When a laminate benchtop is burned, the damage cannot usually be repaired as the laminate has been melted and scorched.
Your best option is to replace the benchtop. Bunnings has an extensive benchtop range, as well as a custom benchtop installation service.
The most effective option other than replacing the benchtop is typically to paint it. Fortunately, we have products such as the Dulux Renovation range that are perfect for this task. Many of our members have successfully transformed the look of their laminate benchtops. Here's a helpful guide: How to paint a kitchen benchtop with Dulux.
If you want to paint the benchtop, I would start by gently trying to remove the discolouration using Scotch-Brite 155 x 100mm Heavy Duty Scourer Pads and dishwashing liquid such as Morning Fresh Lemon Dishwashing Liquid. Apply the soap to the affected area and scrub with the pad in a straight, left-to-right motion. Avoid circular scrubbing, as this can further damage the surface.
Once you see that this is no longer having any effect on the discolouration, try using Flexovit 100mm x 1m 400 Grit Wet And Dry Sandpaper in the same manner. Be careful not to rub too hard, you are simply trying to remove the discolouration, not the actual laminate coating.
Once you have removed as much of the discolouration as possible, you can fill the areas where the laminate has burnt through with PC-11 White Epoxy Paste, which can then be sanded to a suitable finish and painted.
Another option is to cut the damaged portion of the laminate with a Stanley Knife and fill the damage with UNi-PRO Multi Purpose Interior Filler. Your goal is to fill the damage to the same level as the benchtop. Once the filler cures, I suggest sanding it flat using a Rocket Sanding Sponge. Once the surface is nice and flat, then you can paint it. - EricL
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