Spelt flour isn’t one of the best flours for recipes requiring a high rise, like bread or cake.
Wheat flours have the advantage when it comes to rising because of their gluten content. Einkorn flour has less gluten than the average wheat flour, but it has enough to make it work for this purpose.
Barley and Kamut flour both contain some gluten, although it’s a low percentage. If you’re looking for a slight, but not substantial rise from your baking, these may suffice.
If you’re using a gluten-free flour, you may need to incorporate baking powder in order to ensure that the finished product is properly risen.