SealPro PS GG

Additional Information

Width to Depth ratio:

Design of the joint should be done keeping in view the movement capability of the sealant. Normally a width to depth ratio of 2:1 must be maintained in joints subjected to movements. Joints should be designed so that total movement due to concrete shrinkage and thermal change does not exceed the ± 25% (MAF) movement accommodation factor related to the joint width, in accordance with the recommendations of BS 6093

Joint width design recommendations:

• Sealant depth shall never exceed joint width.
• Minimum 5mm for metals, glass & other impervious surfaces.
• Minimum 10mm for all porous surfaces.
• Minimum 12mm for non-moving construction floor joints
• Minimum 20mm for joints exposed to hydrostatic pressure or permanent immersion. N.B. Joints subject to total immersion should have a 1:1 profile.
• Minimum 20mm for expansion or movement joints exposed to traffic with the sealant tooled to a depth of 3mm below flush.

Joint depth design recommendations:

• For non-immersed expansion joints, subject to cyclic movement, and greater than 20mm wide, it is important that the depth should not exceed half the width to optimize the elastomeric properties of the joint sealant
• Minimum 6mm for non-porous surfaces
• Minimum 8mm for porous surfaces
• Minimum 20mm for trafficked joints
• When using filler boards in expansion joints to achieve the correct depth, it is essential to use a backer rod or insert a bond breaking tape into the joint in order to prevent 3-point adhesion

Application Guidelines:

It is recommended that joints to be sealed with SealPro PS are left till the final stages of construction when internal temperatures have stabilised, and initial concrete shrinkage has taken place. The bulk of concrete shrinkage will take place within the first 28 days therefore sealant works should be delayed for this minimum period.

Joint preparation

• Before applying SealPro PS, check the joint edges for soundness and if found weak, cut recess and fill up with suitable repair mortar. To ensure optimum adhesion the joint faces must be sound, clean dry and free from any loosely adherent material which could prevent adequate bond to the substrate. All traces of contaminants such as oil, greases, chemicals and laitance should be removed.
• All metal surfaces must be free of all rust, scale and protective lacquers. Use a suitable solvent to remove any traces of oil or grease.
• All dry residual dust from joint cutting operations should be completely removed using a rotary power brush, dry abrasive blasting or other approved means. Blow all joints clean using dry oil free compressed air.
• When required, use a foam backing rod to act as a bond breaker and taking care to maintain the correct width/depth profile. It is recommended to use masking tape to obtain neat straight edged seals. The tape should be removed immediately following the completion of the application.

Coverage/ Yield:

GUIDE TO SEALANT QUANTITIES

Number of litres required = Joint width (mm) x joint depth (mm) x joint length (m) /1000

     * Care should be taken to allow for wastage

Priming

• The use of a primer is always required on porous surfaces. Joint faces must be clean and dry. Wire brush thoroughly and vacuum clean concrete and masonry surfaces
• One thin coat of SealPro PSP (a single component chemically active liquid primer, recommended for all porous substrates namely concrete, stone, brickwork, timber etc) should be applied using a clean, dry brush, ensuring complete coverage.
• Avoid over priming resulting in an excess of primer in the base of the joint or application beyond faces.
• Coating should be removed and the coated surfaces should be treated as above.
• Wood surfaces must be clean and dry, cut back or abrade where necessary to sound timber.
• Priming is not normally required on non-porous surfaces when using SealPro PS in dry, sound, well prepared joints, or joints which have been reformed using a suitable RepairPro repair mortar, except where glass or glazed surfaces are to be permanently immersed in water. Thoroughly solvent clean the surfaces
• Iron and steel must be protected with an anti-corrosion primer prior to sealing. Remove corrosion or mill scale by grit shotblast, wire brush, grinder or chemical remover. Degrease the surfaces with solvent.
• The mixed SealPro PS must be applied when the primer is tack free, that is after the evaporation of the solvent but before the primer film has completely reacted. After 3 hours the surfaces must be re-primed before applying the sealant. The flash off time is minimum 30 minutes and maximum 3 hours.