaluminium roofing gives an internalbuilding temperature of approximately10% lower than galvanised steel.
OVERALLSHEETWIDTH
952mm
EFFECTIVECOVERWIDTH
889mm
DEPTHOFTROUGH
38mm
7P is a trapezoidal profile suitable for use in factories andwarehouses and in rubber, oil palm, cocoa and rice mills.This sheet is available in an attractive range of colours andcan be supplied in continuous long lengths specified bycustomers for projects where joints are minimised. Theversatility of this profile is due to its strength, water carryingcapacity, fixing economy and cave closures features. It iswidely used for roofing and can be reversed to provide abold wall effect.
PROFILE 7P.
Notes:* The spacing is determined based on a point load of 130kg applied at mid spanwith maximum allowable bending stress of 76N/mm2.** The spacing is determined by practical consideration of ensuring that the sidelapping is adequately held down.
889mm
127mm pitch
19mm 57mm
38mm
0.500.550.700.90
1.9122.1032.6773.442
517.6470.4369.5287.4
3o
(1 in 20)1.371.502.002.50
1.502.002.503.00
Thickness(mm)
EffectiveWeight(kg/m2)
EffectiveCover(m2/MT)
MinimumRecommendedPitch
RecommendedPurlin Spacing(m)*
Wall GirtSpacing(m)**
0.500.550.700.90
0.660 x 103
0.726 x 103
0.924 x 103
1.188 x 103
5.90 x 103
6.49 x 103
8.23 x 103
10.54 x 103
139.1 x 103
153.0 x 103
194.8 x 103
250.4 x 103
Thickness(mm)
Section Properties Per Metre Width
Area(mm2)
Modulus(mm2)
Moment ofInertia (mm2)
0.500.550.700.90
150150200300
Max Eaves OverhangUnsupported
Thickness mm
5o - 10o
10o - 15o
Above 15o
300250200
End Laps
RoofPitch
End LapsLength(mm)
Maximum Allowable Distributed Load/Deflection
0.50
0.55
0.70
0.90
Load (KN/m2)Deflection Under Above Load (mm)Load (KN/m2)Deflection Under Above Load (mm)Load (KN/m2)Deflection Under Above Load (mm)Load (KN/m2)Deflection Under Above Load (mm)
1.372.406.82.606.73.336.74.206.8
1.502.008.12.198.22.788.23.568.0
1.751.5011.31.6111.22.0411.72.6211.1
2.001.1014.21.2314.61.5614.52.0014.5
2.250.9018.50.9718.41.2418.51.5818.3
2.500.7021.90.7922.81.0022.71.2822.6
Thickness Multi-Span Purlin Spacing (m)
0.50
0.55
0.70
0.90
Load (KN/m2)Deflection Under Above Load (mm)Load (KN/m2)Deflection Under Above Load (mm)Load (KN/m2)Deflection Under Above Load (mm)Load (KN/m2)Deflection Under Above Load (mm)
1.371.929.22.089.02.669.13.368.9
1.501.6011.01.7510.92.2210.92.8510.9
1.751.2015.31.2914.91.6314.82.1014.8
2.000.8819.10.9819.31.2519.41.6019.3
2.250.7225.00.7824.70.9924.61.2624.3
2.500.5227.80.5827.80.7327.80.9427.8
Thickness Single-Span Purlin Spacing (m)
GEOMETRICPROPERTIES.
LOAD TABLE - 7P.
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Note:The maximum allowable distributed load is determined based on a maximumallowable bending stress of 76 N/mm2 except values in grey boxes where thelimiting criteria is deflection (span/90)
OVERALLSHEETWIDTH
950mm
EFFECTIVECOVERWIDTH
864mm
DEPTHOFTROUGH
52mm
This profile was designed specifically to provide a widespanning capability and a distinctive appearance to providefrequent roof traffic. The large robust ribs and exceptionalwater carrying capacity of this profile make it ideal for largehigh performance roofs such as power-stations, industrial orcommercial buildings and used on walls where a strongvisual effect is required. This profile has been chosen forSydney's Aquatic Stadium, a venue for the 2000 OlympicGames.
COMSPAN.
864mm
216mm
52mm
114mm 30mm
Notes:1. On minimum slope, care must be taken to ensure that purlin sag or misalignmentdoes not result in water ponding on the roof, particularly if end laps are used.2. The spacing is determined basing on a point lead of 130kg applied at mid-spanwith maximum allowable bending stress of 76N/mm2.3. The spacing is determined by practical consideration of ensuring that the sidelapping is adequately held down.
