Q. I recently got a “framing” inspection for carpentry. The inspector asked me to get all electrical wiring and plumbing pipes in before he would look at the way the wood framing was done. Then he rejected the work because of the way the beams and columns went into the walls. We had steel beams put in so we could remove all the inside walls and open the kitchen up to the living and dining rooms. It’s now one big open space. The carpenters cut the wall tops and bottoms so the beam and column could go in. Is there a way to fix this, and why is it so important? The inspector said the architect would need to write a letter explaining the fix.
A. Your inspector is looking out for you. He didn’t accept the work because the interior walls that were removed had an important role to play in holding your house together. Now that there are no walls running at right angles to the outside wall, the strength of the exterior walls has been reduced, enough so they can waiver in a high wind and compromise the home. In other words, the long, unbraced wall can collapse in a heavy storm.
From flying in a plane, you may have heard of wind shear. It’s caused by pulsing crosswinds that work like a giant hammer, pounding directly at the wall’s surface, like pounding a big drum face, and is referred to as positive pressure. The wall is also brushed by winds that run parallel to its surface, which causes a suction known as negative pressure. Together, the pulsing is tugging at the wall and pushing it, causing opposite reactions that, if the wall isn’t properly braced, can make it come apart and wrench away from the rest of the building.
By cutting the continuous top and bottom wall “plates” that run around the whole structure, the wall is no longer attached at these points. That’s one reason why windows and doors receive extra support around the openings. The “weakest links” are the places where the connection has been severed or removed altogether, as when steel beams and columns are inserted into the wall and the wood has been cut away.
Some argue that the steel beam and column actually brace the structure, but only if they are attached to the surrounding dissimilar wood. In most cases, when an inspection is done, the lack of understanding of the wind shear process is revealed, and hopefully it is discovered before a disaster and not after. This can be repaired by making the wood walls connect again, using steel sheets, steel strapping or plywood that bridges the wall studs on either side of the steel column and beam. The plywood will stick out if the wall is only as thin as the column, but with large wall studs, the plywood can be recessed to be even with the rest of the carpentry.
© 2021 Monte Leeper. Readers are encouraged to send questions to email@example.com, with “Herald question” in the subject line, or to Herald Homes, 2 Endo Blvd., Garden City, NY 11530, Attn: Monte Leeper, architect.