Take a look at the discussions on JLC Online's
computer solutions forum and you'll find
the perennial CAD thread called something like "Chief vs.
SoftPlan vs. VectorWorks vs. Cadsoft vs. AutoCAD vs.
whatever else." By now, everyone should realize that if
you're willing to spend a grand or more, you can purchase a
license to a full-featured, professional,
architectural-specific 2-D/3-D CAD system.
But what if you do design work only occasionally, or need only
basic drafting capability? Simple room additions, decks,
built-ins, and the like still require thorough and accurate
design, but do they warrant purchasing a high-end CAD system?
And what about the claims of "instant material lists"—
can you trust any of them?
In the January 2001 issue of JLC, I took a look at several
low-cost and no-cost design systems and concluded that if you
were willing to learn how to use multiple products — one
for 2-D drafting, another for 3-D visualization — and
then endure some annoying work-arounds, you could produce
acceptable client work with software costing a few hundred
bucks or less.
This time, I wanted to skip the work-arounds and find options
that would provide a decent end-to-end design solution on a
reasonable budget. I originally set the bar at around $500, but
quickly found that I was a couple of hundred bucks low.
However, I was able to find capable 2-D/3-D packages for under
a grand.
I focused on the three general functions a JLC reader might
need: 3-D presentations, working drawings, and CAD-assisted
estimating. With those functional areas in mind, I spent the
last few months soliciting, installing, and testing dozens of
CAD products.
The vast majority were too generic or too simplistic, or
required a rocket scientist to figure them out. So for this
roundup, I settled on four product families: Cadsoft's
Envisioneer and little brother 3D Home Architect, DataCAD LT
11, IntelliCAD plus ArchT, and the wild card — SketchUp
Pro. Not all of them satisfy every one of my three functional
criteria, but they are all worthy additions to your digital
toolbox if you accept their limitations.
3-D Presentations
I wanted the ability to quickly and accurately create a 3-D
model of a project for sales presentations or to clarify
construction details. Back in 2001, I suggested using an image
editor like Paint Shop Pro or Photoshop to patch up whatever
the low-cost CAD couldn't handle, and that is still an option.
But this time around I was looking in particular for something
I could use in real time while sitting face-to-face with
clients, with no fudging.
SKETCHUP
DATACAD
SketchUp is unique in 3-D design because
you draw directly in 3-D space, the same way an artist would
sketch on paper. Most 2-D/3-D CAD is more like DataCAD; it
forces you to work in a 2-D view, and then generate 3-D in a
separate window.
It's not critical that the 3-D model be accurate to the inch
(unless you intend to extract your bill of materials or "slice"
your 2-D drawings from it), but the software does need to be
flexible enough to draw whatever it is you're planning to
build. The ability to create a custom-turned bun foot on a
kitchen island, for instance, will be a whole lot more
important than whether you get 2,500 different 3-D shrubs or
800 carpet patterns, as you do with consumer CAD
products.
Can you add exposed rafter tails, or are you stuck with a flat
soffit? What about an oddball-sized gable dormer with a
different pitch than any other roof on the building, a
trapezoidal window above the plate line, or a complicated
built-in under the stairs?
Of the products reviewed here, SketchUp is by far the king of
working directly in 3-D space. 3D Home Architect and
Envisioneer both let you add and edit items in 3-D (initial
drawing is done in a 2-D floor-plan window), while DataCAD LT
and IntelliCAD/ArchT are more old-school: You do most of your
drafting in a 2-D window and have to load a 3-D generator to
see the results.
Working Drawings
Although 3-D may rule for presentations, the job site still
runs on flat drawings. Unlike generic 2-D-only CAD,
builder-specific 2-D/3-D should give you a running start on
your working drawings by allowing you to create automatic
elevations and building sections from your 3-D model, and then
use built-in 2-D CAD tools and notes to dress them up for
construction drawings.
Good working drawings — like this
one produced in IntelliCAD — require the flexibility to
determine how dimensions appear, manage line weights and layer
visibility, and print multiple scales on the same
sheet.
All of the products reviewed except SketchUp and 3D Home
Architect have precision 2-D capability, and even SketchUp can
give you rough elevations — as well as sections and floor
plans — by simply slicing the 3-D model. 3D Home
Architect has no 2-D drafting capability at all, making it
practically worthless for working drawings, but it does allow
you to add dimensions to floor plans and notes to various views
for presentations.
Conflict checking. We've all had that
set of plans where the ductwork runs through the skylights
because somebody didn't bother to check drawings for
consistency. Even if you're starting from a very complete 3-D
model, these errors can still occur with 2-D/3-D CAD unless you
can overlay your floor plans in some way to check for
conflicts. DataCAD LT, IntelliCAD/ArchT, and Envisioneer all do
well in this regard.
SketchUp sidesteps the problem: You draw the entire model in
3-D and then slice it to create the flat drawings —
which, if you've drawn a complete model, makes conflicts more
obvious.
Dimension options. At a bare minimum,
2-D CAD features should give you the ability to draw quickly
with precision and apply "associative dimensions," which update
automatically when you move something. You also should be able
to apply extension lines and dimensions from both the center of
objects (for window placement in a wall, for example) and the
edges of an item (for dimensioning a building to face of
stud).
There should be a way to save reusable 2-D symbols (or
"blocks") so you don't have to reinvent the wheel with every
drawing. Every product in this review has some kind of symbol
navigator to make it easy to add your saved items to a
drawing.
And finally, for bonus points, you should be able to print
multiple drawings at different scales on the same sheet, say a
floor plan at 1/4 inch = 1 foot and a cabinet detail at 1/2
inch = 1 foot. Of the products in this round-up, only the
IntelliCAD/ArchT bundle has that capability.
CAD-Assisted Estimating
Everyone wants the ability to generate an accurate bill of
materials based on CAD drawings, something every $30 "design"
package at the big-box office supply claims to do. But for this
feature to be useful to a contractor (and not just a toy for a
homeowner), five things have to be true:
• The objects on the drawing must represent reality (the
wall you're drawing must have all the attributes of the wall
you will actually build).
• The software must be able to accurately count and report
what's directly on the drawings (the LF of wall, or the number
and type of shower units or exterior doors).
• The software must be able to calculate, or
"extrapolate," related materials to your specifications, based
on known quantities of other items. You might use more or less
rebar in your foundation than the next guy.
• You have to be able to define those items. "Tubes
Construction Adhesive" and "Boxes Gun Nails" don't mean a thing
unless you know they're quart tubes and 5,000-fastener
boxes.
• Finally, you need to be able to get a bill-of-materials
(BOM) report out to Excel or some other estimating
software.
None of the consumer-related CAD programs I tested, including
3-D Home Architect, could fulfill all of those requirements.
They could count but not calculate; or they could calculate but
wouldn't allow me to change what was being calculated —
for example, the materials that I wanted to use in a 2x6
wall.
Envisioneer's configurable materials
database makes it one of the best CAD-assisted estimating
products available today at any price.
Like more conventional 2-D CAD programs, SketchUp Pro can count
and report on the number and type of components in the model,
but since you're not defining objects for walls, framing, and
so forth, a basic window or fixture schedule will be the best
you can do, and that will require programming.
IntelliCAD/ArchT creates the lists and counts, but requires
third-party estimating software (or a good programmer) to
actually get the information out into a usable report.
Of the packages in this roundup, only one — Envisioneer
— shines in the estimating realm, with a fully
configurable materials database and complete flexibility about
how those items take off from the model.
Joe Stoddardis a technology consultant to the
building industry and moderator of the JLC Online computer
solutions forum. You can reach him at
www.mountainconsulting.com.