Architectural Design Process | Form, Orientation and Sunlight


Hey, Eric here with 30 by 40 Design Workshop,
I wanted to talk about how architects use the Sun to influence their designs, but rather
than speak in generalities, I wanted to use a detail from a project to show you how it
works in practice. Before we get into the detail you’ll need
a little background. One of the most responsible things you can
do as an architect is to listen and that, for me, always begins with the site: the climate,
geography, wind patterns, and of course, the Sun. Architecture is nothing without light and
it’s perhaps the most important organizing force for our work. It’s usually where I start my site analysis,
by diagramming the path of the Sun as an overlay on the site plan, and I’ll get into the specifics
on how I do this in a minute. The predominant solar orientation – where
the most direct sunlight comes from – here in the northern hemisphere, is the south. So, the more of our building that can face
south the more efficiently we’re able to capture and use the Sun for natural light, and passive
heating, and even cooling as we’ll see in a minute. This approach not only saves energy reducing
lighting, heating, and cooling costs, but it’s also better for our own health and well-being. For this project, the lot was sloping and
rather long with the neighboring residents close by to the north. The views to the ocean were all off to the
east. With an east facing site like this you’re
faced with a dilemma: do you orient the long axis of the building north and south to give
the client the view of the ocean they requested – from every room – or, do you deny the
water view in favor of a more sensible solar aspect? Truthfully, I wanted it both ways. The solution I designed divided the program
into public and private wings, each oriented with their long axes east and west as you
can see here in the site plan. This gave me the long flank of the building
to collect sunlight and I could still orient some of the most important spaces, the master
suite, the living room, and a guest suite, toward the water view. The, “every room has to have a view of the
ocean” is a common request where I practice; it’s one of the main draws of buying a piece
of waterfront property obviously. But, I always try to advocate for a deeper
exploration of the site and an interweaving of the architecture into the larger whole. This site has many other features to explore
in addition to the water view. By using the circulation to stitch the building
volumes together, I could continually change the perspective as my client moved throughout
their house and their day. Arriving home they would head east and then
south and then east again and this combined with a changing horizon line and sets of interior
steps, which mirrored the sloping site, this allowed each space to capture a different
perspective on the site. Now, let’s dig a little deeper on the impacts
of the Sun on this specific design solution. The plan is laid out as three linear bars
each stepping down with the topography toward the water. An initial approach might be to simply extrude
the bar and put a flat roof on it, but this is less dynamic it doesn’t really react to
the solar exposure in any specific way. But, by picking up the southern eave of the
roof like this and adding a glazed clerestory in the void this became a really efficient
device for letting in sunlight on the southern exposure. The higher you can locate a window on a wall,
the deeper it will admit daylight into the interior. As we look at the section you can see another
solar advantage of the shed roof, it allows daylight to pass by the roof form and reflect
off the taller northerly wing. Because the private wing contained a lot more
program than the public wing – five bedrooms, a laundry, a library, and a mudroom area – we
had to design it as a two-story volume. The site analysis made it clear that placing
it to the northerly edge of the site would confer a number of advantages, it blocked
the views to the neighboring residence, it served as a wind block from the harsh northerly
winds on the site, and if we made it two stories tall we could use it to help bounce light
back to the northerly face of the living wing as you can see here. So, I’d encourage you to think about a diverse
range of uses when it comes to sunlight and how it interacts with your architecture. How can you exploit it understanding that
buildings can absorb, block, filter, consume, store, and reflect sunlight? Alright, now that you’re up to speed on the
larger design moves it’s finally time for the details. Clerestories efficiently daylight interior
spaces as we’ve said, but along with all that natural light comes solar radiation too, which
can quickly overheat spaces and make them uncomfortable, which is just the opposite
of what we’re trying to do with our design. And, here’s where the details matter. To control the light and heat on southern
exposures you’ll predominantly want to be considering horizontal elements for screening,
that’s because the Sun moves from a low altitude in the winter to a high one in the summer. Horizontal objects act like the brim of a
hat to shade the building and it’s the high angle Sun that presents the most danger for
overheating while the low angle Sun is good for us here in a cold climate, we want to
let in the winter Sun and use it to offset our heating costs. Horizontal elements can include an overhang,
a sunshade, awnings, screens, louvers, or brise soleil. Because our design was so linear,horizontal
louvers seemed the most appropriate. Now, we could have just matched the coursing
on the siding and called it good but there’s more to it than that. The spacing and depth of the horizontal louvers
can be tuned to your exact geographic location. Why not, right? This is where the Sun charts come in handy. Now, a lot of people have been asking about
these and I’ll quickly show you how they work. There are essentially four dates in the calendar
year that you care about when considering the Sun’s impact on your architecture. The solstices in December and June are the
points when the Sun is at its extreme arc, either high or low, and then there’s the equinoxes
in March and September, these are the midway – sort of transition – points between the
two extremes. To design the depth and spacing of the louver
blades you’ll want to know the altitude of the Sun at solar noon for each of the four
important dates. In this cold climate we can take advantage
of the lower angle of the winter Sun for passive solar heating and our design can keep the
higher angle hotter sunlight out in the summer. Now, there’s a really fantastic podcast by
the Australian architect Amelia Lee called the Undercover Architect and she does a deep
dive on this topic – I think it’s something like a six-part series – which covers each
different exposure and how you might treat it with your architecture how that impacts
design. Now, she’s got her North’s and South’s all
flipped around because, well, she’s Australian. But seriously, it’s really well done you need
to follow her if you’re not already. Links are in the description below. Okay, next step is to take these angles and
plot these values on your drawing. Remember the angle is above 0 degrees which
is – for our purposes – the horizon. So, naturally 90 degrees would be straight
overhead. So, here in Maine it’s something a lot less
than 90 degrees. Okay, so these are our values for the important
calendar dates and given these angles I start with some basic assumptions about my louver
design and then I begin tweaking as necessary to get the intended effect. Now, you can use SketchUp or Revit and I really
like the app Sunseeker and the real-time augmented reality especially for renovations. These tools will all help you study and understand
Sun angles much more quickly – and perhaps intuitively – than sketching it out by hand. But, for details like these I find sketching
to be the most tactile and enjoyable way to design. Now, here’s what we ended up with for our
design and you can see that it balances admitting ample winter Sun and blocking out the high
angle summer Sun. The rest of the year I tried to balance it
out and there’s some bit of magic between the spacing, material efficiencies, and the
depth of the louvers, and for that you’ll just have to play around with it to get it
right. The more materially efficient you can be,
the less expensive the Sun shading system will be to construct. Now, there are a lot of other ways we could
have done this including addressing it from the inside, but the most efficient way to
keep the overheating and glare issues from becoming a problem inside is to keep the Sun
from striking the glass in the first place and that means an external solution. Now, the last thing I’ll mention about the
solar design here is that passively heating spaces this way, it allows you to take advantage
of the stack effect too if you add operable windows up high as we did in our clerestory. As the interior air heats up and rises and
we open the upper windows it sets up a natural convective flow; exhausting warmer stale air
up high and admitting cooler fresh air down low. All the resources I used and mentioned in
this video are in the description below. I hope this helped explain some of the design
opportunities the Sun can provide. The data contained in solar charts are immensely
useful and pretty easy to divine when you know what you’re looking for. Smash that like button below if this has helped
you in any way, it tells me you stick around to the end and I so appreciate that! Be sure to follow me on Instagram for drawings,
sketches, and studio process images, if you’re not already. Cheers my friends, we’ll see you again next
time.

100 Comments

Add a Comment

Your email address will not be published. Required fields are marked *