Pulled a entry door to find no subfloor and notched joists
The surprises keep popping up in my recient house purchase! My front door got pulled for replacement and we discover some enterprising person decided to cut out the subfloor & notch the floor joists to fit in their door. 🧐 any particular advice on what to do here and ensure airsealing from basement/mainfloor/outside?
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Replies
Tia, this is a typical solution to a remodel problem. Modern pre-hung doors have quite a thick threshold, and cutting away the subfloor (and even a bit of joist) lowers the unit and can reduce the trip hazard. Or, it could be that the header above was too low, and it was easier to find extra vertical space in the floor. Doesn't matter; you're right about needing to airseal and patch that subfloor. Ideally, you also want to slope the new rough sill outwards and incorporate waterproofing under the new threshold. If indeed there is a vertical space crunch, then what to do about it has now become your conundrum! I wouldn't hesitate to saw away some of the header above to gain space, but this now means a bunch of extra trimwork.