0.700.90
2.6143.343
384.56299.10
2o
(1 in 29)2.02.5
2.53.0
Thickness(mm)
EffectiveWeight(kg/m2)
EffectiveCover(m2/MT)
Minimum1
RecommendedPitch
Recommended2
Purlin Spacing(m)*
Wall Girt3
Spacing(m)**
0.700.90
8.911.4
306393
Thickness(mm)
Section Properties Per Metre Width
Thickness(x 1000 mm2)
Moment of Inertia(x 1000 mm2)
0.700.90
200300
Max Eaves OverhangUnsupported
Thickness mm
2o - 10o
10o - 15o
Above 15o
300250200
End Laps
RoofPitch
End LapsLength(mm)
Maximum Allowable Distributed Load/Deflection
0.70
0.90
Load (KN/m2)Deflection Under Above Load (mm)Load (KN/m2)Deflection Under Above Load (mm)
1.254.333.915.543.90
1.503.015.633.855.62
1.752.217.662.837.64
2.001.6910.012.179.98
2.251.3412.671.7112.64
2.501.0815.641.3915.60
Thickness Multi-Span Purlin Spacing (m)
0.70
0.90
Load (KN/m2)Deflection Under Above Load (mm)Load (KN/m2)Deflection Under Above Load (mm)
1.253.465.214.445.20
1.502.407.513.087.49
1.751.7710.222.2610.19
2.001.3513.351.7313.31
2.251.0716.891.3716.85
2.500.8720.861.1120.80
Thickness Single-Span Purlin Spacing (m)
GEOMETRICPROPERTIES.
LOAD TABLE - COMSPAN.
POSITIVEFIXING.
Note:The maximum allowable distributed load is determined based on a maximumallowable bending stress of 76 N/mm2.
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OVERALLSHEETWIDTH
960mm
EFFECTIVECOVERWIDTH
914mm
DEPTHOFTROUGH
19mm
The wide (914mm) cover width of Alrib, in conjunction withits symmetrical profile, provides a roofing sheet which canbe used effectively on walls as well. A double capillary drainin the rib overlap ensures weather security. On top ofproviding a neat, balanced appearance on buildings, thisprofile is also effectively used as insulation jacketing inpower stations and chemical processing plants.
ALRIB.
19mm
41mm 19mm 19mm50.5mm
19mm
228.5mm pitch
Notes:Alrib, if used for roofing, should be limited to narrow purlin spacing and"light" duty purposes.* The spacing is determined based on a point load of 68kg applied at mid spanwith maximum allowable bending stress of 76N/mm2.** The spacing is determined by practical consideration of ensuring that the sidelapping is adequately held down.
0.550.700.90
1.7512.2282.866
580.8456.3354.9
Above 5o 0.81.001.30
1.61.82.0
Thickness(mm)
EffectiveWeight(kg/m2)
EffectiveCover(m2/MT)
MinimumRecommendedPitch
RecommendedPurlin Spacing(m)*
Wall GirtSpacing(m)**
0.550.700.90
0.605 x 103
0.770 x 103
0.990 x 103
1.42 x 103
1.80 x 103
2.30 x 103
22.6 x 103
28.8 x 103
37.0 x 103
Thickness(mm)
Section Properties Per Metre Width
Area(mm2)
Modulus(mm2)
Moment ofInertia (mm2)
0.550.700.90
150200300
Max Eaves OverhangUnsupported
Thickness mm
7.5o - 15o
Above 15o
300250
End Laps
RoofPitch
End LapsLength(mm)
Maximum Allowable Distributed Load/Deflection
0.55
0.70
0.90
Load (KN/m2)Deflection Under Above Load (mm)Load (KN/m2)Deflection Under Above Load (mm)Load (KN/m2)Deflection Under Above Load (mm)
1.001.085.301.375.301.755.30
1.250.698.300.888.301.128.20
1.500.4812.00.6112.00.7811.9
Thickness Multi-Span Purlin Spacing (m)
0.55
0.70
0.90
Load (KN/m2)Deflection Under Above Load (mm)Load (KN/m2)Deflection Under Above Load (mm)Load (KN/m2)Deflection Under Above Load (mm)
1.000.867.21.107.21.407.1
1.250.5511.20.7011.20.9011.2
1.500.3816.10.4916.30.6216.0
Thickness Single-Span Purlin Spacing (m)
GEOMETRICPROPERTIES.
LOAD TABLE - ALRIB.
