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Vapor barrier and thermal insulation in crawl space of a home

Vapor Barriers, Thermal Insulation, or Both?

Is there any tangible benefit to stacking insulation with a vapor barrier, or should you opt for one or the other?

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Waterproofing your home isn’t meant to be difficult. That’s why professional contractors try to offer homeowners so many waterproofing solutions to choose from. Unfortunately, with such a broad catalog of options, it can take you some time to determine what solutions may be best for your home.

Take the debate between vapor barriers and insulation, for instance. What’s the real difference between these two solutions, and is one really better at keeping your home dry than the other? If they’re both so good at protecting your home from excessive dampness, why not just install them both?

When To Use a Vapor Barrier

More often than not, you’ll see vapor barriers used in crawl spaces in the Virginia Beach area. A vapor barrier is a large plastic-like sheet that’s so dense, it not only keeps liquid water out of your home but gaseous water (and other gases) too.

When, though, should you consider installing a vapor barrier? If you have a crawl space or a small section of your basement you want to preserve, these barriers can be lifesavers. If you deal with mild to medium leaks on a yearly basis, you’ll want to talk to your local contractor about the barrier installation process. However, if you frequently have to deal with more severe leaks, it may be best to partner a vapor barrier with a more comprehensive solution, like a sump pump and interior French drain.

When To Use Thermal Insulation

Thermal insulation, comparatively, is designed with a dual purpose in mind. It primarily sits between the supports and plaster of your walls to create a heat barrier between the outdoors and your home. This way, it’s easier for you to keep the temperature in your home consistent.

Thermal insulation is most frequently made out of:

  • Fiberglass
  • Mineral wool
  • Cellulose
  • Polyurethane foam
  • Polystyrene

All that said, insulation is sold and packaged for different purposes. Thermal insulation, as mentioned, keeps the temperature in your home consistent. Comparatively, sound insulation is designed for music rooms and maintaining a noise level that’s considered acceptable or polite. While thermal insulation can also serve this purpose, it doesn’t do it as well as sound insulation does.

How, though, does your insulation interact with any rainwater that may sneak into your home through a cracked basement? Consider this: when water vapor or liquid groundwater comes into contact with your supports in the basement or crawl space, it’ll cause those materials to rapidly change temperature. To comply with the laws of physics, your supports will expand and contract on a molecular level and develop internal stress as a result. If that stress grows too extreme, your materials may be damaged, and your basement or crawl space leaks may grow more severe.

When you install thermal insulation, you better control the temperature of your supports, even if your home does start to leak. Pair that temperature control with hydrophobic insulation material, and you’ll have a waterproofing wall working double-time in your home.

That said, thermal insulation primarily protects your basement, not your foundation. If you’re dealing with a foundation leak instead of just a basement leak, you’re going to want to seek out some alternative waterproofing solutions to preserve the value of your home.

Installing a Vapor Barrier vs. Installing Thermal Insulation

As you can see, there are benefits to using a vapor barrier and benefits to using thermal insulation as waterproofing solutions. Neither of these solutions is completely comprehensive, but they can help you overcome any leaks that may appear in your home.

How, though, do the installation processes compare? Let’s break things down. To install a vapor barrier, you’re going to need to take the following steps:

  • Dry out your crawl space or a section of your basement.
  • Find the leak in your home.
  • Seal the leak with professional guidance.
  • Remove any old or damaged insulation that may impede the barrier.
  • Cut the barrier materials.
  • Place the materials along your floor and walls, only leaving gaps for electrical equipment.

Comparatively, installing thermal insulation requires the following from a crawl space professional:

  • Measure the spot you want to insulate to determine its surface area.
  • Place soffit baffles over your vents.
  • Prepare the insulation.
  • Place the rigid insulation panels on the walls and secure it in place with special fasteners, leaving essential features unimpeded.

As you can see, installing insulation is a little simpler than installing a vapor barrier. However, you can double down on your waterproofing solutions and install both at the same time.

The Benefit of Stacking Waterproofing Solutions

What’s the benefit of stacking your waterproofing solutions this way? For starters, you reap the benefits of your individual installations. However, a dual installation will also ensure that the individual solutions last longer. Your thermal insulation will serve as the first line of defense against basement cracks and internal dampness, whereas your vapor barrier will be able to catch any extra precipitation that makes it through the cracks.

Before you get started with the installation process, be sure to reach out to a Virginia Beach, VA, contractor to determine whether or not these waterproofing solutions are right for you.

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