Cavity wall

[Mark Vorstenbosch]

Hi Reviteers

Why do I need to put my walls outside the core boudary to make the walls wrap?
The walls & the air barrier should be the core of the wall but when I do that the walls don't wrap.
Maybe I'm missing something can any one help understand this please.

Thanks

[rubidge]

I had a similar question in October last year ( called: Beginner's Query - Wall core )

I spoke to Darryn at your Cape Town Branch, and Shaun, and both had an answer which did not quite satisfy.

I still have a problem with this, and it is one part of the reason we have not yet bought Revit. I have only dabbled with the program to date (tutorials and a sample project), so I may have this wrong....

The problem becomes even worse if one has an additional finish layer on top of a cavity wall. We often clad such a wall.

One problem is that one must be able to dimension to the outside of the brickwork and not the finishes. The whole cavity wall MUST be the core, but then you have the problem with wrapping.

I do not like the idea of having to do a "workaround" with the most common wall type we use. It makes me wonder what other issues I would find if I did take up Revit.

Regards,

Lloyd Rubidge

[Mark Vorstenbosch]

Hi Loyd

This might not be the best thing in Revit but all the rest of the amazing things Revit can do makes up for this small problem.I can promise you that Revit is the best software I have ever worked with and Revit 8.1 is the way to go.

[iru69]

Why do I need to put my walls outside the core boudary to make the walls wrap?
The walls & the air barrier should be the core of the wall but when I do that the walls don't wrap.
I don't understand the question. Can you post an example file (or at the very least a screenshot) and explain in a bit more detail what's not working?

[trombe]

Hi Reviteers

Why do I need to put my walls outside the core boudary to make the walls wrap?
The walls & the air barrier should be the core of the wall but when I do that the walls don't wrap.
Maybe I'm missing something can any one help understand this please.

Thanks

Hi Mark,

Do a search on Wall Wrap etc for a variety of answers and clarity which will answer your queries.
BeeGee and others have also explained this well.
Also read the Revit documentation about wall layer priorities since this is the correct way to approach the issue of getting wrapping to function as you expect (inserts and ends).
The documentation is cealr about what to do and makes sense in the real world of construction ( notwithstanding theat in 8.1 there may be some issues with wall joins )

good luck
trombe

[beegee]

Hi Mark,

Revit is built to follow certain assumptions ( to be intuitive ).
Most of the time this works to save users time and effort and we get to the point of not even thinking how clever the program really is.

One such assumption is that only layers can wrap.
This makes sense for a lot of wall conditions, but not all. A cavity masonry wall is one example where this logic breaks down.

Does defining the core as either just the air gap, or as one skin and the air gap, cause problems for your design ? If it does, you could consider adding a small piece of single skin masonry to the end wall to create a closure.



Hi Reviteers

Why do I need to put my walls outside the core boudary to make the walls wrap?
The walls & the air barrier should be the core of the wall but when I do that the walls don't wrap.
Maybe I'm missing something can any one help understand this please.

Thanks

[rubidge]

Mark,

Revit is most impressive, and certainly looks like the future of Architectural practice. That is why I am still lurking on this group.




Does defining the core as either just the air gap, or as one skin and the air gap, cause problems for your design ? If it does, you could consider adding a small piece of single skin masonry to the end wall to create a closure.

Its a pity to have to draw 2 (or 4) extra walls for each opening. If the wall has finishes on both sides you will have to use 2 wall types, split in the middle so that both finishes wrap into the opening.

[dirk.cilliers]

Hi Lloyd

I find in cladding a wall it works even better by just adding a second wall as cladding to a existing wall. As i never clad the complete wall any way and in this way you've got more control on the profile of the cladding. I dont see this as a drawback at all. This way you can dimension everything an all walls wrap.:)

[rubidge]

I find in cladding a wall it works even better by just adding a second wall as cladding to a existing wall. As i never clad the complete wall any way and in this way you've got more control on the profile of the cladding. I dont see this as a drawback at all. This way you can dimension everything an all walls wrap.:)

Thanks Dirk,

What happens to the cladding wall at openings?

And,

How would you go about showing a plastered wall, or a wall with tiles? For a detailed room layout (1:20 or 1:25 scale for joinery etc.) I would want to show plaster in plan, and in the wall elevations. Would you draw a 20mm wall alongside your cavity wall?

Or do you ignore plaster and draw an offset line in those views only?

[SkiSouth]

Mark, obviously you know you can wrap outside the core from your question. Just curious, why is this important to be outside the core? Apparently you have either a neat idea you're trying to work or a wall assembly issue. Spill the beans, man - tell us what you're up to...

[Mark Vorstenbosch]

HI Skisouth

No I have nothing special.The question was asked because the structure of the wall should be the walls and the Aubrie as the core but if you put the walls on the out side it becomes your finish.This was a discussion in our office that is all.

But thanks for everyones help on this post.

[davidwlight]

I'm not sure whether I've totally understood the issue in this thread, however you may want to try this......draw two walls, say 50mm apart, join them using the join geometry tool, place a door & it cuts across both pieces of wall. You will still need to add in the small pieces of wall to close the cavity. Also, you may need to adjust your door family for this to work.

[SkiSouth]

I guess stacking layers doesn't work in this project?

[irneb]

This is the DEFAULT method of drawing a cavity wall at 1:100 scale (not the Revit default, but the Architectural default even when drawing by hand) See the attached "brick as finish" method of making this happen in Revit.

As shown, there's problems with brick / block skin as finish. Possibly the only one that works in all instances is as per a previous post: adding a single skin of brick / blockwork to the reveals of each window / door. Then of course also adding a lintel / cill - but this you can do inside the door / window family. It would have been nice to be able to place a wall reveal inside the door / window family (in order to make the above automatic), but Revit disallows placing a 2nd or 3rd wall inside a wall based family & you can't join geometry to the existing wall if you've got an opening.

Then of course when creating more detailed views (say 1:20) you may want to start showing the DPC & insulation as well. This I suggest making as a detail component inside the door / window family.