MATERIALS:
The main materials involved in structural glazing are
Glass
Aluminium extrusions
Self Adhesive Tapes
Structural Sealant
Weather Sealant
Fasteners and Fixtures
GLASS
For glazing, usually reflective glass will be used. The quality will depend on their Relative Heat Gain values. For safety purposes, the glass can be laminated so that it becomes shatter proof.
ALUMINIUM EXTRUSIONS
Standard aluminium extrusions will be used for the purpose. The main members are
Mullion – Vertical member
Transom – Horizontal member
Sub frame – for glass bonding
SELF ADHESIVE TAPES
Usually tape of 6 x 6.5 and 10 x 9.5 will be used for normal glazing. The sizes will be decided by the design width of sealant. Currently ‘Norton’ brand is being used.
STRUCTURAL SEALANT
This is most important part of the glazing which bonds the glass with the sub frame without any mechanical fixtures. Dow corning or GE can be used.
WEATHER SEALANT
This can be used to seal the gaps in glazing which will give a weather proof system.
FASTENERS AND FIXTURES
Usually anchor bolt, screws of various sizes, aluminium clips, GI brackets, etc. will be used. In addition to this to break the contact of glass with the metal, rubber gaskets will be used in various sizes and shapes.
PROCESS
Depending on architects requirement and site conditions, shop drawings will be prepared prior to the start of the activity at site. Height of the glass will depend on the vision panel requirement which will be decided to keep the wastage of glass to a minimum.
Once glass size is decided, the same will be given to glass processor and aluminium production will be done at factory.
STEPS IN PRODUCTION
The extrusions will be protected from scratches and damages by using protection tape as a 1st step.
Transoms, mullions will be cut according to the sizes frozen.
Sub frames will be assembled as per glass sizes and will be dispatched to site along with transom and mullions.
The openable panels also will be cut, assembled and sent to site.
WORK AT SITE
Checklist of before starting activity
MAIN QUALITY TESTS
1. Peel off test to be conducted randomly on bonding to test uniformity of bonding.
2. The whole unit is to be truly vertical, and reasonably good line in horizontal direction to be established.
3. All glasses and aluminium sections to be free from chipping and scratches.
4. Weather silicon finish should be smooth and bubble less.
HANDLING AND STORAGE
GLASS
The glass should be unloaded very carefully either as the crate using a crane or one by one by opening the crate carefully. The glass storage before bonding is a very important activity. ‘A’ frames can be used for the purpose of storage with angle of 15 degree from vertical on both sides. Steel frames cladded with wood or thick rubber pad or cork sheet can also be used. Glass should be placed equally on both sides of the ‘A’ racks.
After bonding the bonded glass will be kept on floor for 2 days with wooden battens and will be kept for another 5 days for curing.
For handling of the glass, usually vacuum catchers will be used. Catchers should be of high quality to avoid slipping. Small glass can be handled on edges by hands using proper cotton gloves. For the purpose of cutting or processing the glass, wooden table of appropriate size and height has to be used with good carpet to avoid scratches.
ALUMINIUM
Usually anodized or powder coated aluminium will be used for structural glazing. Both finishes are very sensitive and are to be protected by adhesive tape before taking for production. After production at factory, utmost care is to be taken during transportation and storage at site. Sufficient packing materials and wooden battens and thin plywood should be used. At site the aluminium can be stacked length wise, in layers using wooden battens.
STRUCTURAL GLAZING
Both glass and aluminium are having shelf life less than a year. Storing of these materials in bulk is not advisable. Both are to be stored in neat dust free, damp free cool atmosphere.
ALUMINIUM COMPOSITE PANEL WORKS (ACP)
This is also a major activity like glazing. The work can be classified into two categories.
ACP STRUCTURAL BONDING METHOD
In this method ACP will be cut to size and bonded to the sub frame like glass bonding in structural glazing. All other fixing methods are similar to structural glazing, which has been mentioned above.
ROUT AND RETURN METHOD
In rout and return method instead of mullions and transoms, aluminium angles and channels will be used vertically and will be fixed to the wall first with the help of angle cleats and anchors.
ACP will be cut to size and routing will be done keeping 25mm border all around. Corners will be cutout and the panel is made as a tray by folding edges all around. Cleats of sufficient size (usually 20 x 20 x 2 thk) will be fixed on two long edges at 600 - 800 mm interval with the help of pop rivet. The above prepared panels will be fixed to the main angle frame which is already fixed to the wall vertically. A uniform groove of 10mm can be achieved by using 10 mm packing.
Proper alignment should be done for proper level, line and plump. After inspection 12mm thk streroform backer rods will be placed in vertical and horizontal groves by pushing with fingers. Backer rods will be pushed with thumb to achieve a space of 5 to 6 mm deep.
