Save-the_whales - It doesn't matter whether or not you understand why the foundation needs to go there, just place it there. I myself don't even know.
Regarding the placement of the windows - 'Step 10: Place your windows as show below (make sure the object placement grid is pointing outwards). Additionally, as feldynn and nedumaran have pointed out, make sure you paint your room before you place your windows. If you do not, you will have a hard time painting them after you place them; you will also get the 'unfinished room' moodlet if you fail to do so.' (See picture below step 10).

To clarify, you do not 'need' to put the foundation around the edge; however, sometimes the foundation level will magically have no floor guides, and you won't be able to place the windows easily. It can be done completely without them, but I included it so beginners can grasp the concept without any issues.

Sorry for my conveniently late reply.

Help! I'm attempting to do this tutorial and I'm having major problems with step 7. It won't allow me to create the wall. It keeps saying "attached to wall" and I don't know how to solve this. Any help? Please and Thank You!

thanks for sharing! nice tutorial

I had that same problem, I turned off the constrainfloorelevation cheat then deleted the foundation, seemed to work fine for me..

Hope this helps :p

sup new to sims 3 do i have to enter "false" at the end of constrainfloorelevation ?

Thx so much for the tutorial!! It simply a beautiful way to enhance our sim homes...

i love this tutorial. you don't know how many houses i've made with this tut!

@ King1gangsta--First of welcome. Secondly, yes you need to put false at the end to turn the restraints off. You will more than likely get an error message saying the cheat is not recognized. TS2 made it a little easier by only needing on/off at the end of cheats. Think of it this way: true for on, false for off. I have yet to use many cheats in TS3 as I am working to get my new world landscaped and such but used it several times in TS2 as can be seen in many of my lots.

You can't see the pictures. It's kinda hard to see what's going on without the pictures.

The permissions on the host server were compromised by some toothy rodent.

Is the final result pics from an actual home on this site?

Wow! that's amazing. thank you for the tutorial i think it would be better if you have a pdf of this though

this is great. very clear images! inspiration for a greenhouse. thank you!

hi,
Finally managed to make this work.
Thanks for posting!

Thanks for this excellent tutorial I used it and love the look of it in my houses. The other thing I liked about this it was so easy to follow and boy do I like easy tutorials.The last thing I need to say is keep up the good work!

Did you take all the photos for this tutorial down? All I get is Image is not available, or does not exist. It's kind of worthless without the photos.

I have re-uploaded the images.

I am also getting the "attached to wall" error and not able to place the wall "under" the wall in the cut out area. Any ideas?

I don't usually remove the 1 tile foundation inside the room on each side. It may have a purpose, I don't know. The cfe wall makes a slope one tile wide, that might be the reason why it's like that. If you can just stuff the wondows on the walls on both floors without the slope being visible, you're fine. If you get an error about attached to a wall it's like some people say above, you have to turn the cheat on and off all the time: constrainfloorelevation false - constrainfloorelevation true - constrainfloorelevation false blah, blah, blah. If you have a blank line in the cheat window, use the arrow up and if your last cheat was constrainfloorelevation false, just change false to true and press enter.

Using cfe a lot can be tedious work. If you cannot remove the 1 tile cutout, don't worry about it. Just find a way to hide the one tile sloped wall. Make a room there or put a plant in, whatever.

It shouldn't happen if you've followed the steps and are using level ground. As you can see in Step 6, you have to cut out an additional square of foundation. When you fill in the wall underneath, you can't go all the way to the edge of the foundation. You have to leave a space (See Step 7).

You will also get this error bubble if there are tiles above where you are placing walls.

Thank you so much for sharing your knowledge. This has been stumping me for over a year until I found yours, and got it on the first try! Now I can teach my kids a new skill too, they've been building more recently.