SPC Flooring
Strength:-
i. Water resistant
i. Compared to laminate flooring - Water resistant
ii. Compared to luxury vinyl plank (e.g. Allure Flooring) - Allure flooring is better in terms of water as vinyl is water proof

ii. Dent resistant compared to wood as SPC = stone plastic composite
iii. Thermite-proof (stone and plastic)

Weakness:
i. Malaysia market has a lot of cheap low quality 4mm SPC with no attached underlayment. (Made from China e.g. RM4-6 per sqft)

ii. Feels quite hard compared to wood. It feels almost the same hardness as ceramic tiles.

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How do you consider one as low quality?
i. Not Virgin material (can google)
ii. SPC composition (Stone more than plastic), very stiff, if bend then pecah; higher quality ones are more flexible
iii. body thickness: 4mm is the thinnest (3.7mm i would avoid this at all cost). I would go for 5mm at least.
iv. Wear layer thickness: 0.3mm is the thinnest; i would go for 0.5mm.
v. Lack of UV layer (e.g. near window or door, color fade easily)
vi. The click and lock easy pecah if you use your finger to bend
vii. Wood pattern lacks variant, repeats a lot

As for underlay (PE foam), normally 4mm body, they wont use >1mm thickness underlay because the body is thin, any uneven surface, the click will break easily. If 5mm, possible to use 2mm thickness underlay. If you want better, can go for EVA foam.
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Brands in malaysia
i. China SPC with no brand/ Protex (I would avoid these, most likely your contractor is supplying you this to save cost)
ii. Teraflor/ Genflor (Malaysia brand i think)
iii. Shaw Contract (US Brand)
iv. Aqua SPC

I would advise you to google and visit SPC suppliers nearby your area, touch and feel the SPC samples, then make a decision.

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