Why you should insist on 3D design, not CAD from your architect

Wright at the drafting table

Clients often ask if I use CAD (computer aided design).  It’s really the wrong question- you should ask, do I design in 3D?  CAD started many years ago, and replicated the traditional method of drawing lines by hand, on a computer.  When you see cool 3D animations on HGTV, that’s not CAD, that’s 3D design.  The difference is that in CAD the architect is drawing a picture of a house, in 3D design, they are creating a 3D model of a house that can be viewed from any angle, rotated, and explored inside and out.Any architect over 40 learned to draw by hand with pencils, tracing paper, and lots of erasers.  Some made the transition to CAD, using a computer to replicate what they had done by hand.  Few, however, have learned 3D modeling.  Of course many great houses were designed by hand, including those by a fellow named Frank Lloyd Wright.

So why is 3D design necessary? To start, houses are 3D objects, they would be tough to live in otherwise.  A house drawn in 2D cannot simulate depth.  2D drawings consist of three types: Plan (bird’s eye view) Elevation (looking straight at the house), and section (cutting a slice through the middle).

Plan View
Elevation View
Section View
3D View

Here’s a 3D image of the same house:

Clearly, the critical difference is the ability to see depth- no we can understand which parts of the building are in the foreground and background.  In the past, Architects got around the problem of 2D elevations by doing perspective drawings.  Here’s a beauty by FLW:

Watercolor rendering by FLW

What is lacks in photorealism it gains in artistry.  But here’s the problem- it probably took Frank or one of his talented draftsmen over a day to produce this rendering.  What if you want to make changes to the design?  Move a wall?  Change the window arrangement, or the roof pitch? Time to get out the erasers!  The fact is, these renderings were not meant to be a design tool, they were produced when the design was done and no further changes were to be made.  It is simply not cost effective to produce hand-drawn perspective images throughout the entire design process.

Who cares?  You the client should care, because without 3D you are essentially in the dark during the design process, with no way to really visualize what the house will look like.  Ideally, design is a collaboration between the designer and the client.  3D design enables the designer and client to iterate in real-time.  “What would it look like with three windows instead of two?”  Let’s add a window and see.  “Would the kitchen cabinets look better painted or wood?”  Let’s find out.  3D allows the client to be a full participant in the design process.

So your architect does 3D, you’ve seen renderings on their website?  Maybe…  As I said, most architects over 40, which is basically any architect worth hiring, learned to draw by hand, and most never made the switch to 3D design (actually called “object oriented programming”).  They have a younger person on staff who does the 3D work.  This is problematic for two important reasons-  First, the architect is not using 3D as a tool for visualizing the building as they design.  They are drawing in 2D and visualizing the actual 3D building in their mind’s eye.  This can lead to expensive mistakes when it comes to the actual construction, as things they may appear to work on the drawing are impossible in real life.  More importantly, they are not able to collaborate in real time with the client, because they themselves cannot do the 3D modeling.  Want to see three windows instead of two?  “I will give it to staff, and we can meet next week to review”.  This type of cumbersome, expensive process inhibits true collaboration between client and architect.   Bottom line- if you want to be part of the design process, hire a designer who personally uses tools that enable you to visualize changes in real-time.

Labor of Love

Contemporary Lincoln House
A house I designed and built in Lincoln for my family is for sale by the current owner

I just discovered that my baby (the house I designed and built for my family) is for sale, so it seemed like a good opportunity to write about it. There are some nice pics and an excellent video here.  The story begins in Lexington.  We were living in a Victorian that I had gut-renovated, with a West-facing water view in a great neighborhood.  So of course I wanted to move- it’s the architect’s curse, always wanting to try the next thing.

Renovated Victorian with large windows.
Our previous house was a Victorian I renovated, with lots of windows facing a sunset/water view.

We found a piece of land on an idyllic dirt road in Lincoln MA- the hotbed of modern architecture. In fact, my neighbors on each side were architects!  The land had a Deck-type house on it that we considered renovating, but ultimately decided to build new.  There was enough room on the lot to live in the existing house while we built the new one about 3’ to the side.

When I saw Hawk Hill Road, it was love at first sight
When I saw Hawk Hill Road, it was love at first sight
There’s nothing more exciting than laying out the walls for your new house!
The new house rises behind the tired old Deck house
The new house rises behind the tired old Deck house

I went through many iterations of the design, starting very far from where I ended up.  The main challenge was the siting of the garage on the corner lot.  I didn’t want the garage to be a focal point, but I also didn’t want a long driveway to access it.  While walking the dog one day I had a Eureka moment- I could put the garage under the house and access it from a different road.  That led to a design that allowed the house to cascade down the hill, following the slope of the land, with the garage essentially invisible.

The next challenge was figuring out how to get light and views into every room, particularly the kitchen where we spend a lot of time (hazard of having a home office).  I realized that the only way to get light in the morning and evening was to put the house on a north/south axis, and make the kitchen/breakfast room the full width of the house, so it would get eastern and western light.  This led to a long house that moves up and down, and in and out, as needed for the various requirements of each room.

