Hanes Men Pant thermal underwear bottoms

My husband is always cold, even in spring and fall. He walks around wrapped in afghans or blankets and sits huddled under covers to watch TV. I saw these thermal pants and wondered if he would wear them under sweatpants or jeans. I bought a Medium since he is short and thin but has a slight tummy. He put one pair on immediately, and they are now his go-to casual warm pants around the house with no other pair of pants over them. It's just the two of us, so wearing underwear for comfort is no big deal. I'm glad I bought two pants since he's had them on almost every day since they arrived!