Ice Dam - Colorado

As some of you know, I am an Electrician by trade so now I turn back to you guys with more experience to help in an area i’m less familiar with… Roofing.

So I just finished my roof inspection and ventilation classes and I am reviewing notes and my past experiences… Here is an issue I have at my house.

We live in Northern Colorado (Windsor) and had hail damage when the Tornado came through some years ago. Roof got replaced all new.

Now ever since then we have had an issue with ice damming in one area of the roof. It is a split level master bedroom north side we get condensation in the room due to ice damming.

Keep in mind the house was built in 1999 we moved in in 2000 and the roof was replaced in 2008. We never before the replacement had issues.

The roofing company has come back several times to investigate and keeps telling me it’s not their concern. In order to mitigate the issue (being an electrician) I heat traced the gutter so an ice dam cannot form.

However after reading and learning from all of you and the classes I am seeing that typically ice dams are formed due to poor ventilation of the attic.

The question… what should I look for in order to identify the source of the issue based on the fact that pre-new roof I had no issues and post- new roof I have had issues every year?

Any ideas you may have would be helpful and a good learning opportunity for me…

Look for areas of insulation missing or displaced, ventilation which is now poor for various reasons(failed baffles, insulation blocking it, ridge vent clogged, etc.), vents pumping warm air into the attic or can lights recently added which are increasing heat in the area.

Condensation in the room is usually due to missing insulation, which could also be warming the roof in this area through heat loss and leading to premature melt-off and ice damming.

Is this a cathedral ceiling or does it have an accessible attic above?

It does have an attic space above. I have been all over the attic and didn’t see anything obvious. Currently I am over seas for few more months and can’t look today with new eyes. Just trying to wrap my head around what could cause the issue…

Is it coincidence that the issue happened after the new roof or is there something they could have done to create the issue while putting the roof on?

There are no ridge vents. No can lights at all on the second floor.
No one other than myself has been in the attic and only after the ice damming started.

Here’s InterNACHI’s article on Ice Dams.

I wouldn’t rule out anything yet, but I would look with a fine tooth comb at everything in the area in question, both inside and outside. Even a tree cut down could allow sunlight where it wasn’t before and heat the attic differently than before.

I appreciate the input; when I get back stateside I will definitely be going over all the venting and the attic space very closely…

more info

I would check all of your flue pipes roofers are famous in my area of knocking the pipes loose in the attic and not checking to see if they are still connected below the roof decking

If there is soffit venting, then there has to be ventilation at the top of the roof as well (such as gables, ridge vents, or box vents?). If they changed the venting (switched from box to ridge vent) you may have inadequate ventilation at the top of the roof. A problem with ridge vents is that the contractor uses the cheap roll type, which tends to crush when installed, therefor reducing the venting capacity. A solid baffle type ridge vent is best.

I am not a fan of shingles on an unventilated roof deck as indicated in Roy’s link. Despite what BSC and spray foam people push, this is not a new technique. Shingles have been installed over unventilated decks, such as board insulation with a nail-able face, for years. Doable? yes. Best practice? I don’t believe so. Besides, most wall assemblies are ventilated, why not roofs?

I see that you have received some great answers!

When you get back to the states try to come to the monthly Denver Chapter of NACHI. There is no cost and we usually have some education. Sometimes we have a presenter. Last night we talked about report writing and critiqued a couple of inspectors reports. The important thing to keep in mind is that we help each other there much like what happens on this forum (when people aren’t bashing each other on the forum :mrgreen:).

The meeting is on the second Tuesday of the month at Perkins restaurant. Colorado Blvd & I-25. I know it is about an hour from you but it will be worth your time. There is an inspector that drives down from Ft. Collins every month.

If you have any questions let me know.

Check inside your house with a hygrometer for your rel humidity levels, a lot of people bump up their humidifier to compensate for the extreme cold and dry skin. Air sealing is more important than insulation, if that moisture is reaching that cold surface, then that their is your problem my friend.

One more thing, verify the roofers installed a baffle vent to your bathroom exhaust fan if it exhausts through the roof, and make sure it is all connected and sealed. If you don’t have a bathroom fan, get one. Insulation and ventilation in your attic is important too, so make sure it is all properly installed.