12
Note:The maximum allowable distributed load is determined based on a maximumallowable bending stress of 76 N/mm2.
The quantity and length of sheets should not be determined fromdrawings, but from actual measurements of the structure makingdue allowance for the squareness of the structure. Where sheetsare to be end-lapped, allow the extra length which varies. (referpages 7, 9 & 11) according to the roof pitch. An additional 50mm isto be allowed for gutter overhang. To determine the thickness ofthe sheet and the respective recommended purlin spacing, pleaserefer to pages 8, 10 & 12.
ORDERING SHEETS.
DESIGNINFORMATIONANDINSTALLATIONPROCEDURE.
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PrevailingWind
CommenceInstallationthis end
41
2
3
Sheeting Progress
Prevailing Wing
Configuration ofthe four-ply laps.The corner of Sheet2 has to be lifted sothat Sheet 3 can betucked underneath.
PREPARATION.
Before commencing to lay the sheet,consideration should be given to theinstallation of gutter and eave flashing,insulation and the location of roofpenetrations such as vents, skylights, etc. Ifinsulation is to be laid on wire mesh, themesh should be laid first with the gutterand eave flashing following to secure thewire at the eave. Insulation should be laidwith the roofing to avoid the possibility ofrain wetting insulation.
PURLIN ISOLATION.
In marine, moist aggresive environments,the face of steel, copper impregnatedtimber, purlins or girts, against that whichthe sheeting is fastened, is to be paintedwith chromate based primers, bituminouspaint or similar.
SHEET INSTALLATION.
Customary practice is to lay out an area ofsheet and secure each sheet with a crestfastener at the centre of the ends of themiddle, at the same time checking theprofile with a scalloped ridge flashing toavoid profile spread. The area of sheet laidout should be no more than that which canbe fully fixed within the day of laying. Whenthe area of sheet has been laid, install sidelap fasteners and then the balance of crestfasteners.
Wherever possible commence laying thesheet, farthest from the expected directionof the heaviest rain or wind and from theeaves toward the ridge. The top end of thesheet should be not more than 100m fromthe ridge or fascia line and the bottom endshould extend 50mm into the gutter. Theridge and eave ends are to have the pansupturned and downturned respectively.End forming tools are available for thispurpose.
Roof slopes greater than 25o require sidelap sealing, with a continuous run ofsilicone sealant.
SHEET CUTTING DRILLING.
Aluminium is best cut with lubricated finetooth circular saw. All holes must be drilledand not puncture. Care nuts be taken toavoid distortion of the short profile.
DISSIMILAR MATERIALS.
Under no circumstances should copper,brass, or copper alloys be placed in contactwith aluminium or water run off from thesemetals discharge on to aluminium sheet.
Silicone sealants used with aluminiumsheeting must be neutral cure. Care mustbe taken to avoid contact with buildingmaterials such as unseasoned orchemically treated timber, lime cement,concrete, mortar or plaster duringconstruction and to provide impermeablebarriers against long term contact.
In marine, moist or aggressiveenvironments the face of steel orchemically impregnated timber purlins,against which the sheeting is fastened, is tobe painted with chromate based primers,bituminous paint or coated with Norton 550adhesive P.V.C. tape.
Under severe marine and/or aggressiveindustrial environments Denso tape orclosed cell polyrthylene tape should beused to completely fill the sheet/structureinterface to avoid moisture retention bycapillary action. Alcorn will provideapplication advice in such situations
INSTALLATIONINFORMATION.
END LAPS.
When end laps are used the lower sheetsare laid first, without being fastened to thepurlin at the top of the sheet slope. Thenext sheet up the roof slope is then laid andis first temporarily secured and then fixedfrom the upper end towards the lower. Thedetail of overlapping is as per diagram.
L
Fall
WALL CLADDING.
Wherever possible commence fixingfarthest from the expected direction of theheaviest wind or rain. Where more than onelength is used for the wall height, anoverlap of 100m should be allowed at a girtwith the upper sheet overlapping the lowersheet.
SIDE LAPS.
Sheet edges must be fixed together at sidelaps wherever necessary. The side lapfastener is fixed through the centre of therib crest over each purlin first and thenbetween the purlins. During the fixing,ensure that the overlapping rib is pressedfirmly against the underlap rib.
Radius ofCurvature
Arc LengthTangent PointAlcom 7P Aluminium Roofing
Sheet may be curved over theridge of a low pitched roofprovided that the radius ofcurvature is not less than 18m.This method of installation willavoid the use of standard ridgeflashings and simplify roofinstallation procedures.
