1870s construction - arched rods at column 1

[BubbaJ]

Renovating an 1870s era building. The beam on the right is severely deflected, more than 4" and needs reinforcement. The roof joists are face nailed to the beam so options are limited to the bottom of the beam. I'm thinking a new steel beam to carry all the load and assume the deflected wood beam does nothing. We would need to shim to the bottom of the wood beam to get as much bearing as possible. I don't think jacking it up is an option.

Question is, what does everyone think about the arched rods at the column. Do you think they serve a structural purpose, some type of knee-brace? Architectural?

Unfortunately, there are no interior photos of the original construction.

Did I mention historic tax credits are involved? Mercifully they are putting back a gyp ceiling.

Looking forward to hearing your thoughts.

-S

 

[dik]

Some people get all the neat projects. If restoration, can you frame it using other materials? You might have to duplicate the original work. By face nailed, do you mean 'toe nailed'? Encountered one project where the joists were mortise and tennoned to provide support of the joists. Is this a possibility? If replacing with steel, can you locate the member so it is not visible? The challenge will likely be finding a manner of reinforcing the members and making the repairs 'invisible'.

Dik

 

[JAE]

I can't imagine what sort of structural purpose they would have - little if any stiffness.



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[boo1]

could they be part of a lighting arrestor system or grounding?

 

[OldBldgGuy]

I can't imagine that the curved rods are or ever were doing anything structural, they must be architectural. The roof looks a bit more complicated than simply rafters(joists) on a ridge beam. The near side also has purlins over the rafters, and a different slope apparently framing back in. Why not do something new, but elegant and fitting with the curved rods? A tie between the column you show and the next one, with a vertical at the centre, would be light, fitting, and structural. The existing ridge may be sagging but if you convert it to a compression member with half the length in bending it will probably be okay. This isn't exactly the right picture but it's what I got in 30 seconds from Google.

 

[OldBldgGuy]

Sorry, I just looked at my attachment & that's the wrong picture (I'm not sure how I uploaded that one). This one shows the principle.

 

[bowlingdanish]

This is unrelated and probably a silly question but why are they all like... randomly and incositently white? Some bloke with a powdercoat gun spraying the ceiling and it got through?

 

[BubbaJ]

@dik: I am thinking perhaps a "C" channel bolted to the near side of the beam, which is the side with the ceiling rafters attached (the roof framing runs parallel on the near side.) Then they can attach the ceiling joists back in some manner. They are going to have to accept some "visibility", it would take a 7x14 LVL to replace the existing wood beam.

@oldbldgguy: That is a very cool detail. Might be too nice for us.

@bowlingdanish: It's plaster and drywall dust from the ceiling and walls. It was hanging thick in the air after demo. "cough cough"

 

[OldBldgGuy]

The concept I showed is actually very economical if you do it right. Cable or steel rod with threaded ends or a turnbuckle is the tension member, the connections at each end are flatbar fabricated into a U & bolted through the existing beam, and in small cases like this, one vertical HSS or wood post with steel endplates supporting the centre of the existing beam. See attached for the cartoon version.