Monthly Archives: August 2017

Attic Ventilation and Sizing

attic ventilation

Fair warning: I am not an engineer. I’m not a scientist, either. I do make informal hypotheses and then use observational results to determine their merits, but using the scientific method does not make an expert. The truth is most contractors, builders, and even architects aren’t either of these things either. In fact, the whole idea of “building science” is a relatively new one, which is interesting, considering that humankind has been creating non-cave places to live for thousands of years.

I use this as a preface because the home building industry makes an awful lot of its decisions based on what we’ve done before. Whether it’s a green behind the ears tradesman learning their craft from a veteran or one contractor picking up tips from another, this industry is based on handed down learning of what works and what doesn’t, with official code books issued periodically to provide continuous guidance on how homes should be built. While I’m not about to get into how codes are changed here, just know this: neither the codes themselves nor the jurisdictions who decide how and what codes get used (adopted, in the parlance) are done from a purely scientific standpoint.

With all of this in mind, it should be little surprise that attic ventilation is a thing we do because we’ve always done it. And, even more maddening, is that the seemingly scientific way of determining how much attic ventilation a building needs was just made up back in the 1940s. So, as much as I’d love to post that using a ratio of 1:300, with 1 square foot of ventilation needed for every 300 square feet of attic area, with the ventilation balanced between the top (ridge) and the bottom (soffits or eaves) is the best solution to attic ventilation, I can’t say that it’s a 100% data driven fact.

Yet, it works. Because of course it does. Funny, no?

Really, it works because;

  1. attic ventilation, while important to do correctly, doesn’t cause catastrophic failure if

       done incorrectly

2. the original ratio, whatever its origins, was most likely based on observational data

     that correlated with homes that worked right.

I will note that one of the most well-known and trustworthy building science professionals, Joe Lstiburek, does recommend using a 60/40 split for the bottom and top attic ventilation areas, with slightly more air coming in from the bottom of the space to slightly pressurize the space. This makes good sense, as it ensures that the attic won’t be “sucking” conditioned air from the living space.

For practical purposes, we put this together 12 years ago. Note that the 1:300 ratio isn’t on here but, instead, there’s a multiplier.attic ventilation

The .24 multiplier follows the 1:300 guideline but we’ve found that a simple multiplication factor is the easiest way to do the math. And, after 12 years, it’s probably time to update this with the 60/40 information as well. Otherwise, it all still works!

Hopefully, this helps explain attic ventilation sizing some. As always, there’s more to the story, especially in how the practical aspects work, but we get to that another time.

—Jeff

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How Insulation May Help Sell Your Home to Millennials

Unless you’re already in your ‘forever home’, you’ll probably be looking at putting your current home on the market. And if you’re reading this, you probably know insulation is important for energy efficiency, lower bills, and improved comfort.  insulation may also be important to selling your home to the largest group of home buyers out there — millennials.

Insulation and Selling Home

Millennials: A New Kind of Buyer

While each home buyer is going to have their own mental checklist when it comes to choosing a house, millennials tend to all have one thing in common — they want a house with proper energy efficiency. In fact, according to a recent article by Bankrate, “energy efficiency” is one of the 11 Must-Haves to Sell to Millennial Buyers.

These Buyers Want to Protect the Environment

Their belief that they need to be more “green” is one of the main reasons why energy efficiency is important to millennials. They tend to have strong, specific values and preservation of the environment is more important than material things, power, or money.

 

Morley Winograd, an author and researcher of millennials, believes millennials are the most environmentally conscious generation in the U.S., stating, “They will be interested in anything that reduces a home’s footprint on the environment, especially if it is measurable and works automatically.”

 

As a home seller, it is now your job to show millennials that purchasing your home is going to align with their values. Newer insulation means the A/C and furnace don’t have to work as hard — saving energy in the long run.

These Buyers Are Conscious of What They Are Spending

While millennial home buyers consider their environmental footprint, they are also cautious of where their money is going. Energy costs are rising, and millennials want to do what they can to avoid having to pay increased costs.

 

Again, this is where insulation can help attract buyers. Rooms will stay cooler in the summer and warmer in the winter. Who doesn’t want that?

 

Keep in mind, it’s better to already have upgrades such as new insulation already installed in the home when it comes time to sell. Otherwise, buyers will consider the amount that this is going to add to the price when they have to make these updates on their own.

Take the Next Step

Knowing your audience of potential home buyers is the first step in selling your home. Now, it’s time for the next step. Make those home improvements that are going to nudge buyers into believing your home is the one for them. Re-insulating your home is a step worth taking, and all it takes is a call to NorthStar. We look forward to hearing from you!