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posted: 6/15/2014 12:01 AM

Ventilating bathroom fans through roof is far from ideal

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Q. We read your information in a recent Sunday column about not venting bathroom fans through the roof. We live in a two-story home with a hipped roof. We have soffits all around the house. Our first-floor powder room and second- story bathrooms all vent into the attic. We had an HVAC contractor out to give us an estimate to properly vent the fans. He wants to vent through the roof because we do not have gable ends on our house. He would use a vent with backdraft for the job. We live in the Midwest. What do you recommend?

A. The problem about venting through a roof in a cold climate is not only the backdraft, but the condensation running back down into the fan housing, causing it to rust, and wetting surrounding insulation and ceiling finish.

Although it is not desirable, if your soffits are not vented, this is your better option as long as the vents are capped with hoodlike jacks to direct the outflow downward.

Q. I have a few more questions about ridge vent ventilation and gutter guards. I have attached pictures.

I had a roof installed last year. I knew nothing about ridge vents, and they installed a Cor-A-Vent Rolled Ridge. I have come to read in your columns that an externally baffled ridge (EBR) is the way to go. I haven't noticed any issues with the rolled ridge. I have vents on my front porch ceiling, soffit and the house front. I only have vents on the front of the house, as there is no soffit on the back. I have two gable vents. My back porch has a ridge vent as well. So here are the questions:

Should I seal off the two gable vents in the regular roof area as well as the gable vent in the back porch? Should I also seal the small opening between the back porch and the regular roof gable? Is it necessary to replace the rolled ridge with the EBR? Is replacement as easy as removing the rolled ridge and installing the EBR? Do they fit in the same opening? What indication would there be that there was an issue with the rolled ridge?

Now to the gutter guards. I read a column of yours several years ago recommending Flo-Free Leaf Guards by DCI Products. I sent for a sample and it looks very interesting. I'm pretty sure I read a follow-up column indicating you were no longer recommending that product. Why is that? I currently have an inexpensive plastic guard that snaps in place on the gutter. Not sure if it is the best product or how long it will last. Do you have any other recommendations?

A. Your situation is far too complex for me to give you intelligent answers. It would require a site inspection to investigate the entire picture on site. You would be best served by having a certified energy audit performed.

Externally baffled ridge vents are the only ones you can depend on under any unusual weather conditions such as strong winds with heavy rains or snow. That does not mean you should go to the expense of changing what you have; it is simply unfortunate that your roofer is not more knowledgeable.

Replacement would be easy, if you decide to have it done; if the proper slot was cut on each side of the ridge, it is a case of a simple exchange.

If the ridge vent that was installed has ingested snow or rain, you should see wet insulation or snow accumulation on it in an accessible attic.

I installed DCI Flo-Free Leaf Guards on our gutters several years ago. I later found out that tree debris -- twigs, seeds, needles, etc. -- collected in the depression between the drip edge and the top of the guard. It made a mess.

I discussed that with DCI and was told that, yes, it can happen and that they sell a metal piece to close that depression -- at a very high per-foot price. Before that conversation, I already had my favorite contractor make me similar pieces and install them at a much lesser cost than just buying the metal from DCI. It has helped, but this is another case of gutter guards causing other problems while attempting to solve one.

Nevertheless, at this point, I haven't found anything better. I have investigated and used several other types of gutter guards over the years and have been disappointed with all of them, which is why I prefer to trust larger commercial gutters and downspouts, or the RainHandler (

Q. When you answered my question about roof leakage inside the house, although I had my roof replaced recently, you really got my attention when you said, "There is something wrong in this picture." I called the roofer and he came to see the problem, and told me he used 8-inch drip edge and two rows of ice and water shield (IWS). He could not understand what caused the problem.

The next day, I got the ladder out and peeled up the shingle edge. Observation revealed the drip edge is only the standard 3-inch length, and there was no IWS -- over my attached garage or on the attached shed roof. I now understand what caused the water problem.

I called the roofers and was told they don't put IWS over an unheated area. The garage shares the main roof and is heated only by two of its walls that are heated rooms, so there is enough conductive heat so the garage seldom gets below freezing. Obviously, this should have IWS because the icicles were in my attic and dripping from the soffit vents. Prior to the roof installation I asked for two rows of IWS all around the house.

I am now waiting for the roofer to come to my house to see what corrective options are available. Do you have any suggestions or comments? To say the least, this has been a frustrating experience. When I had the roof quoted, I went with the most expensive to assure a quality job.

Thanks for the tip on the soffit vents; it's now on my summer project list. I assume I'll also need to close the three existing gable vents. Can you recommend a manufacturer of a continuous soffit vent or a particular style/model? On a side note, after the new ShingleVent II ridge vents were installed, I noticed a lot of bees in my attic and also about 30 small bees' nests in the unfinished attic peak, which I removed. The roofer stated he always removes the filtering material as it often becomes clogged. Do you have a suggestion on how to stop the bee invasion?

A. It looks as if the roofer was not very honest with you. Do you think you can trust him to make the proper corrections?

To install an ice and water protective membrane as you had specified, and presumably you paid for, will require removing shingles down to bare sheathing. But first, the drip edge must be installed, as it needs to be covered with the membrane at the eaves.

Before you install soffit vents, make sure there is an unobstructed space of approximately two inches between the roof sheathing and the top of the insulation to allow a free airflow between soffit and ridge vents. Otherwise, it is pointless. Then seal off the gable vents.

Off-the-shelf soffit vent strips are sold in building supply houses.

The roofer should not have removed the filtering material from ShingleVent II; one of its purposes is to prevent insects from entering the attic.

The roofer should replace the filtering material, which he may not be able to purchase separately. Don't allow him to put any other filtering material, as it could affect the functioning of the ridge vent. If need be, it's his responsibility to replace the entire ridge vent.

It always amazes me to learn of the number of times when contractors, or their workers, make such poor decisions, and defeat the purpose of the manufacturers' carefully designed products, or do not read the instructions provided with the products.

Q. I have a 40-year-old home in western Pennsylvania with gable vents and no soffit vents. I recently had my roof replaced, and by mistake they installed ridge vents, which I did not want. They said they could remove the ridge vents. Would it be better doing that, or just block off the gables? The only exhaust has been a small roof fan and the gables for 40 years, so I'm OK with that. Any suggestions?

A. Since you have no soffit vents, the ridge vents are not very effective, but there is no reason to remove them. They represent another exhaust for hot air in the summer.

Your attic ventilation system is not ideal, but if it has worked for you, there is no need to change it.

Q. We like to travel at variable times in the winter, and we have had bad experiences with trusting the furnace. We are now thinking of using two oil-filled, portable, thermostatically controlled radiators set just below our furnace setting as backups.

Our home is 1,300 square feet, well-insulated with a full basement. Do you have any better suggestions?

A. I do not quite understand what the radiators would accomplish.

If you have neighbors you trust, it would be better and safer to set up a warning system, which would notify them if the temperature drops below a set level. You can buy one of several online. Here are several to check out:;;, and enter low temp alarms in the search box;;;

Some have telephone connections that call one or more numbers when the temperature drops below the setting.

• Henri de Marne was a remodeling contractor in Washington, D.C., for many years, and is now a consultant. Write to him in care of the Daily Herald, P.O. Box 280, Arlington Heights, IL 60006, or via email at

© 2014, United Feature Syndicate Inc.

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