stained roof sheathin/planks

[CHARLIE VAN FLEET]

guys

i know there are simular posts but asking anyway--did this 1927 home--only gable vents {roof needs replacing} and they were clogged and all new pot lights installed in kitchen and rooms--there is this stain on roof planks i'm sure condensation and mold like substance--and a strange section in photo 3--some planks have been replaced--just wondering how i should write it up-young couple first time home owners and Mom expecting--pretty sure it is poor ventilation and heat escaping from below-recommended mold contractor give it a look

thanks

cvf

[Jim Robinson]

That's certainly possible, but I usually see a much heavier concentration on the north side when it is condensation. It is also usually most noticeable above the bathroom area, and then sort of dissipates as I get farther away. I've seen some outdoor wood turn black like that in sheds and similar where I assume it was just long term heat exposure.

You are able to rule out a fire? That's a lot of black for mold in our climate.

[Jerry Peck]

You are able to rule out a fire? That's a lot of black for mold in our climate.

I'm thinking smoke from a fire also.

Another possible option may be a preservative sprayed on at time of construction? I have seen similar in crawlspace of old houses, sprayed all over with a black substance, resulting in similar look.

[CHARLIE VAN FLEET]

guys

I walked all the way to back of attic and this is east and west sides of exposure--i rubbed my hand all over it and no soot came off and a slight dust came off and i did not smell any fire related residue--what did u think of that last photo with cut board--remember this is 1927 home

thanks for the help

cvf

[Gunnar Alquist]

cvf,

I'm thinking not soot. Take a look at the gable-end. Staining lightens-up near the studs, so I wouldn't think it was caused by soot (but I am not a forensic fire specialist). I agree with your thought about ventilation, but I don't have a lot of faith in the mold guys. To the best of my knowledge, darkness does not necessarily equate to mold.

[Jerry Peck]

hat did u think of that last photo with cut board--remember this is 1927 home

One of the reasons I was thinking a fire.

Cut out the burned wood areas/pieces and replace with new.

Notice the new smaller size, lumber with the spacer on top, and even then the rafters are not even down to the old lumber size raftformat?

The new board sheathing will also be smaller in size (thinner and not as wide as the old boards.

What material was the shim made from?