SILICONE WORKS
After placing the backer rods, weather silicone of approved colour will be applied uniformly in vertical grooves and tooling will be done with steel scrapper to achieve a smooth uniform finish. Mild soap water can be used to clean tools and hands also for touch up on rough areas after a day’s gap. Same procedure can be adopted for horizontal lines. Proper care is to be taken on junctions.
After 3-4 days of curing, the protection tape from ACP can be removed and a smooth cleaning can be done with water and rubber wiper.
MACHINE AND TOOLS FOR GLAZING
1. Cutting machine with minimum 300 Dia blade.
2. Copy router for hole, cut outs etc.
3. Drilling machine for screw holes.
4. Hammer drilling machine for anchors.
5. Screw driver and spanners.
6. Silicone Gun for bonding.
7. Small silicone gun for weather silicon.
8. Scrapper for tooling.
9. Plumb bob, sprit level and right angles for checking.
MACHINE AND TOOLS FOR ACP
1. Vertical panel saw for cutting and routing
2. Rivet for cleat fixing
3. Drilling machine
4. Hammer drill for Anchoring
5. Screw driver, spanner
6. Sprit level, plumb and right angles
QUALITY CHECK ON ACP
MATERIAL
Coating of ACP is the main criteria for quality. Knyar coating with knyar 500 resins of reputed manufacturers like PPLG is preferred. Uniformity of colour in various batches is to be tested. Flatness of ACP is the 2nd criteria. A true flat surface is the requirement after forming the tray.
PROCESS
A precision level of ± .5mm is required in ACP panel production process. All corners to be formed properly. All rough corners to be filed for smooth handling. Returns of the panel should be in right angle for straight job.
Fixing of ACP at site also demands ± 1mm accuracy. Upto 1 mm tolerance can be absorbed in silicon work. The surface of ACP work is to be in true line and level. All groves are to be uniform. The finish of weather silicon is to be smooth and free from bubbles. Proper care is to be taken to avoid scratches which cannot be repaired at all.
The main materials involved in structural glazing are
Glass
Aluminium extrusions
Self Adhesive Tapes
Structural Sealant
Weather Sealant
Fasteners and Fixtures
GLASS
For glazing, usually reflective glass will be used. The quality will depend on their Relative Heat Gain values. For safety purposes, the glass can be laminated so that it becomes shatter proof.
ALUMINIUM EXTRUSIONS
Standard aluminium extrusions will be used for the purpose. The main members are
Mullion – Vertical member
Transom – Horizontal member
Sub frame – for glass bonding
SELF ADHESIVE TAPES
Usually tape of 6 x 6.5 and 10 x 9.5 will be used for normal glazing. The sizes will be decided by the design width of sealant. Currently ‘Norton’ brand is being used.
STRUCTURAL SEALANT
This is most important part of the glazing which bonds the glass with the sub frame without any mechanical fixtures. Dow corning or GE can be used.
WEATHER SEALANT
This can be used to seal the gaps in glazing which will give a weather proof system.
FASTENERS AND FIXTURES
Usually anchor bolt, screws of various sizes, aluminium clips, GI brackets, etc. will be used. In addition to this to break the contact of glass with the metal, rubber gaskets will be used in various sizes and shapes.
PROCESS
Depending on architects requirement and site conditions, shop drawings will be prepared prior to the start of the activity at site. Height of the glass will depend on the vision panel requirement which will be decided to keep the wastage of glass to a minimum.
Once glass size is decided, the same will be given to glass processor and aluminium production will be done at factory.
STEPS IN PRODUCTION
The extrusions will be protected from scratches and damages by using protection tape as a 1st step.
Transoms, mullions will be cut according to the sizes frozen.
Sub frames will be assembled as per glass sizes and will be dispatched to site along with transom and mullions.
The openable panels also will be cut, assembled and sent to site.
WORK AT SITE
Checklist of before starting activity
- All the extrusions where glazing is proposed should be neatly plastered and black painted.
- Mullions and transoms are to be placed according to drawing and fixed to the wall with the help of GI / MS brackets and anchors and protected using protection tape.
- Proper alignment for verticality and horizontality to be maintained.
- Immediately after alignment, one more protection tape is to be wrapped on sections and granite at sill levels to be fixed.
- After drying, touch up is to be done on black painting wherever the paint has peeled off.
- At this point the second layer of protection can be removed and glass fixing can be started.
- Once fixing is completed, proper alignment is to be done once again for uniform groves in both ways.
- Then weather silicone is to be applied to seal the groves.
- After finishing all the above from inside, weather silicone can be applied to seal small gaps between granite and transom at sill level.
- Then the protection tape can be removed from inside.
- Before removing the scaffolding from out side the neat cleaning of the glass to be carried out.
