Renovation is a feature set to control the display of existing, new, and demolished elements in the workflow of addition and renovation projects. It began in Archicad 15. This feature means we no longer have three of each layer in addition projects.
In the Renovation workflow, there are three kinds of elements: Existing Elements, Elements to be Demolished, and New Elements. This property is the Renovation Status. With a few unimportant exceptions, all elements have a renovation status, and it cannot be blank.
Renovation Filters control whether and how elements of the three statuses are displayed. Filters are saved with Views.
The filters control whether the elements of each status are Shown, Hidden, or Overridden.
I hope showing and hiding are self-explanatory. If elements are overridden, their appearance is controlled by Renovation Override Styles. The attributes covered by the styles are: Line type; Line pen; Fill type, pen, and background pen; and material. There is no consideration for fill category, so cover and cut fills are handled the same. (Fail.) There is only one set of override styles, and they do not vary by filter. (Another fail.) For example, you can't have one filter where overridden demo elements are dashed, and another where they are dense dashed. Whatever the style of overridden demo elements, that's the style for all filters where Demo is overridden.
Because the override styles are responsible for the appearance of overridden elements, elements of different status will have the same "natural" settings. You don't change the line type or fill color of individual elements to show they are demolished.
The styles are set in the template and should be considered set-and-forget.
There are also Additional Filter Options for existing and demolition elements. Right now the only one of these we are using is to turn off markers for doors and windows.
The Renovation palette
allows the user to control the current filter, the default status (of elements when they are placed), and the status of selected elements. It also gives access to the Renovation Filter Options and renovation override styles. The palette must always be open when working on addition/renovation projects.
And, keep an eye on it, it will try to mess with you. The current filter can change by viewpoint; it can be new construction in plan and existing conditions in 3D. When this happens, stuff will "disappear". Check the palette. Once the filter is set for a given viewpoint, it seems to stay put. (Both the default filter and the default status seem to sometimes change spontaneously, especially when opening a project on a different machine.)
The status setting is not transferred by eyedropper/syringe. The default setting on the palette always controls. You can change the status of an element in the settings dialog under Tags and Categories, but the palette is obviously easier and a better habit.
Our Override Styles
New elements are never overridden, and have no override style changes. (N.B. This is our decision, not a design limitation of the new status itself.) New elements act as if the filters don't exist. The background pen is gray (#50), same as it ever was.
Existing: The fill is overridden to be Empty Fill. The fill background pen is overridden to be pen 91 (white).
Demolished: The fill and fill background are overridden like existing, and the line type is overridden to be Dense Dashed.
Again, the natural settings of existing and demolished elements are the same as new. The override style turns them white and/or dashed.
See the appendix at the end of this post for examples of the different kinds of output.
Our Renovation Filters
01 Existing Conditions
This is used for building the existing model, and publishing the existing plans and elevations.
02 Demolition Plans
All the walls have white background, and the demo elements are dashed.
03 After Demolition
Existing elements only, with the demo elements removed.
04 New Construction
This is used for most work and output. Existing walls are white, new walls are gray.
05 As Built
This shows the project when finished, as if it were all new. All the walls are gray.
06 Show All
All statuses are shown, and you can tell the statuses apart.
How to Demolish Things
Select an element and, on the renovation palette, click the demolished button. That changes its status from Existing to Demolished. Unless the current filter is Demolition Plans or Show All, the element will vanish. If you switch to Demolition Plans, the element will reappear with dashed lines.
Demolishing a wall
That's basically it. Of course, you might have to split an element first to demolish only part of it.
The big difference between the new method of demolition and the old layer-based one is in the handling of doors and windows. Doors and windows are now demolished the same way as other elements. Just select them and change their status. There is no need to split the wall and demolish the piece with the opening in it. When you demolish an opening, it is replaced by a portion of new wall. (Note: That new piece is shown using the natural settings of the existing wall. It's no longer being overridden. That's why all elements have the same natural settings.)
Further, you don't need to split an existing wall to place a new opening. Just place it normally (check the status!), and you will have a new-status opening in an existing-status wall. And in the demolition plan, the new opening location will be shown dashed.
Renovation Filters in New Projects
Unlike layers, renovation filters have only one purpose. (There's not going to be any hacking the demolition status to do something else.) If there's no renovating or demolishing, you don't need them. So in the New Home template they are not used. The filters are in there, but they are modified to show all statuses all the time, with no overrides. All the views are set to Show All. The palette can be put away.
Special Cases Where Multiple Layers Are Still Needed
Even on a New Home project there are some sneaky existing conditions, those pertaining to the site. We have separate layers for existing and new topography contours. We have layers for existing, "demo" and new trees. We have an optional layer for backing up the existing site's mesh.
I don't think these things are what renovation filters are for, and I can't see "using" them throughout a New Home project just to address these tiny parts of the project work. So we ignore the filters, and we have a few oddball E and D layers left. To remove a tree, change its layer and enjoy the nostalgic moment.
Don't Demolish Notes, Silly Rabbit
Another layer we didn't delete is +D Demo Note. I have heard of people trying to use one note layer and then make some notes demolition notes by changing their status. This is a category error. Renovation status is for project elements, which represent real things in the world. You're demolishing that note, are you? How? What is the result of demolishing it? Keeping different types of annotation straight is a proper use of layers.
And if we still have the Demo Note layer, we still have the Demo Plan layer combination.
Changes to the Templates
Removed lots of layers.
Implemented renovation filters and override styles.
Applied filters to views.
Updated favorites and default layers.
Created pen set for existing plans.
Secondary Info on Renovation
All element types have a renovation status except hotspots, drawings, figures, and viewpoint-creating tools (Section, etc.).
Elements have a setting in the Tags and Categories division where they can be set to show only on a specific filter, rather than "All Relevant Filters". There's also a button on the renovation palette for this setting. I can't imagine an occasion to use this. That setting is where the warning comes from when you delete a filter: "By deleting a renovation filter, you will lose all elements which are shown only on that specific filter." Since we don't use that setting, we aren't scared of this warning. Further, I don't see the need to delete filters very often.
The filter settings can be imported and exported; they are xml files like Model View Option combinations. (But they import badly, extant filters can't be overwritten.)
There seem to be no GDL globals for renovation status, which seems like a missed opportunity.