What happens when you attempt to repair or seal a moist playground rubber surface.

I have always said to my clients that the one factor that can mess up your repair or rebinding effort is weather. Everything else is pretty much straight forward. So this article is really about weather related failures and how to avoid them. 

moisture in poured in place rubber surfaces

To repair most poured in surfaces it's best to have a minimum of 40 degrees continuous for 24 hours, but most importantly a dry day. If you are expecting rain within the next 5 hours, don't bother with the repair. On the other hand, the minimum temperature to rebind is 50 degrees with 60 and above being ideal.

Now that we have gotten the temperatures out of the way, let's talk about moisture. Polyurethan binders in general, be it Aliphatic or Aromatic cure using ambient heat and moisture. Too much moister is no good. Immediate rain right after a rebinding job or a repair job will ruin your day, and so will moisture trapped in the surface. That's why it is not a good idea to start rebinding a playground surface first thing in the morning when overnight moisture might have accumulated in some areas of the playground. The effect will be immediate. You will see white blotches as in the picture above where the area was moist. If you take a microscope to that area what you will see is white bubbles. That's the reaction the binding agents have to water.  When that happens often the best solution is to leave it alone. Wear and tear should remove the whiteness. I have, however, taken a plane sander to the entire area. It's a lot of work but it does remove the imperfections. 

So if you are going to take away anything from this article it is the following;

  • Make sure the playground surface area is dry before you repair or rebind.
  • Make sure pick a day without rain to do your repair.

As usual, drop me a line at hal@trassig.com or call me at: 203-659-0456 if you have questions specific to your surface. Send me pictures if you have them and I will give you my best advice on how to go about repairing it.