How to fix chipboard pillar in built in wardrobe corroding?

unanic

Hi there, looking for some advice. There is an old built in wardrobe in our bedroom which I think is more than 20 years old. I noted one of the pillars has some chipboard breaking down at the base though I don’t recall any damage to it.

Can I do anything to repair it or reinforce it or should I be worried? It looks like there was moisture there but I don’t recall it.

MitchellMc

Welcome to the Bunnings Workshop community @unanic. It's splendid to have you join us and many thanks for your question on cabinetry.

From what I can see, the base of that particle board side panel, has swollen and started breaking down due to moisture exposure. Chipboard is very sensitive to water; once it gets wet, it swells, loses its strength, and begins crumbling, just like you’re seeing.

Whether you should be worried depends largely on if that side panel is a structural element of the cabinet. In most built-in wardrobes of this age, the pillar is holding up shelves or cabinets and continued deterioration could cause problems. The bigger concern is identifying where the moisture came from and whether it was a past spill, wet mopping, rising damp or a nearby bathroom and water leak. If the moisture source isn’t found and fixed, any repair you do now may fail again.

As for repairing it, because chipboard loses its internal strength once swollen, it’s not really possible to restore it fully. The best long-term solution is to cut out the damaged section cleanly, usually about 50 to 100mm above the visible damage and splice in a new section of particleboard. You’d want to glue and screw the new piece in place, seal all edges, and maybe add a small trim or skirting to protect against future moisture. If the damage is more superficial and the panel still feels solid above, you could scrape away loose bits, let it dry completely, apply timber hardener, and then rebuild the missing section with builder’s bog. This helps cosmetically but won’t fully restore strength.

Please let me know if you have any questions.

Mitchell