Fillers and Gap Fillers

Pro-Spec® Flexi-Fill


PRO-SPEC FLEXI-FILL is a durable, flexible acrylic gap filler sealant for interior and exterior applications where joint movement causes rigid fillers to crack or fall out.


PRO-SPEC FLEXI-FILL may be used for sealing gaps and joints where slight movement is anticipated (less than +/- 10% of joint width).

  • Between window or door frames and the wall
  • Along skirting boards and around cornices
  • Between bench tops and tiles
  • In corners or between the wall and ceiling or anywhere shrinkage or movement has caused rigid filler to crack

Product Range

Product Code: 9300697112521

  • Size & Pack Type: 475g cartridge
  • Color: White

Technical Features

  • Excellent adhesion to brick, concrete, timber, fibre cement sheeting, wallboards, laminated plastics, ceramics, aluminium and painted surfaces
  • Water-based – It is easy to use, and cleans up with water before it has dried
  • Flexible – Capable of joint movement of +/- 10% of joint width. Ideal for use where slight joint movement occurs and where conventional fillers will crack and fall out.
  • Paintable – Can be overpainted with oil or water-based paints after the surface has firmly skinned (approximately two hours after application). Wide joints are best left for 48 hours before painting as shrinking during drying can cause the paint to crack, allowing the sealant beneath to show through.
  • Sag resistant
  • Non-staining – Will NOT stain building materials
  • Good resistance to weathering
  • Estimated Life – 20 years

Application Tips

  • Maximum gap size recommended – width 25mm, depth 12mm
  • PRO-SPEC FLEXI-FILL is not recommended where significant joint movement occurs, such as gaps between tongue and groove boards or weatherboard overlaps
  • Not suitable for sealing around bathtubs, kitchen sinks and in shower recesses. Use Selleys BATHROOM &
  • KITCHEN Sealant for these applications.
  • Not suitable for areas of continuous water immersion or in constantly damp areas
  • PRO-SPEC FLEXI-FILL should not be applied at temperatures below 5oC
  • PRO-SPEC FLEXI-FILL is not suitable in those applications where joint movement is in excess of +/- 10% of joint width. Use the appropriate Selleys Silicone Sealant for such applications.

Technical Details and Performance

Indicative information only, not to be used for setting specifications.



Tack Free Time, Minutes (at 25oC and 50% R.H.)

60 (longer at low temperatures and high humidities)

Skin Time, Minutes (at 25oC and 50% R.H.)

30 (longer at low temperatures and high humidities)

Working Time, Minutes (at 25oC and 50% R.H.)

30 (longer at low temperatures and high humidities)

Flow/Sag/Slump (Mil-S-8802E)

Less than 2mm


(Haf/Heli TE/5 at 25oC):9,000-10,500P

Non volatile content

80% to 84% w/w

As cured – after 21 days at 25oC and 50% R.H.

Durometer Hardness, Shore A, Points

Greater than 40

Ultimate Tensile Strength, MPa (ASTM D412)


Maximum Elongation, % (ASTM D412)


Peel Strength, Anodised Aluminium, kgcm-1


Joint Movement Capability

+/- 10% of joint width (where sealant depth not greater than half joint width)


15 metres of a 5mm diameter bead

Clean Up

Any excess sealant should be cleaned up with water (a damp cloth) immediately after application. Cured sealant will need to be cut away. Remaining sealant can be softened with Selleys SOLVENT ACETONE and then removed.

PRO-SPEC FLEXI-FILL will skin after approx. 30 minutes and it cures within 48 hours to a durable, flexible seal. Allow for longer skin and cure times under cold/damp conditions. Product should be protected from rain until firmly skinned.

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