Then came the roof.  My original concept was to have a series of geometrically shaped forms, like pyramids and cones.  As I was working on the computer model, I had the roof layer turned off, so I could look at the building walls without seeing the roof.  My wife wandered by and said “I didn’t know you were going to do a flat roof”.  That was the second Eureka moment- I didn’t need my little “village” of roofs- there was enough happening with the different floor levels and cantilevers.  Making the roof flat emphasized the horizontality, and tied it more successfully to the site.  Thus goes the design process.

west small
West view showing the seven different roof levels that follow the sloped site

I built the house mostly with my own hands, with the help of some additional carpenters.  The framing was a hybrid of stick-built and modular, and I knew it would be hard to explain to contractors.  We built the walls flat on the deck, including the siding and windows, and then lifted them (sometimes with the help of a small crane) into place.

Lifting the walls into place using a pulley, come-along, and a convenient tree.

The weather was the biggest challenge- it seemed to rain every day that spring.  I finally decided to cover the entire building with a gigantic tarp that was 75’ wide and 200’ long, and weighed a million pounds (maybe not that much).  It took four men two days to build a series of masts and cables to hoist the tarp onto, just in time for a huge storm.  I watched with satisfaction as torrents of rain ran down the tarp onto the ground, rather than soaking my new floors.

The big tarp in all its glory before the storm came

Then the wind picked up.  The tarp started to billow like a giant spinnaker.  The wind increased to gale-force gusts and the hail started to fall.  A freak storm had come to visit.  The billowing tarp was now fully inflated like a spinnaker in a tail wind.  To my horror, the uplift forces actually were trying to tear the building upwards, off the foundation.  I had visions of the entire building sailing down the street and landing on a neighbor’s house.  It also started making terrible groaning sounds, like a ship in heavy seas.  There was no choice but to leap into the fray with long knives, slashing the tarp like pirates attacking a sailing vessel.  As we cut away the tarp, the booms that had been holding it started swinging wildly, threatening to decapitate us.  It was an exciting forty-five minutes!  I was left with four days of wasted labor, and a spaghetti matrix of tarp fragments, splintered wood, and cable wrapped around everything.  Note to self:  Do not cover a large building with a tarp if gale-force winds are expected. On the positive side, I had kept the building somewhat dry during the storm, and I had enough tarp material left (after much cutting up and drying off) to cover my lumber piles for the rest of the job, and then some.

There are many custom design features in the house.  The downside of being able to having complete creative freedom on your own home is that you have complete creative freedom.  Where to stop?  The wheel was reinvented many times during the design and construction.  For example, I wanted the clerestory windows on adjacent sides of the family room to be continuous, without any visible joints between window units.  That meant site-fabricating all the clerestories, and sandwiching custom-made steel plates into the window frames to support the roof load.  It’s the kind of detail that probably no one else would care about, but since I was going to be looking at it every day I had to get it right.

transom window
Thin pieces of steel are hidden in the vertical window muntins to support the roof above

Another interesting detail was the siding.  I’m a big fan of MDO plywood and have used it for many years.  It is basically impervious to water, and holds paint incredibly well. The weak link of using plywood for siding is the joints.  The vertical joints are no problem, but horizontal joints are tough to keep water out of.  So the trick was to get really long sheets, but they were not available on the East coast.  I found a mill in Oregon that would produce custom 4×12’ MDO sheets, since I was ordering a couple hundred pieces.  However, they would not ship east of the Rockies.  After about a week of phone calls, I arranged a byzantine route of three different freight companies that would somehow get it here.  And it did arrive, one night about 9pm, an exhausted tractor trailer drive knocked on my door saying he had a delivery but couldn’t find the warehouse where he was supposed to drop off the material.  He was not thrilled to learn that he was in the right place, and that he and I would spend the next three hours unloading the truck by hand in the dark.  That’s where cash can be a great motivator.

Custommade 12' long sheets of MDO plywood eliminate horizontal siding joints
Custommade 12′ long sheets of MDO plywood eliminate horizontal siding joints

I wanted to cover the siding joints as minimally as possible.  I decided to use 1/8” thick by 1 ½” wide strips of aluminum, which would be more durable and straighter than wood battens.  I didn’t want visible fasteners, so I ended up using 3M’s VHB (very high bonding) tape.  3M is not engaging in hyperbole when they say it is high bonding.  We would apply the tape to the aluminum batten, and then press the batten onto the MDO seam with a roller.  Occasionally we would put a batten in the wrong place, or it would be cut slightly wrong and we would need to replace it.  Forget-about-it.  That tape is so strong that driving a crowbar between the batten and plywood would actually result in tearing the plywood apart- that tape was not letting go.  It’s used to hold those giant mirrors over your head in the tunnel at O’Hare airport.

Applying the VHB tape and installing the aluminum window trim
Applying the VHB tape and installing the aluminum window trim

Besides structural details, there were countless aesthetic details as well where I wanted to try something different.  In the master bath, I thought it would be cool to have a starlit ceiling over the tub.  I had used fiber optic lighting on other projects, but typically it was in a bedroom where I had access to the ceiling from the attic above.  With the flat roof, I had to figure out a way to do all the wiring from below.  Suffice to say it is not easy to connect one hundred fiber strands into tiny holes while balancing a sheet of plywood on your head.

Fiber optic starlights in the blue (night sky) ceiling twinkled and changed color. How romantic!

In the interests of keeping this post from becoming a novel, I will save my descriptions of other details for future posts.  Suffice to say that I hope my baby gets a great new owner who will love living there, even if they don’t have the intimate connection to a house that there person who designed and built it has.  And finally, who can resist a picture of a kid in the bucket of an excavator?

My son when he was still young enough to allow me to take pictures like this
tear down
There were some anxious moments as the excavator tore down the existing house within inches of the new one. Particularly when the chimney started falling in the wrong direction…