Okay Tweeple, time for an office update. First of all, it snowed. It didn't last long, but on top of the rain for the last few weeks (one reason I haven't had many updates) this was a thorough test of the roof underlayment. It passed, yay.

Prior to this, things have been a little slow because I'm designing and waiting. Designing and choosing siding and specifying a wall stiffener that had to be made and delivered. Also, building the "world's computer" at work is a busy job, so, you know, life happens. And, rain.

My last project was to apply the final piece of roof membrane a few weeks ago in the last dry day. I had undercalculated how much membrane I needed and then had to wait for a roll to be shipped. Oops. Then I trimmed and stuck down the edges and installed temporary drip edge.

Now, to the front wall. This 12' long transom window unit is going to look awesome. Unfortunately it creates an engineering challenge. In most buildings, the walls have a double top plate across the top and also are tied to the roof rafters. These keep the wall from flexing.

In this wall, the roof is actually tied to that carrying beam above the windows, so all the load is fine. But under the windows, that piece of the wall isn't tied to anything. Here's the pic again for a refresher.

So, because I knew that wall wasn't load bearing, I only put in a single top plate. That was a mistake, but a small one. The problem is the wall flexes in and out in the middle. Imagine slamming that door, which is going to be solid, heavy, and insulated. Everything would shake.

Here structural engineers will talk about moments and torque arms. A common fix used for half walls in this situation is to run the studs through the floor and anchor them to the joists. I maybe could have done that if I'd planned ahead, but that would be hugely painful now.

Instead, I'm adding another top plate, but also I'm adding steel. Steel is awesome. Everyone should have some. I'm adapting an approach called a flitch beam to work in this case. Basically a big stiffener bar inserted into the wall.

First step, design custom piece of steel angle iron because stock angle iron isn't the right size on the legs. Draw CAD and brainstorm with steel fabricators til they figure out how to actually make it (one week). Then wait for steel to be made (10-14d). Et voila, one cool plate.

Because I'm me, I decide to break in my new angle grinder to clean up the mill finish and to add some texture for the glue to adhere to. It turns out that grinding the crap out of steel and spraying sparks everywhere is tedious but also very fun.

So then the next step is to chop out 1-3/4" of wood from all the studs in the wall. This was easier and faster than I thought it would be, even given marking, cutting with circ saw, then finishing with recip and cutting off nails. Steel is just test fit here.

Now, next step is to apply water to the wood and then glue all along the flange and the top plate of the steel stiffener. Then clamp it to death.

Polyurethane glue (aka Gorilla Glue) is awesome stuff by the way. When this cures it will be stronger than the wood itself. And it uses moisture to cure, so it's inherently exterior suitable. Finally, it foams when curing. This is a handy clamping indicator.

If you applied enough glue and clamped enough, some glue will foam out at the glue line. If you messed up, it probably won't. More clamps. This is a 12'-5" beam, I think I used 25 clamps. You can never have enough clamps.

So now the steel stiffener is glued to the wall sheathing and to the existing top plate. Because it's an "angle" (right angle cross section), it's rigid in two dimensions. The wall is already more stiff, but next I'll jam a second 2x4 plate underneath the steel (glued in).

Then the whole thing gets bolted together in a couple dozen spots. Finally we'll have one bomb-proof steel reinforced wall plate that makes a rigid box spanning from the edges of the side walls. That'll be good forever. Tomorrow the plate goes in. Tonight the clamps sleep.

BTW, it is an inevitable truth that you can't keep poly glue off your hands. Here's my hands despite gloves, changed twice. The brown spots are where glue touched. To get this off what you do is... nothing. Grow new skin, let that layer slough off. It's bomb proof.

Also, all my careful math on how much glue to buy was totally wrong. I used like 70% of this 8 oz bottle to do maybe half the beam. It's a bear to squeeze out; I got a real grip strength test. Not sure I can rescue the rest of that. Might need to buy more.