CURVED RIDGING - LOW PITCHED ROOFS.
A central ridge plate should not be used in this type of application but if it is considerednecessary, from a construction point of view, the ridge plate should be positioned 50mmbelow the underside of the curved roof sheeting.
Purlins should be placed symmetrically about the ridge centre-line and at each tangentpoint.
The module of the sheet and the fixing positions should be marked along the purlinsbefore laying commences. This practice will provide a check against spreading of theprofiles during fixing and will make sheet laying faster. Sheeting must commence square tothe purlins.
Roof PitchRoof GradientArc Length (m)at 18m radius
11:570.63
21:291.26
31:191.88
41:142.51
51:113.14
61:103.77
81:75.03
91:65.65
101:5.76.28
FASTENING OF PURLINS TO MAIN STRUCTURE.
Aluminium has less weight of its own to resist wind suction than some other roofingmaterials. Therefore, in exposed positions and areas of the country where high winds areexperienced, it is essential that extra care is taken to ensure that all purlins are securelyfixed to the building. In particular the anchorage of the eaves purlin must be able towithstand any anticipated wind velocity.
The general practice is to lay out an area of sheet and secure each sheet with a crestfastener at the central of the ends and middle at the same time checking the profilewith a scalloped ridge flashing to avoid profile spread. The area of sheet laid outshould be no more than that which can be fully fixed within tha day of laying. Whenthe area of sheet has been laid, install crest fasteners and then the side lap fasteners.
INSTALLATION.
16
FIXING - PURLIN FASTENER FOR ROOFINGS.
A. Crest Fixing Pattern (Recommended for All Roofing)
Steel Purlins - Hex head fastener no.12 x 57mm screw with pre-assembled 22mm O.D.neoprene bonded washer for crest fixing through the roofing sheets onto steel purlins.
Timber Purlins - Hex head no.12 x 65mm self-drilling woodscrew with pre-assembled22mm O.D. neoprene bonded washer for crest fixing through the roofing sheets onto steelpurlins.
Stitching screws when required Stitching screws when required
FIXING - ALRIB.
A. Crest Fixing Pattern (Recommended for Roofing with low load requirements)
B. Valley Fixing Pattern (Recommended for Wall Cladding)
B. Valley fixing Pattern (Recommended for Wall Cladding)
Steel Purlins - Hex head fastener no.12 x 25mm screw with pre-assembled 16mm O.D.neoprene bonded washer for valley fixing through the roofing sheets onto steel girt.
Timber Purlins - Hex head no.12 x 65mm woodscrew with pre-assembled 16mm O.D.neoprene bonded washer for valley fixing through the roofing sheets onto timber girt.
Stitching screws when required
POSITIVE FIX SYSTEM.
ROOF FIXING TheALCOM Positive FixSystem provides forthermal expansion onthe roofing sheet by"hard" fixing at the topof the sheet slopewith " expansion"fixing being used toaccommodateexpansion towardsthe lower end of thesheet slope.
HARD FIX "Hard"fixing is used for thefirst 6 metres fromthe ridge or skillionhead and consists ofdrilling the self-tapping screwthrough the rib andpurlin, opening therib crest hole to6mm diameter.
EXPANSION FIX "Expansion" fixing isused for the remainder of the sheetlength where by the hole in the rib crestis slotted using a custom tool. The heavyformed aluminium washer then providesprotection while allowing for thermalexpansion.
Ceramic coated steel self-drilling fastener.
Sealing washer provides"first line" defence againstwater.
Heavy formed washerbacks up the profile rightwhere it is needed, samegrade alloy as the roofingsheet.
EDPM/Teflon washer sealsover the thermalmovement range andallows quiet, abrasion-freemovement of the roofing.
Slot allows thermalmovement to occurwithout strain on theroofing system.
All Alcom roofing profilesare roll formed from a highstrength aluminium alloy.
Squareness - Check the roof or wall structure for squareness before commencing to laysheet. Sheet must be laid square to the ridge wherever practical. Out-of-square whichexceeds 100mm over the sheet length should be corrected by trimming the edge of thesheet laid against the out-of-square edge. Any sag of purlins should be corrected beforecommencement particularly on low pitch roofs to avoid water "ponding".
Fastening - The Alcom Positive Fix System consists of 3 components assembled as shown.The self-tapping screw may be driven with an electric screw gun at a maximum speed of300 R.P.M. Note that for expansion, fixing a rubber washer with an elongated hole and ateflon facing on one side is used. This washer must be installed with the teflon side facingUP towards the head of the screw. For both types of fastening, the screw should bescrewed down until it presses on the washer with medium pressure. Under nocircumstances should the screw be overtightened to the point where the formed washeror the bonded washer under the screw head commence to distort.
