Hi @nila,
Wow, that rat has certainly done a number on your door.
To carry out a temporary repair, I would suggest using Turbo 500ml Builders Bog. This is a 2-part filler that sets hard as a rock and should do a great job of keeping the rats out.
Start by removing the door from the frame so you can comfortably work on it. You might need a hand with this as glass doors can be fairly heavy.
This can be done by unscrewing the hinges from the frame. Make sure to leave the hinges attached to the door for ease of reinstallation.
You might like to check out How To Remove a Door for some guidance.
Once the door is located in a suitable working position, remove any loose material that could prevent good adhesion of the Builder's Bog. It doesn't need to be too tidy, just make sure to remove the stuff that comes off easily.
After this, make a basic formwork out of cheap sheet material such as this CUSTOMwood 3 x 900 x 600mm DIY Raw MDF or even some strong cardboard you have around the house. The formwork can be held in place using some Craftright Quick Action Clamps while the bog is setting.
Mix up the Builder's Bog following the manufacturer's instructions and fill in the area inside the form. Once the Builder's Bog has set, remove the form and sand it to match the timber using a Trojan 120 Grit Angled Sanding Sponge. It can then be painted to match the rest of the door.
This will give you a good cosmetic repair that should last until you replace the door.
Let me know if you have any further questions.
Jacob
