How to repair cracked concrete laundry tub?

[pepsp]

The project: to repair an old concrete laundry tub

Recently the old concrete tub in our laundry has started dripping from the pipes underneath. Upon commencing repairs I noticed that as well as a leak from the old metal pipe work there are some cracks in the concrete itself which look like they may have previously been repaired. Now step 1 - reseal the leaking pipes - is finished, I'm looking for some advice on how to seal the tub and repair the cracks. I was thinking of some concrete epoxy or similar but wasn't sure which product would be best to repair the cracks. 

 Ye Olde Sink

 Repaired pipework (had to use WD40 & hammer to lubricate and stilsons and a 600mm length of gal pipe for leverage to undo - incredible how strong the old putty is)

 

 

 

[MitchellMc]

Hi @pepsp,

Can you see the crack on the inside of the tubs? If not, these cracks might not have penetrated through, and only the water that weeps through the concrete is dripping out ever so slowly. There might not be any need to seal the tubs. However, it's likely not a bad idea to do, and you could improve their finish. 

You could potentially use something like Sika 1L High Strength Epoxy Repair Adhesive Concrete Fix Kit to coat the tubs, and it would certainly be good for filling the cracks. I'm a little unsure of how smoothly you are going to be able to get the coating, though. There are not many other products I can think of that would be marketed for such a job. If you repaired the cracks and missing pieces, I'd imagine you'd likely be able to paint the tubs with Rust-Oleum Tile Transformations Coating System. However, I don't believe the manufacturer has done testing over concrete, but it does adhere to grout, so I suspect it would work fine on cement.

Please let me know if you have any questions.

Mitchell

[pepsp]

Thanks @MitchellMc for the info. I can't see a crack on the inside. It would be ideal if I didn't have to seal the inside as I am worried about the finish as you suggest.

I was thinking I should seal the cracks and sand back the peeling paint on the outside and repaint it. Sadly some of the metal lining on the rim has come off, but I still think it should come up nicely.

[MitchellMc]

Repairing the outside and painting is certainly an option @pepsp. It's a bit hard to tell from the images, but is there a metal liner inside the tubs, or is it cement too? Some parts look like metal, but also it looks like chipped cement in the bottom.

Mitchell

[pepsp]

@MitchellMc The inside is concrete, and there is a metal liner around the top lip. The concrete is quite worn and chipped inside from what I imagine is many years of hard use. The metal lining on the left hand top is also completely missing in some sections 

[EricL]

Hello @pepsp 

Just to add to the suggestions made, I recommend using CPC 220ml Shower Plug Sealant or Rust-Oleum 240ml Crystal Clear LeakSeal Flexible Rubber Coating Sealer. However, I suggest giving the concrete surface a thorough clean before applying the sealer.

If you wish to repair part of the concrete surface near the waste, I suggest using Earl's 500g Concremate Expanding Cement.

If you need further assistance, please let us know.

Eric