The correct installation of flashings to seal the roof perimeters orpenetration is essential to the security weather tightness of theroof. Consideration has to be given to movement between the roofand building walls and the length expansion of flashings.
Alcom supplies a range of custom-made flashings which areprovided to the same metal specifications as the roofing sheetmade flashings are required the metal should be to the followingspecifications.
Finish: Stucco Embossed / Coated
RIDGE CAPPING
EAVES FLASHING
APRON FLASHING
HIGH END FLASHING
VALLEY GUTTER
GABLE END FLASHING
ROOFFLASHINGS.
18
SHEETS TURN-UP.
Valley of 7p sheetsmust be turned up atthe high end of the roofsheets to ensure waterthat is wind-drivenbeneath the flashingsdo not drain into thebuilding.
Turn up operation ofComspan sheets at thevalley ensure water isnot drained into thebuilding.
Turn up operation ofAlrib sheets at thevalley ensure water isnot drained into thebuilding.
RIDGE FLASHING. 0.70mm x 2.44mm long
Ridge flashing fixed to flashing closure at everyalternate rib crest with No.9 x 25mm screws
Flashing closure use No.12 x 57mm screws at everyalternate rib crest
Valley of sheet turned up 38mm to form waterstop
CORNER FLASHING. 0.70mm x 2.44m long
Steel purlin
Use No.12 x 25mm screws at every alternate valley
Corner flashing fixed to sheet with No.9 x 25mm screwsat maximum 600mm centres
FASCIA FLASHING. 0.70mm x 2.44m long
0.70mm x 2.44m long
Fascia flashing fixed to flashing closure at everyalternate rib crest with No.9 x 25mm screws
Valley to sheet turned up 38mm to form waterstop
Use No.12 x 57mm wood screw at every rib crest
Flashing closure
Fascia boardSteel purlin
BARGE FLASHING.
Ridge flashing fixed to flashing closure at everyalternate rib crest with No.9 x 25mm screws
Valley to sheet turned up 38mm to form waterstop
Flashing closureUse No.12 x 25mm wood screw at maximum 600mm
centres
SKYLIGHTS.
Clear acrylic translucent plastic sheets orfibre glass sheets which are made to profileand width of the roofing sheet arecommonly installed at selected positionsserving as skylights. These translucentsheets are installed such that the top end isoverlapped by the roofing sheet and thebottom end overlap the roofing sheet at thelower end of the fall.
SITE NOTES.
HANDLING & STORAGE.
Alcom Aluminium Roofing Sheets are quality products and consequently, care should betaken in storage and handling.
When received at the site, the sheets should be kept dry and stored under cover untilthey are required. Precaution should be taken to prevent moisture and water being drawnbetween the sheets. This may lead to staining which is unsightly although it is notdetrimental to the material. Sheets that have become wet during transport is to beunpacked immediately and each sheet dried thoroughly on both sides before restacking.
Should the Building Sheets be kept in the open, it should be stored in its original packingand to be stacked in an inclined position of minimum 3° with an air space below the stack.
If the original packing has been opened, store the sheets as follows:
Stack the sheet with the bent edges facing downwards in an inclined position ofminimum 3°, with an air space below the sheets and the higher end covered withpolythene sheet. Extend the top sheet 600mm to 900mm towards the higher end and thesecond sheet almost to the floor. The higher end of the pack comprising the third andsubsequent sheet should be well wrapped in polythene sheets across the completewidth and extending 300mm down the length of the pack. (Refer to diagram below)
WALKWAY & NOTICES.
Experience in Malaysia has shown thatworkmen tend to take less precaution withaluminium rather than with asbestos andother roofing materials. Care should betaken therefore, to ensure that access toroofs should be restricted to authorisedpersons carrying out inspection andmaintenance.
Irrespective of the thickness of the sheeting- crawl boards, walkways or roofing laddersshould be provided so as to preventdamage to the roof.
CLEANING UP.
On completion of installation, sweep theroof clean with a soft broom, taking care toremove all steel nails, scraps or copper orlead, fillings, pop rivet stems, muddyfootprints, etc., which are likely to promotestaining or corrosion of the roof surface.
WALKING THE ROOF.
