Drafty stair case

Q: We have a house that was built in the 20’s. The stair case going upstairs to the master bedroom (a.k.a. attic) is leaking very cold air. We’re fighting to heat the upstairs. Can you advise what would be the best sealant for the stairs?

Any other thoughts? We would like to put in a carpet runner to help keep out the cold after we do the sealant. Thank you for your time.

A: If it was possible to gain access to the back of the stair case, this would allow you to have the stair treads and stringers tightened up and seal any areas along the wall where air in coming in.