Beefy Structural Steel  ?

Beefy Structural Steel ?

The post below was sent as an issue of my newsletter, Ready for Rain.

Early in the design process, John, our architect, said something that caught my attention. He said our design would require a lot of steel. Not knowing much about engineering a house, I took it as a given for a house like ours. I assumed it was normal and expected.

Since that time, I’ve had numerous conversations with people about the house and when I bring up the steel beams, they are perplexed and ask: why do you need all that steel? In watching other houses come together locally, on the internet and on TV, the houses with steel beams seemed bigger and more complicated than ours.

This led me to wonder: why does our project require so much steel? Do we have a choice?

From the very beginning, before plans were drawn, we envisioned a roof that stretched out over the deck. This roof would be cantilevered and not have posts that obstruct the view. At the time, it seemed like a no-brainer. Why have posts if you don’t have to?

What we didn’t realize was the engineering required to make that roof a reality. The regulations for our location meant the house had to withstand winds of up to 144 mph. Without a beefy roof, a strong wind could rip the roof right off the house. Further, because it hangs so far off the house, it had to be strong and support a lot of wood.

roof right off the house

So, we had a choice. We could have designed a different house on a different part of the property. We could have had a roof that didn’t cover the deck. But that felt like compromising on the dream of what the house could be. To make that dream a reality, steel was required. 

Steel (in Green) Supporting the Roof
Steel (in Green) Supporting the Roof

We’ve now reached the point in the project where the steel beams are being placed in the roof structure, and John was right. It’s a lot of big steel.

Over the last week, the biggest and beefiest steel beam was delivered to the property and it took me by surprise. It was a behemoth: 34 feet long and a foot tall. It’s commonly referred to as an “I” beam and this one is 120 pounds per lineal foot. That’s over 2 tons of steel in a beam supported by two 4X4 steel posts.

two 4X4 steel posts

A new, long-awaited phase of the project was beginning and I came to appreciate the complexity that goes along with getting the beam in place. Because it sets the standard for the entire roof, it has to be right. Once it’s in place, the rest of the roof is constructed around it.

the entire roof

When it comes to steel, the maxim “measure twice, cut once” becomes “measure 12 times, fabricate once” because corrections are so much more difficult and costly. The builder, framer, architect, and engineer worked to get every measurement right the first time. The stakes were high.

This process started when the concrete foundation was poured and screws were placed in the concrete that will hold steel posts that support the beams. The first time I saw these, I wondered how the concrete people knew where to put the screws. Their placement seemed important and I saw no evidence of measurements being taken.

Screws Awaiting a Steel Post

This was one of the first lessons I learned about the process. The screw locations don’t matter a lot because the steel is designed around the screws and not the other way around. To get it right, the builders use wooden templates that document the position of the screws. These templates are then given to the steel fabricator so they can create a post with holes in the right places. It makes so much sense!

Two Templates Nailed to a Board
Two Templates Nailed to a Board

Until the beam is actually set into place, nearly everything is theoretical. The holes in the beam are supposed to line up with holes in the posts. The posts are supposed to fit onto the screws on the foundation. And everything has to account for the slope of the roof. While the builders have ways to fix problems on-site, the goal is perfection when the parts arrive.

With everything ready, the process could begin and Drew arrived with his 48,000lb crane truck. Seeing the beam moving around the site was a sight to behold and everyone was a little on edge. Its size and mass made it dangerous.

beam moving around the site

Within a few minutes, the beam was in place and I marveled at the precision. Drew could move a two-ton beam an inch at a time and place it perfectly over the posts.

Drew could move a two-ton beam

Soon it was obvious: the theoretical had made a successful jump to reality. The holes lined up perfectly and the beam was positioned just as it was designed. We all breathed a sigh of relief.

designed 1
designed 2
designed 3

Over two tons of steel now rested on posts attached to the house’s foundation and created an essential part of the structure.

house’s foundation

It was finally possible to see, for the first time, how far the roof would extend on the water side of the house.

the roof 1
the roof 2

I was fascinated by all the steps it took to make it happen. The plans, the engineering, the templates, the fabrication, the expertise. It all worked and now, our roof is not going anywhere.