Wet insulation and roof

[haivi]

Hello every one,

Just before Christmas, we had water dripping down the second floor light fixture. It stops after a few hours. I looked up the attic and saw that water was dripping down from the roof; it looked like humid concentration. So the next day, I hired a roofer to replace the roof vent. My house was built by Mattamy in 2009 and they were using a flat vent that might get blocked when there is a lot of snow. We replaced that we a Maximum Ventilator that rises up above the roof, the one the Mattamy now uses in newer home.

With the melt within the last few days, we no longer see water dripping down on the second floor. I just opened up the attic and looked around. For the most part the roof looks dry. However, the insulation on one side of my attic opening is wet, but the bottom is not (there is a plastic layer at the bottom). As well, part of my roof is wet (attached picture).

I am wondering if the the wet roof might indicate a roof leak. Also, do i need to replace the wet insulation? I am not sure if it was wet from the concentration before XMas, or if it is something new. Should I replace right a way or wait and see if it will dry up? My last question is if I would like to crawl into the attic, do I need to stay on top of the beams or any place would be fine? Would the ceiling dry wall holds up my weight (around 65 Kg)?

Thanks very much for your help,

[jeffjc]

can't answer your other questions but stay on the beams unless you want to fall through.

[xdarrylx]

Absolutely on the beams/trusses/joists. Anything else and you'll have a new skylight in your ceiling!

[Dellwoodking]

First impressions to me look like a pretty good roof leak!! I'd get a roofer in asap.

[good2know]

Another possibility is that you have an exhaust vent in your soffit that is not connected to outside. The moisture pattern and alignment with the plastic soffit vent makes me wonder.

Is there a bathroom or laundry room under the wet spot? Run the shower a couple minutes then turn on the fan. If its cold you should see the condensation. Look outside and in the attic.

[haivi]

Thanks everyone. Good2know, there is a bathroom vent close to that spot, but I am not sure if it is underneath. I will try what you suggested and see if there is vapour going up the roof.

Regarding the insulation foam, does anyone know if it is cellulose or fiberglass. It looks more like cellulose to me. The reason I asked is because cellulose is supposed to be resistant to mold, so I might not need to replace the wet insulation and just let it dry out.

Thanks,

[good2know]

Originally Posted by haivi

Thanks everyone. Good2know, there is a bathroom vent close to that spot, but I am not sure if it is underneath. I will try what you suggested and see if there is vapour going up the roof.
Thanks,

This may be because the pipe is not connected to soffit vent and the pipe is just laying ther. So it would be close. Hope you find rthe problem.

[Halton Home Inspector]

Sometimes when inadequate insulation is provided in the attic ( which in many Mattamy homes was a chronic problem ) then cold attic air in the attic can condense on the surface of the insulation making the top surface of the insulation wet. This is especially prevalent where 2nd floor fans and ceiling lights are installed.

In your attic hatch area there should be an "insulation certificate" showing how much insulation you should have. 2009 was near the end of the R32 days as R40 became the next requirement and now the new standard is R50 for home where permits are pulled after 2013.

Moisture in attics can also be because fan exhaust vents are not sealed properly or because of inadequate roof and soffit ventilation.

Duraflo has an excellent roof vent calculator on their website. Most homes use roof vents that are 50 square inches. To do the calculation you will need to measure the roof line of the home including soffits.

Often the holes cut for roof vents are too small and you end up with a 50 square inch vent installed over a 30 square inch hole.