question about flour and water in recipes

Hello, I am new to this community. I have baked yeast breads on and off for years, but when I do bake, I bake very regularly. For some reason, as of late, some old and new recipes that I have tried for challah, anadama and oatmeal breads (my current oven isn't hot enough for crusty artisan breads), each time I needed about 25% more flour than the recipe called for -- is there something with possible humidity in my apt or the water hardness or difference between European and American flours? I have mostly used some US recipes, with the addition of some from the UK and continental Europe.