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The KISS Principle

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KISS is an acronym for “Keep it simple, stupid” as a design principle adopted by the U.S. Navy in 1960. The KISS Principle states that most systems work best if they are kept simple rather than made complex; therefore simplicity should be a key goal in design and unnecessary complexity should be avoided.

The principle most likely finds its origins in similar concepts, such as Occam’s razor, Leonardo da Vinci’s “Simplicity is the ultimate sophistication”, Mies Van Der Rohe’s “Less is more”, or Antoine de Saint Exupéry’s “It seems that perfection is reached not when there is nothing left to add, but when there is nothing left to take away”. Colin Chapman, the founder of Lotus Cars, urged his designers to “Simplify, and add lightness”. Rube Goldberg’s machines, intentionally overly-complex solutions to simple tasks or problems, are humorous examples of “non-KISS” solutions. [you know where]

As the result of reading The Autopoiesis of Architecture, I’d like to add “theory creep” to describe situations when architectural theory uses reasoning of maximum complexity to describe realities with profoundly simple drivers. The theme of this post however, is to explore the meaning of simplicity in architecture. Mies’ dictum “Less is more” was quoted above as an example of simple being better. I disagree. Edith Farnsworth disagreed.

The lighting of the fireplace on the hearth revealed a curious fact, namely, that the house was sealed so hermetically that the attempt of a flame to go up the chimney caused an interior negative pressure. This was surprisingly hard to correct.

Hmm. It’s the function of a fireplace to produce radiant heat and some warm air, some of which unfortunately has to escape up the chimney. This benign little focal point is hardly a Wrightian hearth but apparently it could suck all the air out of the house. But I wonder how they noticed the negative pressure? Did they see panes of glass bow inwards at nighttime?

Fireplace (Photo credit: anneh632)

There is a chimney however – fan-assisted? In the above photo you can see how the mechanical room is full height. This mechanical room is crammed with stuff, apparently. [thanks farnsworth51!]

Planof-Core-1024x580 (1)

Finally the travertine floors were complete, the furnace room was loaded with the boiler for the floor heating coils and two hot air furnaces as well as the overhead water tank, and the “core” was surrounded by a light wall in paneled wood veneer. It was at this point that I found that the utilities had been jammed together so ruthlessly that only the most emaciated of heating and plumbing men could open to service the equipment lying to the east of the middle. As for the chimneys and dampers for the oil furnaces, they could only be reached by the plumber’s oldest boy, a thin wiry child who could be poked back among the pipes and was just old enough to carry out orders. [same place]

I guess problems with the fireplace updraft don’t matter that much when you have underfloor, oil-fired, heating coils and two ‘hot-air furnaces’.


I wonder where the oil tanks were? From where did these fans suck and blow? I’d love to see a section through the mechanical room. This section through the guest bathroom shows that the overhang space that creates the fireplace in the living room belongs to the bathrooms. You can see it in the photo coming up.


The drawing states that the bathroom wall finish is painted plywood (including the shower, incredibly). You can see it here in what is probably the only photograph of the mechanical room you are ever going to see.


This core and drainage plan shows that the pipe in the middle is the soil vent pipe.

core plan

I expect the boilers have been replaced with tiny condensing boilers and there’s a lot more room in here these days. It also shows the core structure, for what it is, but not why that shaft containing one pipe (roof drainage?) has to be on the side of the master bathroom and offset from the combined utilities/sewerage point on axis with the fireplace. There must be something else happening in there but what could be so important to make the main bathroom smaller than the guest bathroom? One thing is for sure, from looking at this photo of the master bathroom, [valogianni] that extra foot makes a difference.


Both valogianni say the same thing about the matter of thermal comfort.

As regards thermal comfort, the Farnsworth House performed poorly before the implementation in the 1970s of corrective measures. In hot weather the interior could become oven-like owing to inadequate cross-ventilation and no sun-screening except for the foliage of adjacent trees. To create some cross-ventilation occupants could open the entrance doors on the west and two small hopper windows on the east, and activate an electric exhaust fan in the kitchen floor, but these measures were often inadequate. In cold weather the underfloor hot water coils produced the pleasant heat output characteristic of such systems (partly radiant, and with temperatures at head level not much higher than at floor-level), but insufficient in midwinter.

Underfloor systems also have a long warming-up period that is ill-suited to an intermittently occupied house. To increase the supply of heat, and give quicker warming, hot air could be blown into the living area from a small furnace in the utility room. There was also a somewhat ineffective fireplace set into the south face of the central core, facing the living area, which it is said to have covered with a layer of ash.

