House wrap is necessary to keep water and drafts from entering your home. A water-resistive barrier (WRB) it keeps water damage and mold at bay. When house wrap and flashing are used with windows, it creates a moisture and air barrier while also increasing the home’s energy efficiency. In this article, we’ll cover how to install house wrap around existing windows, the tools you’ll need to do it yourself, why it’s important, and more.
What is House Wrap?
House wrap is a synthetic material that covers the exterior of your home. It’s installed behind the siding, but over the sheathing of the house. When installed correctly, house wrap can keep moisture, mold, and drafts out of your walls and home. If it’s not installed properly, mold can creep into the walls and potentially cause rot. House wrap is usually added before new window installation, especially for old-fashioned windows, but it can be added to existing windows as well, especially during home improvements.
Why Would I Want House Wrap Around My Windows and Doors?
Maintenance is required to keep our homes in great condition. It’s easy to get accustomed to that draft, excess moisture, or different temperatures in different rooms and simply learn to ignore it. In old houses or with old windows, homeowners often expect the odd draft or two. However, if your home wrap is breaking down, you could be letting moisture, air, and mold in. Over the long-term, this could do serious damage to your house and cost you both in repairs and in energy expenses.
Doors and windows are the most common areas for drafts and moisture to sneak through. House wrap is a necessity to keep your home comfortable, while also protecting the walls and structure of the building.
Without properly installed house wrap, you’re also facing higher energy costs. More energy is required to compensate for that loss of heat during the winter or you may need a humidifier to keep out the humidity in the summer. In addition, the moisture and mold could wreaking havoc on your walls, resulting in expensive repairs down the road.
Can I Install House Wrap Around an Existing Window?
You can install house wrap-around existing windows in some situations. It depends on the type of exterior facade you have. The more complicated the facade, the more complicated it is to install house wrap. For homes with brick or stucco, installing house wrap can be very difficult. On the other hand, it’s much easier for houses with sidings such as vinyl, aluminum, hardboard, T1-11, shakes, and other forms of lap siding.
No matter the facade of your home, the goal is to extend the house wrap 12” beyond the window frame.
The steps required to install house wrap around existing windows will vary slightly from window to window, but the basic process will remain the same.
How Does the Type of Window Affect House Wrap Installation?
Generally, the steps to install house wrap will generally remain the same no matter the type of window or siding you have. However, you will need to tackle the job slightly differently for certain types of windows, including:
Wood Counterweighted Windows
Wood counterweighted windows were some of the first window designs that did not require hinges. However, these windows lacked any form of flashing and being made of wood, tended to allow leaks around the frame. Since these windows do not include a mounting fin, the house wrap and tape should extend from the rough opening, over the gap, and onto the window frame. In most instances, removing any trim, such as brick molding will make the job easier.
Vinyl and Aluminum Replacement Windows
Both vinyl and aluminum replacement windows are designed to be installed within the existing frame of an older window. Due to this design, replacement windows generally don’t include a mounting fin and are simply attached with screws inside the existing window frame. As such, new house wrap will not extend to the actual window, but to the original window frame. If the window has brick molding surrounding it, the molding should be removed and the new house wrap installed under it.
Vinyl and Aluminum New Construction Windows
Adding house wrap to a home with new construction windows, whether vinyl or aluminum, is very simple. In most circumstances, the nails are gently removed from the nail fin one side at a time and the house wrap is slid underneath. The order is important, so the bottom should be installed first, then the sides, and lastly the top. The nail fin is then reinstalled and tape is applied over the nails and fin.
What Type of House Wrap Can You Install?
Before installing house wrap, you will need to decide on which product you will want to use. At a minimum, it should meet building codes in your area.
When purchasing house wrap, you should look for:
- Durability: Consider how the material will stand up against the elements, such as hot and cold temperatures. The house wrap should also be tear-resistant.
- Water resistance and vapor permeability: Your choice should have a vapor permeability rating of at least five to meet building codes. Water resistance also prevents water from getting trapped and allows water to be properly drained.
- Ultraviolet (UV) stability: If the wrap is going to be exposed to the elements for a few weeks, lack of UV resistance can cause the material to break down.
Your home’s construction could dictate the type of house wrap you will need to install. Common options include:
- Asphalt felt: A popular choice, it can keep water at bay, but it doesn’t hold up against direct sunlight for long. It will have to be covered by siding quickly.
- Grade D building paper: This type of house wrap is often used with stucco exteriors and has strong vapor permeability. It can deteriorate, though, so two layers are recommended.
- Liquid water-resistive barrier: This is applied with a sprayer or roller to create a coating around the home and windows. Installation takes longer, and it is one of the more expensive options.
- Polyolefin fabric: A reliable, easy to work-with choice that is tear and water resistant. However, it doesn’t work well with redwood siding, stucco, or wet cedar siding due to surfactants.
