Shop roof...one more time

[JSUPreston]

I know I've driven y'all nuts about my shop roof, but since there's no room in the budget for a new shop any time soon, I thought I'd ask one more time if maybe something could be done with my roof.

I asked a few years ago, and at the time I was thinking of the possibility of sistering the existing rafters with wood i-beams or replacing the girder that runs mid span. Here's what I have.

Running east-west, I have 2x6x14' rafters (estimated length) with a lap joint mid way. Rafters are roughly 2' OC. Running north-south, I have 4 2x8x10' girders. The girders are paired up and meet dead center of the shop. I have notched 4x4 posts that directly underneath where the girders meet. The decking is a mix of 1x6 and 3/4" ply. The roofing material is rolled membrane. The building is 20x20 concrete block and is completely freestanding.

Here's the problem. Last time I asked, LarryG was kind enough to get some calculations done and determined that a 14" deep LVL would traverse the span where the 2x8 girders are now and allow me to get rid of the center posts. However, at my height of 5'8", the girder and my forehead would become intimately acquainted every time I went into the shop.

Since then, I've been thinking of fish/flitch plates where the 2x8's meet. Recently, I've thought about the possibility of attaching 2x2x.25 angle iron to the side/bottom of the 2x8's and having the angle iron span the entire shop.

I've attached pics this time to maybe help a little. Please excuse their crudeness. Taken with an iPhone and resized in MS Paint.

West wall:


Center post (Only 2 of the notched 4x4's are load bearing):


Under the sistered 2x8 girder looking at center post:


Lap joint of the rafters and back side of girder:


East wall. Bottom of rafters are a little over 6' from the floor:

[chopnhack]

I remember some of the previous post. I would suggest you do the minimum to get your roof in good working order. I do see where some of the leaks have stained the wood. I wouldn't try and get rid of the central support, it will probably entail more money than its worth.

Work with what you have. Get some jack screws and "straighten out the lumber that has sagged and then sister up same size piece and bolt together. Use heavy square washers to distribute the load and use a w pattern. If you want to nail use 10d and also use a w pattern. On the block wall I would chisel out some of the rim joist to create a pocket where you can slide in the new lumber. I would put another short section below the rim joist, perhaps 4-6' and bolt that to the wall in several places to aid the old rim joist. This would be another good application for the screw jack or some clamps - you do want the new lumber in tight contact before you fasten them.

After you have the structural items shored up, do your tear off and any removal of damaged boards followed by reroof.

Sorry its not what you wanted to do, but why waste money at this point. It certainly will not be a pole barn without significant work and money, but at least it should be water tight and workable for a time.

[JSUPreston]

The water stains are from before the roof was replaced. I had to patch a couple of minor leaks from limbs hitting the membrane roof right over a gap in the decking, but otherwise, the roof has been water tight since it was replaced.

I'll have to think about what you've said...too tired to think about it tonight.