MAIN QUALITY TESTS
1. Peel off test to be conducted randomly on bonding to test uniformity of bonding.
2. The whole unit is to be truly vertical, and reasonably good line in horizontal direction to be established.
3. All glasses and aluminium sections to be free from chipping and scratches.
4. Weather silicon finish should be smooth and bubble less.
HANDLING AND STORAGE
GLASS
The glass should be unloaded very carefully either as the crate using a crane or one by one by opening the crate carefully. The glass storage before bonding is a very important activity. ‘A’ frames can be used for the purpose of storage with angle of 15 degree from vertical on both sides. Steel frames cladded with wood or thick rubber pad or cork sheet can also be used. Glass should be placed equally on both sides of the ‘A’ racks.
After bonding the bonded glass will be kept on floor for 2 days with wooden battens and will be kept for another 5 days for curing.
For handling of the glass, usually vacuum catchers will be used. Catchers should be of high quality to avoid slipping. Small glass can be handled on edges by hands using proper cotton gloves. For the purpose of cutting or processing the glass, wooden table of appropriate size and height has to be used with good carpet to avoid scratches.
ALUMINIUM
Usually anodized or powder coated aluminium will be used for structural glazing. Both finishes are very sensitive and are to be protected by adhesive tape before taking for production. After production at factory, utmost care is to be taken during transportation and storage at site. Sufficient packing materials and wooden battens and thin plywood should be used. At site the aluminium can be stacked length wise, in layers using wooden battens.
STRUCTURAL GLAZING
Both glass and aluminium are having shelf life less than a year. Storing of these materials in bulk is not advisable. Both are to be stored in neat dust free, damp free cool atmosphere.
ALUMINIUM COMPOSITE PANEL WORKS (ACP)
This is also a major activity like glazing. The work can be classified into two categories.
ACP STRUCTURAL BONDING METHOD
In this method ACP will be cut to size and bonded to the sub frame like glass bonding in structural glazing. All other fixing methods are similar to structural glazing, which has been mentioned above.
ROUT AND RETURN METHOD
In rout and return method instead of mullions and transoms, aluminium angles and channels will be used vertically and will be fixed to the wall first with the help of angle cleats and anchors.
ACP will be cut to size and routing will be done keeping 25mm border all around. Corners will be cutout and the panel is made as a tray by folding edges all around. Cleats of sufficient size (usually 20 x 20 x 2 thk) will be fixed on two long edges at 600 - 800 mm interval with the help of pop rivet. The above prepared panels will be fixed to the main angle frame which is already fixed to the wall vertically. A uniform groove of 10mm can be achieved by using 10 mm packing.
Proper alignment should be done for proper level, line and plump. After inspection 12mm thk streroform backer rods will be placed in vertical and horizontal groves by pushing with fingers. Backer rods will be pushed with thumb to achieve a space of 5 to 6 mm deep.
SILICONE WORKS
After placing the backer rods, weather silicone of approved colour will be applied uniformly in vertical grooves and tooling will be done with steel scrapper to achieve a smooth uniform finish. Mild soap water can be used to clean tools and hands also for touch up on rough areas after a day’s gap. Same procedure can be adopted for horizontal lines. Proper care is to be taken on junctions.
After 3-4 days of curing, the protection tape from ACP can be removed and a smooth cleaning can be done with water and rubber wiper.
MACHINE AND TOOLS FOR GLAZING
1. Cutting machine with minimum 300 Dia blade.
2. Copy router for hole, cut outs etc.
3. Drilling machine for screw holes.
4. Hammer drilling machine for anchors.
5. Screw driver and spanners.
6. Silicone Gun for bonding.
7. Small silicone gun for weather silicon.
8. Scrapper for tooling.
9. Plumb bob, sprit level and right angles for checking.
MACHINE AND TOOLS FOR ACP
1. Vertical panel saw for cutting and routing
2. Rivet for cleat fixing
3. Drilling machine
4. Hammer drill for Anchoring
5. Screw driver, spanner
6. Sprit level, plumb and right angles
QUALITY CHECK ON ACP
MATERIAL
Coating of ACP is the main criteria for quality. Knyar coating with knyar 500 resins of reputed manufacturers like PPLG is preferred. Uniformity of colour in various batches is to be tested. Flatness of ACP is the 2nd criteria. A true flat surface is the requirement after forming the tray.
PROCESS
A precision level of ± .5mm is required in ACP panel production process. All corners to be formed properly. All rough corners to be filed for smooth handling. Returns of the panel should be in right angle for straight job.
Fixing of ACP at site also demands ± 1mm accuracy. Upto 1 mm tolerance can be absorbed in silicon work. The surface of ACP work is to be in true line and level. All groves are to be uniform. The finish of weather silicon is to be smooth and free from bubbles. Proper care is to be taken to avoid scratches which cannot be repaired at all.
