One of the hottest topics in energy efficiency and building science is “how should you insulate your attic?” Why? Simply put, the attic has more impact on your efficiency and comfort than any other single part of your home!
Let’s summarize why the attic is so important:
The attic is the hottest part of the house in the summer and is cold in the winter
Hot air rises up to the attic / cold falls drops into the living space
Moisture rises and accumulates in the attic
Central heating/AC systems and ductwork are often in the attic
I was recently sent this excellent set of references on mold. The very mention of mold sends shivers up people’s spines and makes them start sniffling, worrying about adverse effects. These references help to answer your questions and learn how to deal with your mold problems.
Humidity. Moisture. Water vapor. Evaporation. Condensation. Mold. Rot.
These are all words that go together in people’s minds when the topic of humidity comes up. But what is it and why is it so important?
I’m going to try to explain this as simply as possible, so for the scientists and engineers reading – please cut me a little slack. I’m going for clarity over precision. However, if you catch the inevitable factual errors, please point them out so I can correct them.
Crawlspaces – those nasty, damp, moldy spaces under your home that you dread entering. They’re one of the least understood parts of a home and the source of countless problems. In this post, I’ll review some of the worst problems and how to avoid them.
Crawlspaces often have two big issues:
Water / moisture – leading to mold and wood rot
Cold / drafty – leading to uncomfortable conditions and wasted energy
Now that you’ve survived a storm, the water has receded and you’ve got your power back, what next? In all likelihood, you’re probably dealing with a wet rug or carpeting and dreading the idea of tearing it all up and throwing it away. But do you really need to do this? The answer is, “it depends.”
If your flood was caused by a stream or river, chances are you’ve got mounds of mud in your basement. While this silt may be great for growing crops, it’s really bad for carpets and the amount of money you’d have to spend cleaning up is probably greater than what it would cost to rip it out and buy it new after your basement has dried out. In addition, there’s a good chance that the water was polluted and maybe smelly, so you probably want to get it out of your home ASAP!
On the other hand, if the water was relatively clean, and your house doesn’t yet smell like a wet dog, you might be able to salvage the carpet. But it really depends upon the situation.
There’s nothing like a gentle Springtime rain. But Summer often brings us torrential downpours, and along with them, roof leaks, incredible moisture and mold!
A few days ago, we had record rainfalls in Eastern Pennsylvania – five inches of rain in some areas. This fortunately came after an extended dry spell, so the rivers didn’t flood this time. We got really lucky.
These heavy rains often bring high winds, fallen branches and roof damage. Sometimes, they’ll just lead to enough leaking for you to notice. Maybe there’s a discoloration on your ceiling or window jamb. Whatever the sign, please pay attention. Failure to deal with a “small” leak now can lead to thousands or tens of thousands of dollars of damage to your house later. Worse, the accompanying mold can pose a severe health/allergy risk.
When dealing with leaks, you need to take several steps in order to minimize the chance of more serious damage to your home:
In the first installment on attic insulation, I discussed why it can be dangerous to add insulation to your attic without air sealing the attic floor first. Moisture can slip through tiny cracks in the attic floor and lead to rotten roofs. Given this information, we walked through the process of finding and sealing all those insidious air leaks in your attic, some easy, some difficult. But finally, after fixing all these problems, you could lay more insulation down on your attic floor, more confident that doing so wouldn’t lead to a humid, moldy attic.
But what if there’s an easier way?
Whether you’re building a new house or retrofitting an older one, you can make life much easier on yourself by using professionally applied spray foam insulation that air seals and insulates in one shot. There are two ways of doing this, each with their own benefits and disadvantages. We’re going to review both methods. One is spraying foam on the attic floor, instead of using loose fill or batt insulation. The other is spraying foam under the roof deck. Continue reading →