Small Void and Soft Spot Around Bathroom Skylight

[vipercwf]

I always check my roof every year this year I found soft spot around my bathroom skylight. It’s not real big but a small part of it (maybe 4x4) feels completely void of under decking so has to be totally rotted away in that part. Feel confident leak was from minor hole in the membrane I extended dicor from skylight seal over to it. Just debating if I should leave it be with it being small like that or should I actually cut into it and replace that small area of decking. I was planning on recoating my roof with an elastomeric rubber roof coating to extended its life a little longer. I definitely don’t have the money for anything major like whole new roof etc. Because it’s nearly halfway on camper and on awning side it would make for a significantly bigger job removing side cap all the way down and rolling that much membrane back to get to it. I’m just not sure if it’s worth doing either way and would like some thoughts from others on what you feel you would do - part of me thinks it won’t be a big deal now that leak is fixed and it’s rather small area unless that rot would just continue to spread? For some reference the blue circle is the void soft spot. The yellow circle is where the leak was and the blue line does have some softness but not void. I’d really just like to hear some other voices on what to do. Any thoughts are appreciated.

 

[Kirk]

small area unless that rot would just continue to spread?

Dry rot can and often does spread even without additional moisture. It looks to me as though it is time to remove and replace all of the old caulking as the discoloration makes me suspect that it is in poor condition and may well have been the cause of the leak. If it were mine, I would clean up that old caulking and remove the skylight to see what the decking around it looks like. Most likely the membrane will easily lift in the area where the problem is. If you do repair it and the area is small, I would just cut the membrane where you need to work and then replaces it and then add a patch. Patching kits are available from Amazon and most RV supply stores.

 

[Rene T]

I would remove all the globs of caulking and apply some eternabond tape and maybe even some Dicor caulk after that. Other than that , leave it alone . Also use the tape over the hole where water got in.
Oops, Kirk beat me

 

[TheBar]

I had roof damage 6 years ago from carpenter ants. My repair is still sound so it worked. See how I repaired it here : Roof Repair

 

[TheBar]

You may not need to replace any wood if it is just soft and has not rotted away. Minwax liquid wood hardener and/or putty will work for small areas like you have. You will find it turns the rotted wood into pretty hard plastic that will not rot again.

There is no need to replace the membrane. Just cut it carefully as needed and afterwards glue it back down with contact cement. Eternabond over the cut area and it should last 20+ years.

 

[vipercwf]

You may not need to replace any wood if it is just soft and has not rotted away. Minwax liquid wood hardener and/or putty will work for small areas like you have. You will find it turns the rotted wood into pretty hard plastic that will not rot again.

There is no need to replace the membrane. Just cut it carefully as needed and afterwards glue it back down with contact cement. Eternabond over the cut area and it should last 20+ years.

Thank you for your help and suggestions. I’ve been looking into what to use for glue on membrane back down to new plywood but seem to only find the large pint of acrylic bonding adhesive that’s expensive and won’t need anywhere that much. Are you saying the standard contact cement stuff from hardwhere store will work? I know you gotta be careful on what products work with the epdm membrane. Thanks again

 

[TheBar]

Thank you for your help and suggestions. I’ve been looking into what to use for glue on membrane back down to new plywood but seem to only find the large pint of acrylic bonding adhesive that’s expensive and won’t need anywhere that much. Are you saying the standard contact cement stuff from hardwhere store will work? I know you gotta be careful on what products work with the epdm membrane. Thanks again

Weldwood brand contact cement was recommended by others and was what I used on my EPDM. Still holding after 6 years. Its on the shelf at Walmart or Lowes. $16/pint.

 

[vipercwf]

Weldwood brand contact cement was recommended by others and was what I used on my EPDM. Still holding after 6 years. Its on the shelf at Walmart or Lowes. $16/pint.

Perfect thanks again

 

[PancakeBill]

GitRot is designed to penetrate the pores of the wood, and then solidify. Used in wood boat repair for many years. Good option. Then do as others mentioned with membrane.

 

[RV_Lee122]

Inspect fully from the underside of the skylight as well, the European flip open ones will leak if the clamp screws get loose and dont hold the gasket tight enough. Regardless how well the caulking is. That said, remove all caulking, clean the whole area with mineral spirits and then apply all new caulking. I wouldn't worry about the soft spot.

 

[vipercwf]

Thanks for the input. My only concern is the one section is completely void of under decking roughly 4x4 directly to left of skylight. The other stuff is just soft. There is a section along edge by gutter that got pretty soft from it too so I’ve gone back and forth on whether to cut into it and replace the decking in that area

Inspect fully from the underside of the skylight as well, the European flip open ones will leak if the clamp screws get loose and dont hold the gasket tight enough. Regardless how well the caulking is. That said, remove all caulking, clean the whole area with mineral spirits and then apply all new caulking. I wouldn't worry about the soft spot.

 

[Gary RV_Wizard]

If it is completely void underneath as you describe, you should expose it and repair. That's far beyond just a soft spot.

 

[Kirk]

Gary is correct, in my opinion. By 4X4, do you mean 4 inches by 4 inches, or 4 feet by 4 feet? If the latter, you have a pretty major problem.

 

[TheBar]

According to your pictures it looks like a small area. But be prepared for the repair to be way larger than you imagine. Damage may extend for feet not inches.

 

[vipercwf]

Gary is correct, in my opinion. By 4X4, do you mean 4 inches by 4 inches, or 4 feet by 4 feet? If the latter, you have a pretty major problem.

4 inches rest is soft

 

[Kirk]

The soft areas will probably get worse and larger if left as they are. Even with no more leaking, wood rot can and often does continue to expand.

 

[vipercwf]

You may not need to replace any wood if it is just soft and has not rotted away. Minwax liquid wood hardener and/or putty will work for small areas like you have. You will find it turns the rotted wood into pretty hard plastic that will not rot again.

There is no need to replace the membrane. Just cut it carefully as needed and afterwards glue it back down with contact cement. Eternabond over the cut area and it should last 20+ years.

Can I ask did you ever put sealant around edges of the tape or has tape itself held up all by itself now for years? I have read some put sealant around the edges of the tape curious what worked for you. I also live in northern climate so winters get harsh.