So I just finished building this cute little cul-de-sac type of apartment complex (separate houses.) However when I type in the code to convert it to apartments it tells me that I have an invalid apartment. I've narrowed it down to which apartment is causing the problems but I can't see any flaws. It's not the first one I've built so I understand the rules...

- Each apartment does have only one unique separator door and it is facing the correct direction.
- No apartment has any balconies or patios so there is no issue there.
- There are no garages, so that's not the problem.
- I have not used any of the "low-fencing" inside any of the apartments (there is some outside but that should be fine.) Just for the sake of it, I did try removing some of the fencing, but that did not fix the problem.
- I have tried moving the unique separator door to no avail, no matter where I move it, it still gives the invalid apartment error.
- There are three other nearly identical apartments on the lot using the same exact style/fencing/doors/windows etc... so why this one won't work is beyond me.
- I have gone though the game faq and wiki.
- I have tried removing custom content.


Here are some pictures if it helps:

Are you using the correct apartment doors (called "Unique Separator")?
They have a door mat which should be on the outside of the apartment

yes, i sure am.

Baffling - looks ok - however, where is the mat outside the door? I cannot see it on the screenshot. Other than that, looks fine. Maybe package the lot and post it in repair and let someone have a look at it?

I have a feeling that is the hotel door from bv not apartment life, can be easily mixed up as they right beside each other in the list, swap the door and it will work

I have had several problems with the staircases. What happens if you take it out? There is something odd about that door. It looks like the hoteldoor. You need the one with the matt.

YEP that is a hotel door not an apartment door, look through the door section again and find the door icon with a mat and you can only see the bottom of the door

my unique separator door's floor mat disappears when I add floor tiles over it..I am having the same problem and nothing I do works..so IDK

That's definitely the apartment door; the hotel door's number plate is rounded at the top, instead of flat. Also, the hotel doors have a handle instead of a knob. So that's not the issue. I can't see a thing wrong with this unit. Could you possibly post screen shots of the other units as well, just in case one of them has an issue? How were you able to narrow it down?

A few notes:

1. You can have a patio/balcony, as long as the ONLY way into it is through the apartment. A patio must be fully fenced, with no gate, and a balcony cannot have stairs that go to outside the apartment. As long as they are unit-accessible-only, though, they work. 100% sure on that, as I have used them many times in fully functioning apartments that I have built.

2. You can have a garage, as well, as long as the ONLY exterior door is the actual garage door that the car drives through. That one outside, and one to the interior of the apartment, and garages work. Of course, the units all have to be close enough to the street, but it's doable. Again, sure, as I did this with some "duplex-type" buildings in the past.

The missing door mat seems to be significant, though. I always build my own apartments, and have never had this issue, so I suspect that whatever is causing this is your problem. I totally understand what an issue it can be to remove all the custom content, but you might not have to. If you don't have it, I highly recommend getting this - http://www.modthesims.info/d/227925 - Delphy's Download Organiser - and using it to help locate the culprit. What you do is install it, then open it and allow it to go through your downloads. Do this with the the game closed. Once it's done (can take a little time, but not too much), you can use that to sort things. Someplace not in the downloads folder, make a file folder to temporarily relocate possible problem files. You can then sort the stuff by floor tiles (one possible culprit), doors (another, especially if you have custom hotel doors installed), and mods. Since the door mats are not showing, it's probably one of those. Any hotel door downloads would be my first guess, followed by some mod having to do with hotels. With the Organiser, you select he file you think might be an issue (with VERY handy descriptions, so you can actually know what is what!!), and then select the option to move that particular item to another folder. Use the option to select one yourself (at the bottom), and go to the folder you created to remove things to test. After you move the most likely packages, go back into the game and see if the problem is gone. If it is, you know that one of the items you removed is the issue. If not, you can keep looking. Sorting for this purpose is very easy, as there is a little selector menu at the bottom which you can use to sort by certain sorts of files, such as the floors, doors, etc. You can even type in "door", for example, to get just those. Assuming you do resolve it that way, you can then, one at a time, add back in the possible files, reloading the game each time (yes, tedious), and thus narrow it down to the one issue.

The only other thing I can think to do is delete the door, and rebuild the wall section where it is, then re-add it, and see if the mat stays visible. Maybe somehow the lot got buggy. Do the mats vanish on all lots where you try to use them, or just this one? Know this thread is a bit old, but since there isn't a solution thus far, hoping the OP or someone else with the problem can find some help with the tips. Know how frustrating such an issue can be!

I would try making a test lot, with a simple box divided into apartments with 3 doors and see if that can be converted. The no mat thing was what I noticed straight away. If that works you can know there is something wrong with some part of your proper apartment, and if it doesn't work then it might be time for a cc pull.

Aaaand I just replied to a 4 year old thread. -_- People, I think they would have moved on from this problem...

Funny enough, I recently had this error and tried to read this thread to resolve it. I couldn't find my answer, but I just had to build a second one to isolate the issue.

It turns out that I had a custom garage door. When I changed my garage door to the Maxis garage door (custom colors were accepted, just the custom garage), everything worked just fine! (Note: If it works, you won't get the invalid pop-up. The "residential" mailbox will automatically change to an apartment mailbox when you do the cheat: changelotzoning apartmentbase. If you get the invalid error popping up, make sure you use the cheat "changelotzoning residential" before you do more edits, just to be safe.)

Issues in the past that I was able to fix included:
- Make sure your gates and walls are completely closed in. Sometimes a tile was missed and that will trigger an error. You can't have multiple external entrances to the same apartment.
- The Apartment Life low banisters are fine around the stairs but are not if you use it as railing around something like, say, a two-story window.
- You can have a garage with a regular, non-apartment door to access the apartment (i.e., the apartment door on one side, but if you want an attached garage, you can use a non-apartment door to access the garage). The Maxis duplex builds have the same with the non-apartment door to the garage. You just can't have multiple apartments accessing the same garage.
- You may get the error if you have zero fire alarms in the apartments. Funny enough, I've built apartments without bathrooms on accident, and that doesn't trigger an error.
- You can't have elevators in the apartment units themselves.


I hope this can help someone! Happy Simming!