ADRIAN SMITH + GORDON GILL - WILLOW CREEK COMMUNITY CHURCH

Today we're going to be looking at the construction of Willow Creek Community Church, which is a 72,000 square foot worship facility in Glenview, Illinois.

But I think the two main reasons were: cost, it is a very economical material, and also sustainability, because with EIFS it is a light material and you're able to get a lot of exterior continuous insulation on the EIFS system. This system actually has four inches of insulation in it which exceeds what you need to do by minimum energy code. So we were able to really maximize the the R-value of the building, and we were able to get a look that was like kind of the old fashioned stucco and that was what we were going for.

There's also the brown coat below it and there's a couple layers of mesh in there to stiffen up the EIFS. Below that is the insulation and on this job we're using EPS which is a more flexible insulation. The other type you often see, the pink one, is the XPS which is a little more rigid but because of our curves, we use EPS.

The other reason you put joints is they need to apply it wet, and if they have too large of an area, and if the EIFS starts to get too dry, then the workers can't apply it fast enough to make the EIFS all work uniformly and get a good look to it when they're finished. So you have to put a joint every so often basically so the workers have a stopping point.

The metal decking needs to span in the opposite direction of the joist. So in general, when you see metal decking, you'll see the kinda ribs in the deck, and they're in the opposite direction of the bar joist. In general, if you're trying to be economical with your design, you need to keep the size of the joist in a controllable range.

So we put CMU concrete block in between the steel and that was the most economical way in a building like this to create a shear wall. It could have also been done with diagonal bracing but in this case we were able to use the CMU to form the outside wall of the building. So it did two jobs architectural and structural and it was a good way for us to solve the problem.

So we're in the process of starting to form the seating for the worship space, and it is a stepped seating that steps up in order to get the best sight lines for everyone viewing the worship service. So there's many levels of steps, and they've just started to form the top three steps you can see in the back. So they did their first pour, and they're gonna come back later and do several more pours, actually all the way to the front of the auditorium.

We're looking at the back side of the assembly for the EIFS wall, it's our exterior wall here, and you can see we've got the green board for the sheathing, and it's always important when you see that bright green, or some companies make it in yellow, you can see the bright color means exterior grade sheathing. It has some fiberglass in it, and it's more weather resistant than the interior grade drywall. And then we've got our batt insulation and our metal studs, and then there's going to be another layer of drywall to complete the assembly.

Same with the EIFS, the EIFS actually has the ability to weep water out the bottom. It is a drainable system, and that's a code requirement actually, and it helps to keep the building from having any chance of getting mold or water damage. So the gaps are there on purpose between the interface, between the two systems.