Egg-free alternative to meriwhite/royal icing?

[KeyboardWorrier]

Ds has food allergies, and while he can tolerate baked egg, he still has to avoid anything with raw/lightly cooked egg in it. I want to make a gingerbread house this Christmas, but I'm looking for an alternative to the icings that contain egg-white to glue it together with. Am I on a hiding to nothing, or does anyone know of something that I could buy/make that will set relatively well without using egg white?

TIA

You can get egg replacer, would that work?

Doh! I didn't think about egg replacer. I haven't used it before - I try to make stuff that doesn't need eggs in the first place as I've found the recipes that try to reproduce egg-containing cakes etc inevitably end up failing/tasting nothing like the original. I have heard it gives mixed results in baking, but I suppose if you're using it just for the binding/setting qualities in icing it might not be so bad.