When most of us think about the construction materials we use for our building envelope, we probably think of 2x4s, plywood sheathing, and a hammer and nails. Using tape for sealing up a building envelope might seem like a slapdash solution to careless construction methods. However, high-performance building tape offers a practical, efficient, and easy-to-use solution to improve our homes' airtightness.
Passive homes are widely considered to be the leading standard for energy efficiency and healthy indoor air quality. One of the foundational principles of these types of homes is a completely sealed and airtight building envelope. Passive home builders often use high-performance tape to eliminate even the slightest potential sites of air leaks. Whether you are building a new home or considering a passive house retrofit to improve your home's energy efficiency and thermal performance, the high-performance tape should be on your shopping list the next time you head to your local hardware store.
The building envelope is defined as the exterior shell of a house that repels the elements. The envelope is an under-appreciated engineering system that combines structural integrity, moisture control, temperature control, and air pressure boundaries into a single design strategy. "Loose" building envelopes do allow for natural ventilation in the home. However, they also become drafty, uncomfortable and make your HVAC equipment work harder to maintain your home at a comfortable indoor temperature. Almost half of the US's total household energy use is dedicated to heating and cooling our homes. So, sealing the building envelope is widely seen as one of the best ways to reduce our households' energy use and carbon footprint
The relationship between building envelopes and the energy efficiency of our homes is easy to imagine. The cracks, gaps, and fissures around our home allow the conditioned air inside our houses to escape. At the same time, they allow the unconditioned, outside air into our homes. Even if you have chosen the best, high-performance insulation and have gone above and beyond the recommended R-values for your region, a leaky building envelope essentially renders that insulation ineffective. When temperatures are below zero or above 100 degrees Fahrenheit outside, even a small gap in your building envelope can lead to drastic changes in your home's interior temperature.
Most people associate building envelope "leaks" with small gaps around door and window frames. Simple weatherstripping kits are usually a fast and easy solution to help you get rid of the cold drafts associated with this common winter problem. However, building envelope leaks often occur in other, harder-to-spot areas. Leaks between the roof and the wall assembly or between the wall and a window system are common, especially in older homes that have settled.
Tighter building envelopes rely on meticulous building processes to eliminate air leaks. Contractors who focus on a tight building envelope will use higher amounts of insulation, caulk, adhesive tape, sealants, energy-efficient windows, and other building elements that give homeowners more direct control over their home's temperature and humidity levels. Homes with a tight building envelope generally consume much less energy leading to lower utility bills. However, they may require mechanical ventilation devices such as ERVs or HRVs to improve indoor air quality. High-performance building tape is an essential building component in helping to increase the tightness of building envelopes.
High-performance building tape refers to various adhesive tapes designed to seal overlaps, gaps, and connections between building components. These products are usually used during the building or renovation project to offer permanent, airtight bonding between component layers, vapor control layers, component joints, and other building systems. High-performance building tape provides a practical and lightweight strategy to seal a wide variety of different types of building joints and overlaps, ensuring the maximum airtightness for your building envelope.
Sealing the joints, junctions, seams, and overlaps of various building materials during the construction process requires different adhesive tape types. For example, high-performance building tape used to seal the overlaps of a moisture barrier placed on top of plywood sheathing will need to be highly water-resistant. Other types of building tape designed to seal connections inside the building envelope do not offer the same water resistance level.
There are dozens of different kinds of high-performance building tape, including options that have been specifically designed for use on:
According to some experts, energy losses due to air leaks in a home's building envelope can range from 10 to 50 percent of total heat loss. A house with a significant amount of air leaks around door and window frames, exterior sheathing, and foundation connections is most likely spending a lot of money on its heating and cooling bills. Even with high-quality insulation that goes above and beyond the recommended R-values for your region, major air leaks will essentially render that insulation ineffective.
It is nearly impossible to put a number on potential savings associated with improving your building envelope's airtightness. However, several examples of passive homes with an utterly airtight building envelope spend $0 on their monthly energy bills. For example, this Denver townhouse combines an airtight envelope with other net-zero construction aspects. They save significant money on their monthly energy bills, even during the harsh Rocky Mountain winters. Using high-performance building tape to reduce air leaks will undoubtedly help reduce your monthly energy bills.
High-performance building tape is a relatively new product used to seal home building envelopes, so there is no definitive answer to this question. However, most contractors believe that high-quality building tapes like SIGA and others should last a lifetime, potentially for a century. It is essential to find quality building tapes that offer maximum adhesive quality. Also, you need to make sure to choose the most suitable building tape for your specific application. For example, using non-water-resistant building tape for exterior applications will most likely reduce its durability and performance.
Each type of high-performance building tape will have further instructions for proper installation and use. You apply most of these tapes by hand in the specific joints and overlaps where you need to cover. Double-sided adhesive building tapes will have a protective liner on one side. It will help if you peel this off before adhering, such as in the case with connecting overlaps of moisture barriers. Some products also come with a hand tape applicator that can efficiently and accurately apply your high-performance building tape for the specific use you need.
There are dozens of different companies producing high-performance building tapes for other uses and applications. The best and most renowned brands include:
This Swiss-based company offers dozens of different types of high-performance building tapes, including options for the secure sealing of component joints in solid and metal structures, airtight indoor connections, double-sided tape for control layers, and rainproof tape for exterior applications.
3M also offers a wide variety of high-performance building tapes for exterior and interior applications.
Another innovative product is the Silver tape offered by Lamatek. This high-performance building tape provides excellent long-term holding power. It is perfectly suited for both interior and exterior applications.
High-performance building tape offers a cost-effective way to improve the airtightness of your building envelope drastically. SIGA, 3M, Lamatek, and others provide a wide range of products that can replace mechanical fasteners like rivets, screws, spot welds, and (potentially stinky) liquid adhesives on a variety of surfaces. More airtight building envelopes can quickly drive down your energy bills and help avoid moisture damage that can lead to issues for your home's insulation, framing, or other structural components. The only real downside associated with high-performance building tapes is that, in most applications, they are best used during the initial construction phase or significant renovations.
Tobias runs an agroecology farm and a natural building collective in the mountains of El Salvador. He specializes in earthen construction methods and uses permaculture design methods to integrate structures into the sustainability of the landscape.