I have been colouring my hair with permanent dye for about 15 years to cover the grey but now find it is very "fluffy" for want of a better word. If I let it dry naturally it is awful and then put in velcro rollers. If I blow dry it is ok but still fluffy and I feel I have damaged it over the years as every 4 weeks I do the roots and then comb through the rest of the length (just below chin length bob). I am wary of using flat irons as it may cause too much damage but do occasionally.
I am wondering if I used semi permanent if it would be less damaging. I also seem to have problems with the root area looking lighter than the rest of the length.