Austria
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Understanding the Concept of SH3D - Roofs and Sloped Walls
I am a new user of SH3D and am trying to visualize a house drawn in LibreCAD in SH3D. I am running into various problems that are related to the concepts of SH3D."Normally," I have inner and outer dimensions for walls, which is especially relevant for sloped walls. The concept of considering walls by their centerline is causing me great difficulties in realizing correct dimensions for inner or outer walls. In CAD programs, one corner point connects directly to the next, so the dimensions remain precisely preserved. With the snap points in SH3D, the midpoints apparently connect, which changes the dimensions, and with sloped walls, it turns into a trial-and-error game. Realizing a sloped roof is also not clear to me. I have a house that slopes from north to south (north side 5.20m, south side 4m). Since there are no sloped wall endings, it was not possible for me to create a sloped roof, because the ceilings protrude in all directions—the walls on the south and north sides have straight endings and overlap with the peaks of the sloped south and west sides. How can these things be solved in SH3D? Best regards
Netherlands
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Re: Understanding the Concept of SH3D - Roofs and Sloped Walls
First of all: Sweet Home 3D is NOT CAD software. It was initially created as interior design software but has grown over the years to software with much more capabilities, but still it's not CAD software. In other words: don't expect CAD concepts to apply in Sweet Home 3D.
Then walls. Walls are a special type of object in Sweet Home 3D with special properties to create and join them and to allow cutting holes with objects like doors and windows. The fact that walls are measured using the center line is discussed a thousand times here and appears to resurface every two weeks or so . In short: that's how they work in Sweet Home 3D and it won't change.
Wall thickness is measured from the center line to the wall sides: a vertical wall 10cm thick and a X position 0 will have its left side at X -5 and its right side at x 5: a thickness of 10. When you join walls in 90° angle the connection point will be where the two center lines of the walls connect: in the center of the connection. You will have to get used to this concept because it differs from how CAD software handles it.
Sloped walls are created by setting different heights for the start and end points. Sweet home 3D works with levels. If you want a sloped wall on top of regular walls you do that on a new elevated level. You should read my manual "Levels explained" to understand the concept of levels in relation to walls and floors.
To create a perfect roof use the Roof Generator plugin. Read the Thread of the Roof Generator plugin because it has many tips&tricks to create the perfect roof. It's currently at 33 pages of posts but it's worth the read if you intend to create more roofs. When you download the plugin make sure you have the latest version.
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Croatia
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Re: Understanding the Concept of SH3D - Roofs and Sloped Walls
Keet is right. After a little adjustment when using SH3D, you soon realize its advantages over CAD programs. It has almost everything that CAD programs have, but is much easier to use. Depending on the project, sometimes everything is done in SH3D, and the finished project can also be used in some other 3D or rendering software.
Austria
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Re: Understanding the Concept of SH3D - Roofs and Sloped Walls
First: Thank You for the Tutorials and Links ...
I have now tried to understand and implement the levels tutorial, but I'm not getting any further. I have a floor plan (house) with 6 rooms.From south to north, there are: A living room measuring 8m (west-east) x 5.1m (north-south), wall thickness 25cm. This room is not uniform in height. The entire house section above this living room has a sloped roof (north 5.20m, south 4m). The western part has an intermediate level (room) over an area of 3m (east to west) starting at 2.20m height with a floor thickness of 10cm, extending up to the roof. This room is bounded on the west by a 10cm thick wall, which, however, does not extend into the space below. The space below is even only 2.20m high. The eastern part (the remaining 5m) retains its full house height. North of these rooms, there is a bathroom on the west with an access corridor of 4m height, and to the east next to it, a storage room with 2.40m height. Further north, there is another room spanning the full width with 2.40m height.
All my attempts always result in the ceiling height that I assign to Level 0. Every room that I select and create a "New level at the same level" for has, no matter what height I assign to it, the ceiling always at the height of Level 0.
So I don't really understand the concept...
Apparently, all rooms drawn in the floor plan (start level) remain on Level 0. How to move the rooms to their respective levels doesn't become clear to me. How to then add a common but uneven roof to the whole thing, I'll deal with later....
Netherlands
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Re: Understanding the Concept of SH3D - Roofs and Sloped Walls
When you use "Add level" it will add a level above the selected level and it will use New wall height and New floor thickness as set in the preferences. Example: in your preferences New wall height is set to 240 and New floor thickness to 20 (assuming the unit is set to centimeters). You current level is the initial level: wall height is 240 cm. Right click in the 2D view and select "Add level". A level will be added with elevation 260, wall height 240 and floor thickness 20. Notice the elevation: this level starts at elevation 260, i.e. a second floor above your initial floor. The Levels explained manual explains why the second floor starts at 260 and not at 240: it adds the floor thickness. If you already have more than one level you can right click on the level tab to add a level.
Obviously a level added with "Add level at same elevation will start at the same elevation and will use wall height and floor thickness from the preferences.
You can set the level numbers manually: double click the tab for the level and you get a dialog where you can change the numbers for that level. That is the place where you change the level height, which is the ceiling height and the height of walls on that level. The height of the ceiling is determined by the level height, not the wall height. When you add a new wall it will use the preference setting for New wall height. If you manually changed the level height you must change the wall height accordingly.
Remember that Add level uses the settings in the preferences. So if you changed a level height and add a level that new level will start at the correct elevation using the elevation of your current level but will get the height and floor thickness from the preferences. With a house with all kinds of different levels you have to manually set the numbers for each level. The Levels explained manual will help with understanding what numbers to set.
You can use as many levels as you like, even levels that mix like with a split-level home. You can name each level when you double click the tab for that level. If you use a lot of levels there is a recent plugin: Level tags manager that might be helpful but for less than 10 levels it is probably overkill.
Dealing with roofgen .... Is there a way to see the roof from inside while virtually walking into the room ?
Disable the display of the ceiling on the room and you will see the underside of the roof instead of the default ceiling. (That is the room inside your walls, not necessarily the room used for generating the roof.)
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[Edit 1 times,
last edit by Keet at Oct 17, 2025, 11:33:02 PM]
. In short: that's how they work in Sweet Home 3D and it won't change.
