I have built an extension on to my kitchen. My house is a two story. When I open the existing kitchen wall to the new section there will be a 10ft opening that needs to be supported. How many 2x8 would I need to laminate to support this span.
Is your kitchen on the first floor? If so, you aren't going to be able to laminate enough 2x's together to span 10 feet. Four 2x12's together can only span a maximum of 8'4" if the house is two stories and the room width (perpendicular to the wall) is less than 20 feet. Sounds like you will need an engineered beam for your ten foot span.