Over time, when you work in Revit you will create warnings, some of the warnings will stop your work and prompt a solution (for instance, an invalid sketch when drawing a floor) and some of these will just appear and allow you to either fix them or continue your work (for instance, duplicate room numbers). If you ignore such a warning, it will be logged in the Revit warning system and sooner or later you should look through the list of warnings and correct them. The list of warnings are available on the Manage-tab. There are many reasons why regularily going through your warnings and correcting them is a good policy in any Revit project. Some warnings are simple design problems and some more serious issues which could affect Revit's performance and stability. Correcting a warning can be quite a challenge though - and we hope that this list of common warnings and their solutions will help you out.

Common Revit Warnings
	Walls are slightly off axis and may cause inaccurances. This error occurs when walls are almost 45º, 90º or 0º to the internal coordinate system - the off-angle is usually very small, about a thousands of a degree. It can occur when if you have modelled walls from an underlaying DWG-file which is not as straight as Revit would prefer, or when you have rotated the project against such a line. It can also occur when you join to walls that were almost inline. There are a few different ways to correct the error: Redraw the wall and make sure to snap correctly - that is, do not snap an endpoint Draw a line and use the Align tool to align the wall to the line Use the Naviate Align Walls function to realign the wall or all walls in your project. This is a common warning and important to fix - an off axis wall might be difficult to dimension and an elevation towards such a wall has been known to cause instability issues in the past. Revit does not like these lines, and both performance and stability issues might occur - you can of course make walls with an angle in Revit, just not such a small angle.
	Highlighted walls are attached to, but miss, the highlighted targets. This means that you have attached walls to, for instance, a roof or a floor and then the target has moved so that the wall can't attach anymore. Walls that miss their target will of course create unpredicatble results, the wall will still have the height required to attach so if the floor is moved, the wall will become higher. To correct the error, either detach the wall or move the target object so that they attach again.
	Highlighted walls overlap. One of them may be ignored when Revit finds room boundaries. Use Cut Geometry to embed one wall within the other. This warning obviously occurs when walls are overlapping each other - a room might set it's boundaries to either one of the walls, leading to the wrong area being reported. Embedd walls is used to host one wall inside another - if that is what you tried to do, then you use the Cut command when the walls are overlapping.
	Highlighted elements are joined but do not intersect. This warning occurs if you have used the join command on two elements which are not physically next to each other. To resolve, either move them together again or disjoin. A simple way to disjoin is the disjoin command (the same button as join) or by using the move command with disjoin checked. The Show Related warnings also offers a "Unjoin Elements".
	Insert conflicts with joined Wall. This warning appears if, for instance, a window or door obviously collides with a wall. To correct, simply try to move either the wall or window/door.
	There are identical instances in the same place. This will result in double counting in schedules. This warning occurs when to elements are placed exactly on top of each other, usually the result of an accidential copy/paste operation although misbehaving groups could also cause similar warnings. To resolve, simply delete one of the elements. Note that Revit only displays this warning when the elements are exactly placed at the same place - if the elements are just one millimeter apart, the warning will not display.
	Area separation line is slightly off axis and may cause inaccuracies. Room separation line is slightly off axis and may cause inaccuracies. Line is slightly off axis and may cause inaccuracies. These are all similar to "Wall is slightly off axis" and the method of correcting the warning is also the same - except that the Naviate function does not operate on single lines. There might be lines that are following an off-axis wall, so a good idea is probably to first correct the walls and then the lines.
	Line in Sketch is slightly off axis and may cause inaccuracies. Line in Massing Sketch is slightly off axis and may cause inaccuracies. This is similar to the previous warning, but concerns a line in a sketch so you might need to first find the object containing the sketch and the correct the line. The line might, for instance, be in a floor, roof, ceiling, stair or similar object. Not resolving these warnings can cause walls and lines drawn against these to also be off-axis.
	Highlighted lines overlap. Lines may not form closed loops. The warning will occur if you for instance have two lines on top of each other, typically when you are creating an object in a familly, but can also appear if you combine an opening object with some detail lines.
	Two elements were not automatically joined because one or both is not editable. This is a temporary warning and occurs in Worksharing environments, basically Revit would like to join for instance two walls, but one of the walls is owned by another user. Once the other user synchronizes to central and/or releases the elmenents, the warning may disappear. If it does not, sometimes you will need to rejoin the elements once more by trimimg or nudging them a little. In some cases, the joined elements may not even be close to each other and still have this warning, they might have been unable to join because of worksharing troubles once and the warning remains. Try to trim them together, or recreate one of them.
