Re: White edge/foundation on walls

@NastyLenny On areas like this most of the time either 'Exterior Trims' or 'Friezes' are useable, depending on which floor/level and the type of 'room/area', wall or fencing, etc. you are trying to apply a trim to, and depending on which packs you own in some cases. Please see the screenshots below for where to find these in Build Mode. 




Even 'Spandrels' will sometimes work in the right conditions.


(Plus obviously some areas are actually a roof trim, but that's not what you're looking for.)

I do find that there are conditions, such as over stairs, where some of the trims are temperamental at times. Sometimes altering the formation of an area or re-drawing a room sometimes changes this. In the case of your porch, you may want to experiment with creating a 'room' of the area on both floors (1st and 2nd) then deleting the unwanted walls/replacing fencing to see if the trim will then apply for you. Just experiment. Let me know if you have further questions on issues on this or if I misunderstood the issue. Thanks and have fun!