How do I dispose of old paint? How long can I keep cans of paint for?

[Kim]

We are getting organised to do a bit of painting in the house over the Christmas break, to freshen up the house interior.

Our house is about 9 years old and a few of our feature walls seem to have dulled a little, so we really want to brighten them up.

That also means the original cans of paint have been sitting in the garage for 9 years, and some have spoiled.

I'd like to do the right thing and dispose of these properly - any suggestions on the best approach?  Also for the paint that appears to still be okay is there a rule of thumb for how long paint can be kept and still be used to good effect?

[MartyH]

Contact your council. They should have a paint disposal service at the waste management facility. At my council it's free disposal for residents for up to 100 litres. Apparently they partner with Paintback, which collects and treats waste paint to divert architectural and decorative waste paint from landfill. The Paintback webite also has links to places you can drop off paint. 

[AHoy]

I find it a little annoying that the paint manufacturers price smaller cans prohibitively, so you often end up buying more than you need. It's often not worth buying less than 4 litres. 

[darylhewston · Accepted solution]

@Kim

Best way I know is to just take the lid off the can and leave it in the sun until it hardens.  You can then safely throw it in the bin.  Other ideas I have heard in the past is to use kitty litter and sawdust.
With regard to how long it will last depends on how well the lid is sealed.  Most manufacturers only recommend storing for up to 2 years.  I repainted one wall at my mums place last year and then found out the paint in question was close to 10 years old.  Apparently nothing wrong with it.  I might add it did seem to take longer to stir the mix even again.

[Kermit]

We got a professional painter in a few years ago to do a few things around the house that we didn't have the time or energy to do. I was alarmed when he mentioned that the way he gets rid of unwanted paint was to dig a big hole in his backyard... 

[Emily]

Daryl's method will definitely work, but if you have a PaintBack or council site near you then I'd personally go for that, just from a sustainability perspective - the packaging will be recycled and they'll also reclaim water from the paint, separate liquid/solid waste, etc. Pretty neat process all up.
Also while I'm on this tangent, Planet Ark has by far the most comprehensive directory for recycling - pop in your location and what you've got to get rid of and it'll give you a list, tell you what's free/what's not, etc. Click here! http://recyclingnearyou.com.au/