How to fill gap between concrete and garage floor?

[Kvic]

I have started to clean the garage area and the concrete slab for the car driveway into the garage has the expansion material missing and grass growing so I cleaned it out and fitted new expansion material but the gap is too wide or too thin.

So I was thinking of adding sand over the gaps to fill in and hold the concrete expansion material better but I thought I should ask first.

The left side of this photo show the loose channel and then it gets tight.

The other question is painting garage doors, it is a roller door and I need to clean and paint the door. Just looks a bit faded and needs refreshing if I paint the slab? 

[EricL]

Hello @Kvic 

If parts of the gap are holding the expansion foam in place there is no need to add sand to it. The purpose of the expansion foam is to keep debris out, it also protects adjacent concrete structures and their structural steel supports. So even if some parts are loose, it's perfectly alright. 

However, if you wish to seal the top of the gap, I suggest using Gripset Betta 1L Concrete Crack Filler. The expansion filler however must be pressed down to provide a space of at least 10mm for the crack filler to settle in.

Here is a link to our best advice: How do you prepare a garage floor for painting?

Here is a handy step-by-step guide: How to apply epoxy to a garage floor by @prettyliving 

In regards to painting the garage floor, I suggest having a look at some of these discussions:

• Epoxy garage floor transformation by @maknilsin
   
• Epoxy concrete floor for large shed by @CSParnell 
   
• Painted garage floor by @Upcycler01 

If you have any other questions we can help with, please let us know.

Eric