Does anyone know how many batches of royal icing I would need to glue 22 gingerbread house foundations together. The royal icing that I am providing is only to secure the foundation, not for decorating. The royal icing will secure the pieces to a milk carton.

It depends on how large each house is going to be. Is this for the kind that is built with graham crackers around the mini milk carton? If so, I would have thought two batches (total 1kg icing sugar) would do it. I used a double batch yesterday to decorate 100 3-4" cookies, so I would think that would be more than enough.

Thanks for your response. I needed the icing before I saw your response. I ended up making 3 batches of icing as I also needed icing for cookies tomorrow. They used three milk cartons glued together as their base for the graham crackers. Before I got there I had filled 12 pastry bags with royal icing. I had the kids partner up to share the icing. It worked out great.