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Waterproofing Your Home: Vapor Barriers, Thermal Insulation, or Both?

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If you think dealing with a crawl space leak is bad, just wait until you see your waterproofing options. While it’s a relief to know that you’re able to choose your solutions from a vast catalog, it can be overwhelming to try and understand how the solutions differ from one another.

Take vapor barriers and thermal insulation, for example. Both will protect your crawl space from minor to medium flooding – but how can you know which one is best for you?

Let’s break down the differences between these two waterproofing solutions and see if you really do need to choose one over the other.

Cutaway illustration of a basement with exposed wooden beams, insulation, and a small blue dehumidifier.

The Benefits of Thermal Insulation

When you’re thinking about the different ways to waterproof your home, insulation may not be the first trick that comes to mind. Thermal insulation, however, does more than lower your energy bills.

Thermal insulation comes in handy for two reasons. For starters, when you select a hydrophobic material to insulate your home with, you create a physical barrier between the outdoors and the indoors. Some of the most common materials used for thermal insulation include:

Alpha crew member installing insulation in crawl space.
  • Fiberglass
  • Mineral wool
  • Cellulose
  • Polyurethane foam
  • Polystyrene

However, thermal insulation also helps you keep your crawl space at a consistent temperature. Why does this matter? Because when the brick, concrete or other materials making up your home change temperatures too quickly – often when exposed to excessive hydrostatic pressure – they will expand and contract accordingly. The stress from these changes can cause your foundation or crawl space to develop cracks, followed by leaks.

Installing Thermal Insulation

Thermal insulation is also relatively easy to install, and it’s best to reach out to a professional contractor who will be able to help you protect your home:

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

The Benefits of Vapor Barriers

Should you choose to install thermal insulation over a vapor barrier, though?

Vapor barriers are made of thick plastic-like material that’s so dense, it doesn’t allow most gases through. This means that, upon installation, your crawl space will be safe from moisture in both its liquid and gaseous forms.

To install a vapor barrier, you’re going to need to:

Alpha crew member installing vapor barrier in crawl space.
  • Dry out your crawl space.
  • 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.

It is worth noting, though, that vapor barriers aren’t as good at protecting your foundation as they are protecting other elements of your home. Why? Because most vapor barriers don’t reach down into your foundation. Nor do vapor barriers have all the thermal impact that insulation does.

That said, vapor barriers are among the best waterproofing solutions you can use in a leaking crawl space. Whether or not you want to install one will depend entirely on what your home needs.

When To Combine Waterproofing Solutions

Sometimes, it’s not a matter of choosing one waterproofing solution over another. If you frequently deal with medium to severe leaks, you may want to consider stacking a vapor barrier with thermal insulation. After all, you may already have to replace your insulation when installing a vapor barrier. When you use hydrophobic thermal insulation alongside your barrier, you both preserve the life of that barrier and reap the rewards of that extra protection.

Think that a combined solution will work in your home? Talk to one of the contractors operating in the Florida area for a free quote on their installation services.

Don’t wait for hurricane season to turn your crawl space into an indoor pool. Reach out to your local crawl space repair contractor today to see what you can do to protect your home.

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