	Can't make monolithic Stairs. This warning occurs if the sketch defining a stair is invalid - the stair is actually invisible in the project and removing it requires you to select it directly by ID with the Revit function "select by ID" or the Naviate Filter command.
	Can't end Stairs with Riser because Riser Thickness is too small. This is a common warning in many templates - and occurs naturally because you have a sketch based stair run with "end with riser" checked and zero written for riser thickness. It does not appear for Component stairs. The main cause is also usually monolithic stairs with "end with riser" and zero for thread thickness. There is generally not much to gain from correcting this warning, if you would like a monolithic stair run with "end with riser" and no thickness on the last riser then you will need to accept having this warning in your project. You could also redraw the stair using the component stair instead.
	Elements have duplicate 'Mark' values. Mark is a sequenced, instance, number which is updated automatically on doors and windows when these are created - in a worksharing environment it can happen that two users create elements with the same Mark number. To resolve this warning you will need to look over your Mark numbers, perhaps in a schedule. A faster way is to renumber your objects using the Naviate Door/Windows tools command. The wrong value on Mark could lead to incorrect scheduling, tags and annotations.
	Elements have duplicate 'Type Mark' values. Similar to the previous warning, but a type level parameter - this might be updated incorrectly when creating new types or entered incorrectly by a user. The wrong value on Type Mark could lead to incorrect scheduling, tags and annotations.
	Elements have duplicate 'Number' values. The same kind of error as Mark, but applies to rooms, spaces and areas. The wrong value on Number could lead to incorrect scheduling, tags and annotations.
	A wall and a room separation line overlap. One of them may be ignored when Revit finds room boundaries. Shorten or delete the room separation line to remove the overlap. This warning occurs when a room separation line overlaps part of a wall - this can lead to quite strange room area calculations and should be resolved. To resolve, you will need to find all overlapping lines and either shorten or delete them. Please note that sometimes you may have overlapping separation lines and the wrong areas (as pictured) but recieve no warning. If you see any room separation warnings consider taking the time to investigate all your room separation lines.
	Area is not in a properly enclosed region Room is not in a properly enclosed region This warning occurs when a room is not enclosed by walls/separation lines, or an area is not enclosed by boundary lines. An other reason could be a not room bounding link or an opening object which lets the room "slip out" from it's area. To resolve, simply verify that the rooms and areas are enclosed - if the room is supposed to be enclosed by walls from a linked file, verify that the link has "Room Bounding" checked. There is also a setting on each level, Computation Height, which can modify how high the room is to search for bounding elements. This is a very important warning to correct, since your schedules and tags will not be correct.
	An elevation symbol references views on more than one sheet. It will show a blank sheet reference. To show the correct references, use a separate elevation symbol for the views on each sheet. This warning occurs when you created elevation views and used one symbol to create all four elevations (checked the boxes on the elevation symbol) and then put them on different sheets. Revit will not know what Sheet Number to show on the elevation symbol and create a warning. To resolve, simply gather all elevation views on one sheet, or use more elevation symbols.
	The Actual Tread Depth of stair is less than the Minimum Tread Depth specified in the stair type. The Actual Riser Height of stair is greater than the Maximum Riser Height specified in the stair type. Each stair type has a minimum tread depth and maximum riser height - if you set the tread depth to narrow or choose to have too few risers (steps) in your stair this warning might occur. To resolve the warning, either change the minumum and maximum settings on the type properties and/or create a new type of stair which allows your settings.
	Rectangular opening doesn't cut its host. Opening not cutting anything. This warning occurs when you have a opening object which has been moved to far from the object it's cutting. To resolve you will simply need to move the invisible opening object back so that it cuts the host, or optionally, delete the opening. Not resolving this error will leave opening elements floating around your project and perhaps creating incorrect scheduling.
	Conditions for wall embedding are no longer satisfied. This warning occurs if you have embedded walls into other walls by using the cut command and then moved the embedded wall too far away from the hosting wall. To resolve the warning, if you are able to select the element you can try Show Related warnings and select release embedded wall. However, in some cases this will not work and then you can try cut and paste same place instead.