Book about magician apprentice and stairway

Question

Around 1998 I read a book about a young man.

Something about wanting to rescue his father? The young man goes to study magic where his father lived, and studied all the things his father studied, notes, books, etc. He learns how this place/study/castle(?) uses magic to keep the weather out and the air perfect inside. He is alone.

After this time, I believe he has to go about a glass or crystal stair - to another dimension?- to fight a bad guy, possibly a dragon or other sorcerer. It's a series. This is a big deal to him as the young man must leave his life behind and/or cannot return.

I have been looking for this book for a while now with no luck.

Answer 1

This is "The Crystal Stair" by Grace Chetwin, part of the Gom series of books.

Gom has finally found his mother, and as she leads him through the ancient forest of Dunderfosse, he makes many wonderful friends, including the immortal horse Stormfleet. Then, Harga must leave to fight in the starworlds' battles, and Gom sets off to learn more about his own powers of wizardry.