Toronto Renovation All aluminum & vinyl soffit or fascia is usually mounted over a strong base like plywood-more is necessary for prefabrication. To paraphrase, if you intend to add an addition with vaulted ceilings - no matter whether you’re build up, out, or down - your cost will be better https://video.search.yahoo.com/search/video;_ylt=AwrE.3myfFpl8kce_ApXNyoA;_ylu=Y29sbwNiZjEEcG9zAzEEdnRpZAMEc2VjA3BpdnM-?p=renovation+kitchen+Ajax&fr2=piv-web&fr=yfp-t#id=34&vid=5af2872c369761a1796610d62e0846e5&action=view