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Sometimes in older homes, or homes where bathroom or kitchen fan placement isn’t well-designed, a backdraft can occur that causes cold or otherwise outside air to come into the house.

We have a client whose master bath fan is on a corner of the house which tends to get a lot of wind.  This means that during those times when the wind is hitting that side of the house, outside air is making its way in through an old fan exhaust duct back into their bathroom.  Most of the time this causes the damper (which obviously isn’t sealing properly) to flap against the edges, creating a rather constant and annoying sound.  This becomes worse in the winter months as the air drops below freezing, causing the bathroom to become very cold – as well as wasting energy for the home’s heat system to try to recover the heat loss.  Needless to say, between the sound and the cold, Mrs. Client is definitely ready for a fix.

There are a couple ways to fix this issue, ranging from the cheaper to more pricey.  The costlier end of things is such because of the overall worth of the replacement/installation of something like an ERV (Energy Recovery Ventilator)/HRV (Heat Recovery Ventilator).  The difference between the two is that the ERV transfers temperature and humidity, whereas the HRV only transfers temperature.  Your choice between the two will primarily depend on climate – where cold climates will typically have little moisture issues and hot climates typically have major humidity issues.  There are a variety of brands of ERVs/HRVs on the market, each of which tending to have their own twist on the product/installation.  The jist, however, is that in a residential installation the ERV/HRV typically connects to the furnace return air.  This means that the air being vented out from rooms, before being exhausted elsewhere outside, runs through a chamber next to (but not mixed with) fresh intake air.  This chamber itself is called the ERV/HRV.  The proximity allows them to share temperature (hot intake + cooler exhaust = decreased temp of intake and vice versa), tempering the air before being sent to the return air plenum to be adjusted to the final temperature desired for within the house.  This natural tempering reduces the strain, and therefore energy use, required to create the needed air temperature.  Point-source exhausts are still typically required for things such as bathrooms, laundry, etc – but it is possible  with certain systems to exhaust this air through the same method as mentioned above so that the heat from say, a shower, is not lost before exhausted.



This system is not designed to be used as a stand-alone, but as an additive to air-conditioner/furnace.  It is also important to note that the system is not meant to act as a dehumidifier during hot humid months.  A stand-alone dehumidifier will do more for moisture issues in that situation than either an ERV or HRV, though the ERV will do better than the HRV.  In fact, we believe the ERV will typically do better in about every scenario compared to the HRV.

Moving on…

Another option would be to re-route the exhaust exit, making it easier to ensure that the air is actually exhausting and harder for air to come back in.  This is less invasive than the previous option, but will still require some renovation work.  The other, cheaper option, is to merely replace the damper within the ductwork.  We found a damper through Fantech which we are planning to install in the previously mentioned clients’ home.  It works on a spring-load property so that when air pushes from within the home, the damper opens, but then springs back shut after the air pressure is gone.  Because of the spring-style design, it cannot buckle open the opposite direction, cutting off the ability for exterior air to make its way into the home.



We hope this has provided you with some insight into the world of backdrafts.  We promise that your wife will be happy with the lack of noise and your wallet will be happy with the lack of energy loss.

Category : Uncategorized | Blog

Or: “Why we still believe in Mythic”.

We recently came under some scrutiny for a previous post about paint.  As we are a working firm of a few, dedicated (read: very busy), hard-working people – we like to get information out to our customers and others who might come across our blog in the most concise way possible.  This means that we don’t necessarily delve into the details, or have time to research them.  Now it’s time to lay out what we’ve found in the past few days:

1. Everyone has an interest.  Most people who want to change your mind about something or tell you about a product have an interest in that product doing well.  Like, say, they SELL that product.  When you have an interest you tend to only pay attention to certain facts, or skew them – because how that product does affects your pocketbook.  Now, I say most with italics because, while we love Mythic, we are not in that category.  We get nothing from praising their product, other than the fact that our projects are healthy (for both the people who make them and the people who use them) and require much less touch-ups.  And maybe if we praise them enough, people will catch on to their awesomeness and consider trying them out as well for their next project.

2. MSDS (material safety data sheets), while frequently used as the “bible” of the building world, are actually no such thing – nor were they ever meant to be.  It came about for the manufacturers and people who work with said product, so that they knew how to safely handle it and what they were dealing with.  It was never meant to be an ingredient list, or recipe.  No, it does not tell you what is in the “proprietary” blend or piece of something that might go into every product a company makes…but then you’re getting back to an ingredient list.  And the ingredients of the proprietary blend would be listed if they were deemed hazardous.

3. No company in their right mind is going to give you an ingredient list.  No, that doesn’t mean they’re hiding something.  It just means that, unfortunately, in the world of today – you can’t trust a competitor to get ahold of that and steal your product, merely labeling it differently.  Where the MSDS leaves off is where other stringencies come into play.  Like California prop 65 – where they have to disclose any harmful ingredient known to cause medical issues.  Or where third-party verification is needed.  So you have an un-biased party testing your product to verify that what you’re saying is legitimate.  Guess what…Mythic does that.  They were even taken to court by Valspar in relation to their statements of No VOC, No Carcinogens.  Guess what. They won.

The important factor here is that you, as a consumer, do your research.  Yes, sometimes it can  be daunting, but wouldn’t you rather know the product you’re using is quality and healthy for you?  Too frequently we, as consumers, today take things at face value.  We see that it says “no VOC” on the can, and don’t bother to worry about the colorants or other carcinogens.  We go to the store without thinking about durability and wind up with a paint that reqires 3+ coats, doesn’t cover evenly, and more frequent touch-ups.  We look at a product that has a label that makes it look like it’s green, or like it’s been tested and passed something, when really it’s just something the company’s marketing department made up (this variety of testing/certifications is a whole different elephant in itself).  I know you’re out of school, but the learning doesn’t stop.

Category : Indoor Air Quality | Product Review | Uncategorized | Blog