- Integrated WRB Sheathing: A durable choice, it reduces the chances of getting water trapped inside the home. However, like the liquid water-resistive barrier, it’s a more expensive option.
What Are the Best Brands for House Wrap?
The most commonly used brand for house wrap is Dupont’s Tyvek but there are other options available. Here’s what you need to know about the popular options:
Tyvek from DuPont
Tyvek house wrap from DuPont is by far the most popular house wrap product for homeowners and construction companies. Since it’s non-stick, it doesn’t require staples and nails, but will need seam tape. It’s permeable, cost-effective, and is water-resistant. While Tyvek does improve a home’s energy efficiency, it’s not drainable.
DuPont’s FlexWrap is a self-adhering flashing tape that can be used with Tyvek to seal corners, including those around windows.
Blueskin VP100 House Wrap from Henry
Henry’s house wrap used to only be available to commercial vendors, but is now available for homes as well. Blueskin VP100 is water resistant, vapor permeable, energy efficient, and self-sealing, so like Tyvek, it doesn’t require staples or nails but it also doesn’t need seam tape. Blueskin VP100 should not be exposed to direct sunlight for more than 150 days.
Hydrogap House Wrap from Benjamin Obdyke
Hydrogap House Wrap offers drainage and breathability to homes. In fact, it’s rated to drain two times faster compared to competitors. It’s also easy to install and doesn’t require seam tape. However, like Blueskin VP100, it can’t be exposed to sunlight for long.
Typar from Fiberweb
Typar from Fiberweb enhances a home’s energy efficiency and blocks water and moisture from entering the wall cavities. It’s also known to withstand heavy winds thanks to its resistance to tears, and Typar uses 25% post-individual recycled content. The downside of Typar, though, is its lower permeability rating and breathability, especially compared to Tyvek.
How To Install House Wrap Around an Existing Window
Before starting your DIY project, you will need to gather the right tools. The materials you’ll require depend on the type of house wrap you are using, but generally you should collect:
- House wrap
- Staples
- Nails
- Seam tape
- Hammer tackle
- Tape
- Nail puller
- Caulk gun
- Flashing tap
- Pry bar
- Measuring tape
- Box cutter or utility knife
- Primer (if you have wood siding)
For homes with brick or stucco, you will only want to install house wrap around existing windows if there is water damage. For homes with vinyl, aluminum, and similar types of siding, you can follow these steps:
- Step 1: Remove the Siding
Generally speaking, most siding can be removed with a combination of nail pullers, hammers, and pry bars. Vinyl and aluminum sidings are usually installed with galvanized roofing tacks or staples. Removing these fasteners is a matter of gentle persuasion and patience, with the goal of re-installing the siding without damage. Once the edge of the window can be seen, the house wrap can be installed.
- Step 2: Measure and Cut the House Wrap
The easiest way to measure and cut the house wrap is to cut the material into four (4) 12” strips. Remember: measure twice, cut once! Next, each strip is cut to length by adding 12” to the length of the window. For example, if the window is 30” x 30”, the installer will cut four strips, 12” by 42” (30 + 12). The extra 12” is divided into two. This ensures that an additional 6” of house wrap extends beyond the window in all four directions.
- Step 3: Install the House Wrap
Starting at the bottom, the first strip of house wrap is placed horizontally over the joint between the window frame and the rough opening and taped into place. Next, the second strip is installed vertically on either the left or right side (either is OK) and again taped into place. Then the other vertical side is done the same way, making sure to overlap the previous strip by 6”. Lastly, a strip is installed across the top of the window and the taping process is repeated. At this point the siding can be carefully re-installed.
Frequently Asked Questions
Should you add house wrap to windows if the home has brick or stucco?
Generally, no, you should not add house wrap to existing windows if the home has a facade of bricks or stucco. The only exception is if the lack of house wrap is causing water damage to the home.
Should you hire a professional to install house wrap or can you DIY??
Improper installation of house wrap can cause water damage and poor energy efficiency within a home. If you’re not confident in your abilities to install it correctly or choose the right material, it’s highly recommended that you work with a professional. However, it is entirely possible to DIY.
Is house wrap absolutely necessary?
No, house wrap is not absolutely necessary. However, there are benefits to installing it, such as reduced moisture and enhanced energy efficiency. In some areas, house wrap may be legally required.
Is window flashing necessary with house wrap?
Yes, window flashing is another layer that helps to prevent water from getting behind the house wrap.
Can you use caulk instead of window flashing or house wrap?
Caulk should be used with window flashing and house wrap, but not on its own. Over time, caulk can crack and shrink, allowing water to intrude into a home. It also doesn’t have the same drainage and water resistance that comes with window flashing and house wrap.
