Whether it’s remodelling, repair, or building a brand new home, you will want to install a new house wrap.
As an essential component of a home’s weatherproofing solution, the house wrap works with the exterior cladding of the house to protect the wall’s internal structures—and, by extension, the home as a whole—from the damaging effects of wind, rain, and humidity.
Not only is a house wrap a must-have for any home constructed in a particularly windy or rainy area, having it installed is actually a requirement in some areas as part of their building code for legal compliance.
Of the many house wrapping materials available on the market right now, two options have remained the most popular: Tyvek and Typar. And in this article, we will be comparing the two in terms of their characteristics to help you make a decision.
What is a House Wrap?
So what is a house wrap, anyway? To keep things brief, the house wrap is a water-resistive barrier or WRB made of one of various engineered materials.
The key feature of these materials are that they can block out large droplets of water like rain while allowing smaller water vapor particles to pass through from the inside out, to “breathe”. which lets the house regulate internal humidity while blocking out the weather.
What is Tyvek?
Tyvek is one of the modern standards for house wrap materials, and is made up of polyethylene fibers that are bonded together using heat and pressure to create a uniform sheet.
What is Typar?
Typar, meanwhile, is a composite engineered material with two layers—a thin film coating and a mesh backing made of a polypropylene fiber. The film coating gives the material its water and air resistance, but because of its low thickness, has to be supported by the mesh layer.
Which is Better, Tyvek or Typar?
The shortest answer we can give you is—it depends on the needs of your home and its environment.
Whatever opinions your contactor might have about them, there is no denyting that both Tyvek and Typar are highly effective house wrapping materials, and no one can definitively say that one is better than the other in all possible conditions.
That being said, the characteristics of Tyvek and Typar give them unique advantages as well as disadvantages, which means that certain materials may be better for certain homes with certain conditions. Let’s take a closer look at these characteristics to find out which house wrap is better suited for your home.
Weather resistance is a general term we use here to refer to both the wind resistance and water resistance of a house wrap material. While we could break it down separately, the fact of the matter is that inclement weather tends to be a combination of both, so we will leave it to you to decide which is better for your home.
In this respect, there are two standards that are used to gauge weather resistance: the AATCC 127 Hydrostatic Pressure Test and the TAPPI T-460 Air Permeability Test.
To spare you the complicated numbers, we can tell you that both Tyvek and Typar have passed equal wind resistance tests, but Typar has better water resistance compared to Tyvek (865cm of water pressure vs 250cm). However, Tyvek does have a built-in drainage plane, which allows it to handle strong flow rates more efficiently.
Permeability refers to how much water vapor is able to pass through a material—in more practical terms, it indicates the breathability of the house wrap and how well it will be able to help the house control its internal humidity.
For your reference, Tyvek has a permeability rating of 56 while Typar has a permeability rating of 7. Knowing this, you will want to choose Tyvek if you want better breathability.
As the name suggests, UV resistance refers to how long the house wrap is able to maintain its integrity when exposed to UV light, such as from the sun. With this in mind, Tyvek has a UV rating of 4 months while Typar has a UV rating of 6 months.
Now, it should be noted that the UV rating doesn’t mean that the house wrap can only last that long before falling apart. House wraps are installed behind wood or vinyl siding, which protects the wrap from UV for as long as the siding lasts.
Instead, the UV bating is a good indicator for your building contractor, as it gives them a timeframe for how quickly they need to install the house wrap and siding. To sum up, UV resistance is not something you should worry about too much.
Surfactants (short for surface-active agents) are substances that lower the surface tension of things like water, allowing it to better slide off of surfaces but also enter micro-porous ones like house wraps.
Soaps, oils, and detergents are just a few of the most common chemicals that either act as surfactants or have them as part of their ingredients. As such, resistance to these chemicals are generally desirable if you want the house wrap to stand up better to cleaning and chemical exposure.
The composite structure of Typar gives it resistance to surfactants, unlike Tyvek.
Last but definitely not the least of your considerations in house wrap is its durability. However, the effective durability of any given house wrap not only depends on what house wrap you use, but how suitable it is to the environment that it will be working in.
For example, the better permeability of Tyvek allows it to last longer when installed on homes in humid regions, as the house wrap can better curb the growth of mold and mildew that can hamper the house wrap.
On the other hand, Typar is able to resist surfactants and has better water resistance, which means that it is preferred for use in regions with more substantial rainfall.
Again, the final decision of which house wrap to use is up to you; we strongly recommend going through your options with your contractor to figure out the house wrap that works best for your home improvement project.