The worst cold-weather failing was the amount of condensation streaming down the chilled glass panes and collecting on the floor – one of Dr Edith Farnsworth’s complaints in the 1953 court case as described on p.15. This was an elementary design fault whose consequences Mies must have foreseen and could have avoided, but presumably chose to ignore so as not to destroy the beautiful simplicity of his glass-and-steel facades.

Here’s a window detail, in all its beautiful, thermal-bridging simplicity.


Or, if you prefer a 2-D. That’s all steel, baby!


You can find more construction details here. And here. This next photograph shows the relationship between the services conduit below, the utility room and the chimneys. The rooftop box not visible in the original sections, must be the A/C system installed in the 1972 renovations. Beneath the house you can see the cover for the conduits and pipes that get the water and electricity in and take the shit away.


All this visible simplicity requires a lot of invisible complexity to make it work. Or, to get  closer to the truth, all that invisible complexity needs a helluva lot of tangible $ to make it work. And even the visual simplicity needs some tangible dosh too. How much money do you think it takes to make this kitchen counter out of a single piece of stainless steel, for example? It’s odd how the entire surface to the left of the cooker is a recessed “drainage board” for the sink. It looks fussy and contrived. Ironically. 


I was trying to accomplish a bit of economy in connection with the hardware that day. “I can’t believe that that single door handle has to be made to order and to come from some far place. Sometimes I wonder whether the boys know how to shop for such details.” [EF]

Edith Farnsworth’s journals also have something interesting to say about the flashing at the parapet.

farnsworth details

But let’s go back to the terrace. Architectural Guidance has this to say.

The travertine-paved terrace has a perfectly level upper surface and yet remains dry [!?]. This has been achieved by laying the slabs on gravel beds contained in sheet-metal troughs with water outlets at their lowest points. Rainwater therefore drains down between the slabs, through the gravel beds and out via the base outlets.


This next image is two (combined) longitudinal sections along the building.


The upper section for the main level is taken along the line of these drains you can see in the image below.

Farnsworth House, Plano, Illinois-11
Farnsworth House, Plano, Illinois-11 (Photo credit: 24gotham)

The lateral cross section looks like this.


Got it? The slabs sit on sand and gravel-filled V-shaped boxes that slope towards each end where they drain. Hopefully. At you can read about the ongoing quest to maintain and repair this house. Their job is not made easier by the house being periodically flooded. For one, the floodwaters waterlog the mortar under the travertine and in winter this causes a problem with ice heaving which then causes a problem with …


Our second pre-winter project is an effort to determine the level of saturation in the substrate below the travertine of the exterior surfaces. The plan here is to remove 15 travertine pavers and the mortar and gravel below them. We will then perform a complete inspection of the moisture retention and the damage caused by frequent high water and this most recent flood. Ideally, we would remove all of the exterior pavers prior to the winter freeze but this project is expensive and we must seek funding mechanisms before proceeding.

The problem with the water NOT DRAINING is being caused by the DRAINAGE detail, stupid!

* * *

The KISS Principle was

reportedly coined by Kelly Johnson, lead engineer at the Lockheed Skunk Works (creators of the Lockheed U-2 and SR-71 Blackbird spy planes, among many others).

The principle is best exemplified by the story of Johnson handing a team of design engineers a handful of tools, with the challenge that the jet aircraft they were designing must be repairable by an average mechanic in the field under combat conditions with only these tools. 

The acronym has been used by many in the United States Air Force and the field of software development.

It’s easy to see how simplicity in software is a good thing, and not only for reasons of elegance. CAD packages, for example, are particularly vulnerable to incremental add-ons that ultimately reduce efficiency and become ‘bloatware’.

And when there was once this thing called the ‘space race’, the US went for complicated liquid fuelled rockets while the USSR went for solid fuel. Each had their advantages and disadvantages. The liquid fuel rockets could be shut down at a later stage during the launch sequence. The solid fuel ones were essentially big fireworks but, importantly, they were cheaper, were more reliable because they had fewer parts that could go wrong, and they did the job. For a while, they were the only rockets in service.

