Should I Insulate My Floor? Sacramento’s Homeowners’ Query

“Didn’t you guys just talk about insulation?” you might ask. And we did — but attic insulation, specifically. But what about the floor, should you be insulating that? And what kind of insulation works best for your home? Is there a timeline for when you should reinsulate your home? These are three very common questions that we hear when working in homes in the Sacramento Valley, and we’re glad that homeowners are asking them. Insulation is a vital part to keeping your home running efficiently and to save on your utility bills, and understanding the answers to these questions will only help you save more energy and money.

Should I Insulate My Floor?

We get asked this question at least once a week, most recently by a homeowner in Vacaville who just completed (and rebated) an attic insulation job. We love to hear this question because it shows that the homeowner is interested in the upkeep of their home and already thinking through possible scenarios by themselves.

The answer is no, usually, but it can depend on the situation. Here’s why: you’ll remember from a recent post that we discussed how hot air rises and cool air descends and how this affects your attic insulation. Heat tends to move horizontally at an even rate of speed or up at a higher rate of speed, but it doesn’t move down. Why is that important? Because all that insulation does is stop heat from passing through. So insulating a floor would be a great idea, except heat doesn’t actually move through the floor.

However, there are a few exceptions: homes built on piers or otherwise elevated without an enclosed foundation might benefit from insulation, if only to eliminate drafts. But for most people, insulating your floor will have a minimal effect compared to the cost, which is why we don’t normally suggest it.

Which Insulation Is Best?

This is another question we get asked a lot, and it’s a little trickier to answer as it depends on the situation. There are three kinds of insulation we see on a regular basis: loose insulation (common in old houses), fiberglass batting insulation, and blown foam insulation. Let’s look at each category and go over the plusses and minuses.

Loose Insulation

Loose insulation made of cellulose or mineral vermiculite is pretty old technology by today’s standards — you’ll almost never see anybody use this insulation unless they’re re-using insulation that was already in a wall. It’s the least effective kind of insulation, which is why it was mostly replaced in the 20th century. We still see it in Oldtown, Placerville, and a few other places with older homes. If you have this in your home, it’s a good idea to consider replacing it as it’s not the most efficient choice anymore.

Fiberglass Batting

Fiberglass batting is the most common insulation in this country and around the world. It’s been used since the mid-20th century and is probably what you have in your home. Batting is cheap, easy to work with, quick to install, a good insulator, and reasonably waterproof. Fiberglass batting will meet most homeowners’ needs for insulation in walls and attics.

Foam Insulation

Foam insulation is a newer technology, and it’s growing in popularity. You spray this stuff into and over surfaces that you want to insulate and it does a great job, setting up and good-to-go in a day or so. Foam is a great insulator and it’s pretty quick if you have a good crew doing the work. It’s also pretty expensive, especially compared to fiberglass batting, and not easy to work with. If you have the money and want the best stuff around, foam insulation will not let you down.

Should I Reinsulate My Home?

This last question was recently posed to us by someone buying a home in Yolo. In most cases, you wouldn’t — fiberglass batting has a 100-year lifespan or more sp we typically say to insulate the attic and call it a day. But in this case, and a few others over the years, the answer was more involved. This client’s house was actually built in 1920, and that meant there wasn’t any batting in it. Instead, loose-fill mineral vermiculite insulation was the substance of choice, and it worked great at the time.

Now, however, our client was worried. The home required repair and remodeling, and a fair bit of the insulation was already out of the walls. Should he replace it? Would it be better just to re-pack? Was it safe to do at all?

Vermiculite contains asbestos, so we recommended having a contractor handle it no matter what he did. Vermiculite can also lose its effectiveness over time, especially if it becomes damp. As a result, we recommended the client have the insulation professionally removed. He then had several options: replace the insulation with another loose-fill insulation (like wood fill) or use spray insulation. He opted for spray.

Insulation isn’t an easy topic, and even relatively straightforward questions like these can have complicated answers. For more information on insulating your house, get in touch with us for the best answers and the family treatment.