solver

I changed the ceiling to 84" which is code here -- your local may be different.

The Pro version has manual roofs, so you may draw roof planes yourself, or modify auto built roofs.

You can often trick the program into producing the roof you want. One way is by using invisible walls. For the extended overhang in front of the garage, you could draw a room divider just behind the garage door. This creates a room between it and the outside wall. Turn off Roof Over This Room for that space. Then adjust the roof overhang, pitch etc using the room divider. You can vary the location of that wall, and adjust the overhang to get that part of the roof to look correct.

For the back of the new garage, I was not sure how you expected it to look, so I cannot offer any suggestions.

It's best to get your walls and ceiling heights set before working on the roof, as even small changes in either can change the way the roof builds.

Once you have the plan done, and have decided on pitch and other variables, we will help get the roof as you want it. 

The trial versions are fully functional.

When you say "I can't import a picture" -- what is the problem?

Did you try raising the floor level of the deck up?

What type of siding will you have?

I would define a new wall type that is a single layer of whatever type of siding you are using, or one with additional layers as needed.

Use it to wrap the structure.

I first tried the stair back by the dining table, but it seemed to intrude into the space too much.

On the roof, the auto roof function works very well but often fails to do what you expect when there is a non standard condition such as yours. There are ways of fooling the software to get it to do what you want (generally, not you specifically) but they can be very specific to the conditions. It's best if you decide on pitch, heights etc, then tackle making the roof build.

Using Pro, I can do manual roofs, making them do exactly what I want.

What you really have is a 2nd floor, not an attic. 

I'll also encourage you to visit your local code enforcement officials with a preliminary plan. They will advise you on what they will approve, and changes they might require to your plan.

A place for the stair.

The stair intrudes into the first floor space a bit, so I covered it all across the wall instead of just where the stair is.

You may not be able to meet egress requirements for a bedroom window, so here is an idea for an alternate plan.

Closets buffer the bathroom. Big window in front is not split by the closet wall. 

Rear bedroom gets an internal window overlooking the space at the rear of the house.

Your ceiling height of 60" is probably too low as well. Here it needs to be 7' for habitable space.

Still wondering about stairs???

Consider adding a 2nd floor. Use 2 rooms, one for the loft, one for the remainder of the area -- set this one to Open Below.

I'm sure there is. If you could post some pictures or your plan file, you will get a more complete response.

There may not be a clean way to do the rear roof area on the added garage.

Here is one idea. Pitch is 8 in 12 on the garage and 2nd floor addition, 3 in 12 everywhere else.

I reduced the height of the added garage to bring down the scale a bit.

Take a look at https://hometalk.chiefarchitect.com/index.php?/topic/1610-frieze-boards

What part are you having trouble with? With Pro, you can do the roof as needed. The internal gutter will likely need to be manually detailed.

For the gable ends. Go to the 2nd floor in plan view. Notice the gable ends are shown as invisible.

Select them, and delete them. They will automatically rebuild correctly.

Is the roof in my image what you want -- including the extended overhang in front of the big garage? Auto roofs sometimes have a problem where 2 roof planes join in an unusual way.

Your local building inspector can tell you about the footings.

For some reason, changing the Floor to -12 would not stick until I changed the stem wall. The Floor kept going back to 16".

Your foundation also needs rebuilding.

If you look in a Doll House view, the wall between the garage and entry has some problems at the bottom. Guessing it's because of the stairwell.

This is how I would do it.

Stairs will cut a wall, so placing a wall just under the stair will give you a wall where the top follows the underside of the stair.

For a wall that acts as the railing, see the images.

You have some floor height issues, I think. Fixing these will go a long way in correcting the other problems.

The gable wall above the garage doors needs to have No Room Definition unchecked. That will make the space above the garage a room.

Take a look at what I've done, and post back with any questions.

HomePlan3D_M (eric).zip

Something like this?

Posting the plan file will make it much easier for us to help.

Post the plan file if you wish and I'll look at the soffits. Make sure it's not open in the software.

You can place many types of light just above the soffit, but you really need something that points up. Not sure if there is one in the library or if you can change the direction of a stock light.

You can place a soffit anywhere and shape it as needed. Place it, move it into position, then size it as needed.

If you move the lower roof out from the wall, it works as described.

I placed those in a camera view, but plan view really works better.

 Place a soffit along your gable wall. You can be on the attic level, or below. 

Open the soffit and select Sloped Soffit. Take a look in 3D -- you may need to rotate it so the angles are correct. Rotating is best done in plan view.

Open it again and select Place Under Roof. That will change the slope to match the roof. 

Change the dimensions to suit. 

In an elevation view, drag the ends into position and move it up or down as needed.

Once you have one side done, copy and reflect about the centerline of the gable to get the other side.

You should not need to calculate any values, and the outline will show where it is, and the size in plan view, but it cannot show the angles, so it may not look as you expect in a camera view.

It helps to have a plan view and a 3D view open at the same time -- split screen or 2 monitors, so you can see the changes as you make them.