22 Dec. 2016: My apologies to everyone and thanks to Victor for providing the following clarification even though it’s almost four years since the original post. I’m including it here in the body of the post rather than as a comment that may be overlooked.  
“As to my knowledge, this suggestion only applies to ICBMs, which are not clearly a space race and more of an arms race, despite them escaping the atmosphere for a little bit. Both countries fed off German heritage they stole, with US having Von Braun himself and Russia with Korolyov reassigned from a tundra gulag branch into a moscow design bureau for imprisoned engineers whom you don’t have to pay and can speed up with death threats gulag branch. V-2 used ethanol plus oxygen. Everyone’s first thing in space program was to build a replica of V-2. US must have made it too, but I would not lurk for it. So in the early stages only liquid fuel was an option and it was used in R-7, which is sort of a miracle of building a launch vehicle of turd in a pud, like it has 4 ignition chambers per engine what is heavy as fuck because they had no technology to build single powerful chamber, and the list goes on. 60 years in service. You don’t improve a redundant launch vehicle just for the sake of it. Now, Mercury rocket used liquid fuel too, except for its virgin phase test booster which was solid fuel, as guess which source reports. You can control how much liquid fuel you put into engine, what is perhaps the most essential feature for an orbital mission, not to mention a manned one. Within liquid fuel realm, there are more issues of which fuel you use. You can use that toxic nirtogen based fuel which self-ignites and also kills all flora and fauna in 5 km vicinity of crashed spent stage, hence manned mission use kerosene which is simple and stable fuel. Hydrogen delivers the biggest bang, in exchange for lean cryogenic operations with it. You already have cryogenic oxygen as an oxidizer so is it worth the trouble? You can afford cryogenic operation on a manned mission since it’s once a time and it deserves good preparation.
This is not the case of ICBMs which are better off sealed in their shaft and only taken out in 20 years for replacement. Their commissioners disliked pre-launch meddling and any other capacity for lag. So a solid fuel cartridge with warheads put atop of it won a favour and had proven itself as a sturdy thing. All guidance is performed by a liquid-fueled sub-orbit module, the missile only has to jump out of the atmosphere. You can pre-program the flight profile into the stage by cutting shapes into the fuel cartridge – with a star-shaped channel in the middle it will burn more intensively than with a simple round one.”

Failure to observe The KISS Principle is still with us. Are Boeing’s current problems with the Dreamliner just teething problems? Or are they are result of the Dreamliner’s complexity not just of engineering but also (according to this, and this) of procurement?

The Dreamliner is made of carbon-fiber reinforced plastic composite. More radically still, pneumatic and hydraulic systems have been ditched for electric systems.

The technological leap was always likely to cause teething issues. But these were exacerbated by Boeing’s decision to massively increase the percentage of parts it sourced from outside contractors. The wing tips were made in Korea, the cabin lighting in Germany, cargo doors in Sweden, escape slides in New Jersey, landing gear in France.

The plan backfired. Outsourcing parts led to three years of delays. Parts didn’t fit together properly. Shims used to bridge small parts weren’t attached correctly. Many aircraft had to have their tails extensively reworked. The company ended up buying some suppliers, to take their business back in house. All new projects, especially ones as ambitious as the Dreamliner, face teething issues but the 787’s woes continued to mount. Unions blame the company’s reliance on outsourcing.

Bill Dugovich, communications director at SPEEA, the professional aerospace union, said his members had first voiced their concerns in 2002. “Outsourcing in general lengthens supply lines, creates problems with language and culture and is extremely hard to coordinate. You have seen a plethora of problems at Boeing. Things get outsourced then they have to come back to Boeing to get fixed,” he said.

Dr Amar Gupta, dean of Pace University in New York, has studied the construction of the Dreamliner and is not convinced that outsourcing itself is the issue. “We have been outsourcing since the industrial revolution,” he said. The problem is one of communications, he argues, and complexity. A car has roughly 15,000-20,000 parts; a plane has more than 2,000,000 parts.

“The concern is that each organisation did what it was asked but there was a failure to bring the whole thing together, to integrate the systems,” he said.

My photos that I took at today's First Flight ...
My photos that I took at today’s First Flight of the Boeing 787 Dreamliner. (Photo credit: Wikipedia)



  • says:

    KISS is used in marketing messaging. That’s why most ads are (supposedly) easy to understand –– and quickly. We’re going to tour Fallingwater this spring, so I’ll be sure to note how livable it is. These posts from Misfit’s Architecture and real eye-openers!

  • Thanks for this article and thanks in general for so thoughfully puncturing the thin balloons of starchitects. The Farnsworth house demonstrates a faux simplicity that is entirely superficial. It looks like a piece of sculpture but is pretty much unlivable–just like so many other houses by famous designers who imposed their vision on some hapless family’s life. When I went to architecture school at Cal, Wurster Hall was being built with interior utilities like ductwork exposed, in an effort to integrate them into the esthetic of the building. I’ve seen it done better since but it was a start; instead of hiding some functions, integrate them into the building.

    I never have understood the drive among architects to create homes that, in photos at least, look as if they are unoccupied. Nor have I understood the drive for straight lines and flat surfaces except as a tightly-wound esthetic expression of Euclidian purity. The Farnsworth house exemplifies both. Maybe its the dream of a magically perfect life, free of hassle, drama and clutter?