Evenly distribute body weight over thesoles of the feet trying not to concentrateweight on heel or toes. Soft soled shoesshould be worn. Walk on the centre of thesheet when walking along the run of thesheet and along supports when walkingacross the sheet.
Polythene Sheet
Wooden Support
Air Space
WoodWeightsTop Sheets
3o 300mm
600-900mm
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ROOFING.
The following information is provided as ageneral guide to be used for Bills ofQuantities. These statements should beexpanded further where specific siteconditions create exceptionalcircumstances.
The roofing materials used shall be ALCOM7P/ Comspan / Alrib Industrial BuildingSheets of specified thickness of StuccoEmbossed/Polyester Colour-baked finish.Fastening of the roofing sheets shall beaccording to the Manufacturer'sSpecifications unless otherwise stated. Thelength of manufacturer's recommendations.7P Roofing Sheets must be fastened on thesteel purlins with the crest fixing using"Ruspert" ceramic plated fastenerscomplete with 22mm aluminium masterseal bonded washers. Stitching screws forside laps shall be used at all timesregardless of roof profiles. Side lap screwsshall be according to manufacturer'sspecifications.
Flashing shall be fabricated from the samemetal and be fitted, lapped, sealed, andsecured according to the manufacturer'srecommendations. Proper tools shall beused for turn-up and turn-down of theroofing sheets. Notching of transversecappings and flashings shall be carried outin accordance with Manufacturer'sSpecifications.
SHEETING ACCESSORIES.
These shall be of the same quality andfinish as the roofing and wall claddingsheets. They include all fasteners, flashing,sealant, ridge flashing, fascia, cornerflashing, barge flashing and any other itemrequired to complete and ensure watertightness of the roof and wall cladding.
FIXING ACCESSORIES.
The fixing accessories for the roofing andcladding sheets shall be of material asrecommended by Manufacturer. Theseinclude clips, ceramic plated screws, self-tapping fasteners, rivets, studs, washers,bitumen felt washers, neoprene gasketsand other accessories to ensure properfixing roof/cladding.
WATER TIGHTNESS.
The Alcom Approved Roofing Contractorshall be responsible for the water tightnessof the roof and shall make good anydefects arising from incorrect fixingprocedures. Site inspection with theManufacturer will be carried uponcompletion of works.
RAINWATER ITEMS.
Gutters and downpipes shall be inaccordance to the specifications drawn upby the owner.
Note:
The above information are theManufacturer's Recommendations on theapplication of aluminium building sheets. Itis the Owner's responsibility to ensure allStructure and Roof Designs conform to theBuilding By-Laws of Malaysia. Alcom shallnot be held responsible should any claimarises.
STORAGE OF ROOFINGSHEETS.
When the roofing/cladding sheets are notin use immediately after delivery to the site,protection procedures must be undertakento ensure proper storage. Sheets must bestacked clear of ground level andprotected by tarpaulins according to themanufacturer's recommendation. Materialsdamaged before and/or during installationshall be deemed to be replaced at thecontractor's own expense if defects arefound to be due to the negligence of thecontractor.
SPECIFICATIONS FORTENDERING PURPOSES.
ALUMINIUMCOMPANY OFMALAYSIABERHAD.Aluminium Company of Malaysia Bhd. is the largestmanufacturer of rolled aluminium products in Malaysia anda leading supplier in the Asia Pacific region with a strongglobal presence.
With over four decades of rich history, ALCOMʼsachievements are impressive, from high-profile projects forMalaysiaʼs MRT Stations, Carlsberg Brewery Malaysia andKLIA 2, to receiving prestigious Prime Minister awards inrecognition of ALCOMʼs excellent contributions.
Excelling in fin stock used in heating and cooling systems,ALCOM is a pioneer in the field, with its unparalleledmanufacturing capacity, forward-thinking technologicalprowess and cutting-edge research and developmentoperations. Itʼs no wonder why ALCOM is the leadingsupplier to some of the worldʼs most trusted brands,winning over global industry leaders including Daikin,Carrier and York.
ALCOM is the total solution-provider for all your aluminiummaterial needs. We offer highly custom-tailored services tomeet specific customer requirements, covering industriessuch as general engineering, architectural, construction andmanufacturing. With our state-of-the-art technology andmanufacturing leadership, our high-quality products areshaping the future of design in aluminium.
SOME OF OURFEATURED PROJECTS.OUR EXTENSIVE PROJECTS LIST BOASTS SOME OF THE MOSTICONIC BUILDINGS AND LANDMARKS IN SOUTH EAST ASIA.
WWW.ALCOM.COM.MY
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