Expert: Daniel Humphrey - 8/15/2010

Question
QUESTION: I recently purchase this house.  It has a hip roof that cantilevers.  The red beam in the picture is rotted.  I started to cut some of the rot out as you can see in the picture.  But before I get started I had some questions.  Is that red beam supporting the roof?  It is a 4” wide x13” tall piece of wood.   I am not sure how far back it goes.   I wanted to know if you have seen such a configuration.  Do you know how far back that red beam goes?  What are the options in fixing it that you would recommend.   I would have to pull out the trim and T1-11 to see how far back the beam extends.  I hope it does not extend into the house.  Plus I am not sure where to buy a 4” x 13” piece of wood.  Are there other options?  I thought about trying put 2x12 on each side, but that might look odd.   I also thought about just cutting out the rotted part, but that would take me right up to the roof rafter that it supports.  Also it seems like it is rotted at the top under the roof rafter, so I would have to cut some of that out and try and glue some piece of wood to replace the wood I cut out.  Any suggestion are appreciated.

ANSWER: Dear Robert,

Yes, I have seen that kind of roof, with the lookouts projecting beyond the roof, and they all rot.

The proper fix for that would be to remove all the rotted wood, scarf on new wood to whatever remains solid,  and rebuild the eaves. But a more simple repair would probably be fairly easy and last many more years.

The red beam may actually be supporting the roof inside. Or it may be a cosmetic lookout. In either case, you should cut all those lookouts back and protect them with fascia. The danger is that the water they suck in will start to rot the rafters and wall. They don't support much, if anything, of the eaves.

For the ones that are really rotten, you can remove the rotted parts and epoxy pretty wood around them, essentially creating box beams. Keep all the new wood under the protection of the roof and fascia.

Daniel



---------- FOLLOW-UP ----------

QUESTION: One of the factors effecting which way to go, is how much support that Red Beam Lookout provides for the Barge Rafter.  If it just provides minimum support I would just cut the Red Beam back to the Barge Rafter and putty any remaining rotted wood (basically the easy method you mentioned).  I thought there might be several 2x4 turned flat lookouts that support the Barge Rafter and the Red Beam Lookout might just provide minimum support at the end.  But in addition to the Barge Rafter there is another Roof Rafter on the outside.  I was not sure if under that condition 2x4 lookouts could support both roof rafters, the roof sheathing and the roofing materials.  Normally what I have seen is the 2/4 lookouts nailed to the Common Rafter then laid over the end rafter (which is notched out for the 2/4s) and that supports the Barge Rafter 2 foot out.  I can see where that would provide enough support.   I just was not sure about 2x4 lookouts supporting 2 rafters on the outside.  What have you seen and your thoughts on what is supporting those two outside rafters.  Because I would prefer to go the easy way you mentioned and not tear everything out.

Answer
Robert,

The barge rafter on an eave as small as yours is supported mainly by the stiffness of the roof sheathing. I think of it more as a straightener and stiffener than a weight support. The end wall (gable end truss) of the house carries almost all of  the load of the roof at the gable.

You also have some wall returns holding that rafter set closest to the end wall.

The rotten portion of the red beams probably aren't contributing much as it is. For the most part, the lookouts of the red beams are cosmetic. Cutting back and patching will restore their function, and you may not need to cut back very much.

Daniel