Wednesday, July 8, 2009

Is Revit faster than…

I’m SO tired of the questions/observations/comments on the speed of Revit in delivering a project. Is Revit faster than <insert drafting software here> (AutoCAD, AutoCAD Architecture, etc., etc.?) I thought Revit was supposed to be faster than CAD… It takes forever to <insert modeling task here> compared to CAD.

Seriously? Which is faster?


World's Fastest Jet

Or this?

World's Fastest Hard Drive

Don’t get the connection? Me neither.

Both of the items pictured are (debatably) the fastest at what the do.

How fast does a SR-71 Blackbird transfer data? Depends on how far away the transfer points are and how much and what is the format of the data.

How fast does a Seagate Savvio 15K drive fly? Depends on who throws it.

Revit and CAD are as similar as a Super Sonic Jet and a Hyper-fast Hard drive. They do (or produce) different things.

Let’s compare apples to apples, or at least to fruit to fruit.

First on the individual “task” level.

Ex: Placing a wall in Revit vs drawing a wall in CAD.

Now I would argue that it actually IS faster for me to model a wall in Revit than it is for someone to draw to lines and a place hatch pattern in AutoCAD (maybe you could keep up if you had a tool that placed all that at the same time, hmmmmmmm, isn’t that AutoCAD Architecture (I won’t go there.)) But let’s just say for arguments sake, that it WAS faster in CAD (a stretch I know.)

OK, now show me an elevation of that wall.

Revit: DONE!

CAD: Draw rectangle>fill with hatch>DONE! (HA, not so bad.)

How about a section?

Revit: Click, Click>Done.

CAD: Rectangle, Fill with hatch (Sounds familiar.)

OK,OK. Now a building made out of those walls. Keep it simple. Single story, flat roof, “office park” building.

Time Elapse, everyone’s done.


Revit: Select type>place>place>place>etc., etc.

CAD: Place block (even a “smart” block)>Trim wall>Trim Wall>Repeat.

Wait, move that last door 6”?

Revit: Sure. Move.

CAD: You bet. Move>Trim>Extend>Fix Hatch

Ummmm, 10’ walls won’t cut it, change them to 12’.

Revit: Change elevation of Top Constraint level.

CAD: Redraw 4 elevations (for a box shaped building) oh wait, almost forgot the section.

You know it would be great if I could see that in an Isometric.

Revit: No problem. Click

CAD: Why? We never did that before… I mean, sure. Give me a couple of minutes.

You know, it looks kinda dumpy with that flat roof, how about a simple Hip?

Revit: Got it, like this? Sketch 4 lines>Define Slope>Finish (Section, infinite elevations, 3d/ISOs) Done

CAD: Umm, yeah, I just gotta get the is ISO done. Then I can update all the elevations, the sections, oh geesh and that ISO. Come back tomorrow? (Faster huh?)

Could you guys do an energy analysis on that?

Revit: My Mech tech an export that to Ecotect or Green Building Studio and get you something in a few minutes.

CAD: Ehhh? on… lines…? Hmmm, Ummmm…. What the heck is that Revit guy doing over there? Walkthrough? What? C’mon…

Ok,OK, enough of this. The point is, if you are using CAD to produce Construction Documents and you want to replace drafting with 3D modeling in Revit CAD may (debatably) be faster.

If you want a tool that allows you to investigate and communicate design intent (sometimes, with an Ace user,) in real time. If you want a tool that you can then leverage that model to do energy analysis, Sustainability analysis (based on materials in the model,) Visual and Location based construction sequencing (4d,) Model based Quantity Take Off (QTO) then Revit (or, admittedly, some other BIM authoring tool) is faster. In some cases it’s the ONLY way.

Stop comparing your old, worn out tools and processes to my cutting edge, efficient project delivery method.

And stop trying to use my new tools the way you use your old one. If I buy a new table saw to speed up building my house, and you pick it up, turn it over, and try to run it across a sheet of plywood… at best, it’s slower and less efficient… at worst, somebody’s gonna get hurt. And nobody’s to blame but you.

This BIM thing is more analogous to Building a structure than Drawing it. Evolve, or become extinct.

Remember, "It is not necessary to change. Survival is not mandatory." - William Edwards Deming


Anonymous said...

Will - that was hillariously accurate. The only thing I have to complain about is that you didn't tease architects quite enough. Now if only I could get management to realise all this and change their thinking. Old habits are hard to break sadly...

Erik said...

Not sure who posted that last comment, but you're right, getting management in board is SOOOO important. And BTW, my name is Erik, not Will. ;p

Anonymous said...

Sorry about that Erik, I just read the quote at the bottom and thought you had signed the article (ie. didnt realise it was a quote until now)
As a drafter Revit makes life so much easier - of course more time is spent getting the model just how you want it, but once it's perfect, infinite sections, views and details are instantly retrieveable...The true power lies beyond the make-up and lipstick of the 3d model that WOW's the client. I always reap the rewards later when the architect decides to change a door layout in a lift core for 70 levels...instead of redoing 13 pages of elevations in CAD - change the plan locations and all else is DONE...CAD can simply not compete on larger scale projects.

David said...

Just found your blog. I love it. You even closed this post with a quote I have used countless times during this transition to Revit MEP. I think your my new hero with this post.

David Raynor

Mark P said...

Hi Erik, I just ran across your post. I've used acad since v12 and have been learning revit for a couple yrs now after learning autocad arch' (arch desktop) yrs ago, which was a waste of time. I stopped using acad arch' bc a. it's hardly being used in aec that i've seen and b. it's way too cumbersome. I admit there are frustrations w/revit that i could just cheat with (i am still learning) in cad to get that view done and move on but all in all revit is wizardry. =) Being faster is great but the mere fact that it ripples through the entire CD set w/out worries is priceless. I've seen countless examples of 2d lines in hap-hazard places and mistakes done by other drafters when passed on to me in cad and i've wanted to pull THEIR hair out.
Fantastic quote by Deming too.