I started building Windstad manor, but realized that I was having some incompatibilities with other mods, so the house wasn't actually appearing. After uninstalling those mods, most of what I'd built showed up, aside from the front door.

http://cloud.steampowered.com/ugc/558706247595061581/41881D713AE8FE707699FEDCBEB0072C02733AE4/

I've tried reinstalling Hearthfire, as well as Verifying Integrity of Game Cache, but nothing seems to fix the door. Any ideas would be appreciated.

EDIT: And now I've just reinstalled the game, so obviously this is an issue with my save. Are there any quest stages or anything that I could alter with the console?

Just wanted to say I'm having the exact same problem, and disabling all mods and reinstalling doesn't work for me either

Well, I managed to solve this, but get ready for some trouble.

I reinstalled the entire game and DLC, after unsubscribing from and uninstalling all of my mods. Then I had to load a save before I built the door. As soon as I built it, the rest of the house popped up and now everything's fine. Re-add mods as needed.

There's likely an easier fix than this, but after spending a good 3 hours tinkering I certainly couldn't find one. It's due to incompatibilities with a select few mods, and even after removing them the problems persist. (Although they only really affected the door, in my case...)

EDIT: In hindsight, reinstalling the entire game probably wasn't necessary. The key is to deactivate all problem-mods before loading a save before building the door. While the rest of the house is invisible with the mods, the door seems to be the only real problem that can't be easily fixed, likely due to conflicts within the cell.

Normally you would save before starting the house, then go back to that if something goes wrong. Something can go wrong with no mods, even the Xbox 360 version lost walls, doors and even floors, so with mods, you should always save in case you have to change a few things to get started. Or rebuild a few times to get finished.

Is there a console command to reset the building list? So you can build the door again and then clear the list?

I solved it too! It's a little easier fix then yours too. So, you uninstall Hearthfires. Then, load up the game, just with your normal save. All of the items related to Hearthfire are gone (like clay and stone) plus any items that were in that chest near your workbench. (Be sure and get those out first). Then, just simply make a new save. Then quit, load up Hearthfires again, and load the save you just made. Hearthfire basically got reset. So you have to build your house all over again, but if you were like me and didn't have a save before you built the front door, this was amazing.

Glad you got it fixed!

I really didn't want to have to restart the DLC all over, so I didn't take that route, but it's definitely an easier fix than mine.

Which mods did you find to be the problem? My house isn't showing up at all.

Some that caused the problem were
Birds and Flocks
Distant Detail (nexusmods mod 12866) you can get an updated version I believe that works with Hearthfire.
Real Wildlife Skyrim
Thickets and Shrub Remover
Realistic Animals and Predators

Or any other mod which makes changes to the actual game world where houses are built can cause problems with house building.

Yep. You can also get a Hearthfire compatible version of Birds and Flocks.