Tuesday, August 03, 2010

Remodels in Revit... the untold story

To my surprise, there's not a whole lot of discussion on this very important topic. Anyone who has developed a custom remodel residential project can tell you it's not as simple, clean, or intuitive as a custom new construction residential project.

The first step is pretty staight forward... build your as-built model in the existing phase. Once an as-built model is done you might want to archive a copy of the model just incase the design scope changes and you have to start all over again with a clean as-built. Now I'm sure you are all aware that as the design develops the project architect and the client are both going to want to explore varying design iterations. The model builder is going to have to do partial demolition of walls, floors, roofs, ceilings, etc. The way most Revit Beginners go about doing this is to split the wall, floor, roof, etc into two parts and demo the half they want to remove. The problem with this method starts to reveal itself after 2-3 design iterations when the as-built model, now split into many parts, degenerates into useless plans and elevations. Constantly reshaping the proposed design on the fly without time consuming cleanups also becomes less possible.

So what do you do with partial demos? You could create a new phase between Existing and New Construction called "Existing To Remain." Then copy the element to be demo'd to the clipboard... then demo the whole element in the "Existing to Remain" phase... paste the element (into the same place) back into the "Existing to Remain" phase and then reshape the existing to remain version of our element (Some users think that a demo phase is not necessary, but it has it's benefits). Now anytime the design goes through iterations all you have to do is reshape the existing to remain element while leaving the as-built model preserved and intact.

Plans require additional cleanup, but this approach reduces the frequency and types of cleanups required, particularly obvious when you move on to elevations and sections.

EDIT: Partial additions can be done the same way you would do partial demos... copy, demo, paste, reshape. If you just add on to the length of a wall you're going to end up with a proposed design that's in pieces too. This can be important later on down the line when you want to combine phases into a new asbuilt. However, getting accurate Material Takeoffs on a remodel can add a dimension to this procedure (you might want a model that's divided into accurate pieces afterall).

EDIT: This process works with or without a demo phase.  The critical point is to group and pin previous phase work before proceeding with the next phase and then copy, demo, paste, reshape in the next phase... with plan cleanup in demo and proposed plans by regions and element overrides. Most beginners only think in terms of existing and proposed. This process considers multi-phase projects.

18 comments:

Chris Wade said...

I have to say that remodels in Revit MEP do NOT work well at all. Of course, not much works well in Revit MEP, but that is another story. New construction is much easier. Revit quite often will tell you something can't be built the way it is and this is not acceptable.

Ray said...

hey!! you have a wonderful blog. thanks for sharing your life and experience here. keep it up and never give up. you can do it.

David said...

Remodeling is really harder than just starting from scratch. Yet, now that there are several technologies available on the market, it seems that it's just the budget, time and our creativity that hinders us. Though it may still sound too heavy, we got some help from laser scanning equipment, autocads and even BIM to cure some problems. Anyway, thanks for sharing!
problems. Anyway, thanks for sharing!

mcl said...

Our office has been using REVIT for all projects for the past 8 years. At least half are remodels in either commercial or residential. there are great benefits to the phasing properties as you have mentioned. As an office we are just now successfully billing our clients accordingly for the extra up front time in building the model. Good Luck to you!
Michael

n.a.l.k. said...

Hi there,
Very new beginner here - haven't even started using Revit 2011 which our small firm just purchased. Have done most of the tutorials from 2010.
My question about remodeling projects is relating to demolishing part of a wall assembly. We often have century old houses with double-wythe brick exterior walls (about 9" total width), and the interior is finished with lathe and plaster (varies, but +/- 2").
We often remove the interior lathe & plaster, and replace with a new interior 2x4 strapping wall with insulation and drywall.
Any suggestions for a method of approach would be hugely appreciated!

DIMAS.CELLULER said...

OK thank you, all very comprehensive and clear explanation, so here I am getting the spirit

boweiz said...

this is a great post,thanks

Dave said...

I have use the Revit MEP with my business and the employees and I have not had progress with it during our building remodel. Game Apps

Dave Pilgrim said...

Our school had a contract submit a remodel with the Revit MEP and we are novices, but it wasn't a good experience. I vote new construction for the next time we add on to our Seminario

akg980 said...

I am glad you covered this topic. Remodels definitely take a while to get use to.

David Duarte said...

A demo phase would likely not be necessary for many types of commercial remodels and tenant improvements but it has saved me a lot of frustration and time on more awkward remodels like in custom residential projects. My hope was that this last post would get more people talking about remodels in Revit. Thanks for all the feedback.

alsavi said...

Hi David,
I wonder if: there is any way to demolish some of the material of an element? for example (a case I face a lot in remodels) changing the walls finishing tails of wood covering, I have coped with it creating two walls but you must cut manually doors and windows openings on that additional wall. Congratulations for the blog!
Alejo

smith tanny said...

Thanks for this article. Remodel sometimes could take more brain damage than building it from scratch.

John Hall said...

I'm starting a remodel/extension on a domestic property this weekend in Revit. Been thinking about the best (ie most efficient) way to do this. So far I think I will model the existing, save that file, then save as another file and make the changes in the save as file. That way I have the original and the proposed. I can print off what I need from existing and also from proposed. I've tried bringing a specification in from Word but it's too cumbersome so will keep the spec in Word. With these three files I can print to pdf the sheets/views docs I want into one file.
Anyone got any better/easier ideas?
ps - not yet tried Phases.
John

adam kevin said...

great information & Great post, you have done some superb details this is a very fantastic website thanks

David Duarte said...

For those of you familiar with the Graded Region site tool... What is this tool really doing to an asbuilt topo surface? Copy, Demo, Paste... so that you can Reshape.

Food for thought.

David said...

N.a.l.k.

Parts is a good candidate for this if you are not reshaping the wall.

David said...

John Hall,


A lot of users resort to separate models for each phase. Grouping and pinning previous phase work before moving onto the next phase can keep previous phase work printable and all phases coordinated, should revisions to previous phase work be required