Law and Order is required in any business industry. The construction industry is one of the most important sectors that need delicate attention, owing to the fact that the lives of occupants matter. Without the use of building codes, there will most probably be many problems arising from compromised quality of materials used by contractors and homeowners. Knowing the code that applies to the use of wraps in your project, goes a long way to help you know which particular material to select from available options in the market.
Because these codes are updated on a timely basis, builders are expected to pay close attention to specific details. These codes range from air resistance, water resistance, vapour permeability, to flammability, just to mention a few.
The Evolution of Building Codes
To begin with, building codes evolve with respect to the trend of available materials as at the time that the project was executed. So, applicable codes used 10-20 years ago are no longer the same as current applicable codes within the last 2-3 years. Materials have evolved over time and technology has helped to improve the quality and properties of these materials.
For instance, in the 1999 manual edition, felt papers were the standard recommendation for weather protective barriers to be done prior to the application of Vinyl sidings.
In contrast, by 2004, this manual was reviewed under important notes that identify vinyl sidings as a material that allows external wall assembly to breathe. Thus they must be placed over weather-resistant barriers. Another instance is the International Residential Code (IRC) for the construction of homes as of 2003 which did not require the installation of water-resistant barriers. Whereas, updated code policies in 2006 make provision for sheathing papers.
In 2018, the International Building Code (IBC) of “Weather Protection” for exterior walls, itemized all specifications that secure the envelope of exterior walls. This code enumerates all the measures required to prevent the saturation of water within the cavity of walls by providing water-resistant barriers behind exterior thin coverings. It also outlines the need for eliminating moisture from exterior walls.
Water resistant barriers (WRB) which are shields preventing air and water from penetrating building interiors are clearly identified. While air barriers are to be made available to cater for air penetration, water barriers are expected to be available to prevent moisture penetration.
In cases of advanced high rise buildings, where higher performance levels are expected along the envelope, WRBs are popularly required and properly spelt out. It is very significant to ensure that all the interior spaces of the building are secured from external environmental factors.
Key Performance Qualities and Features
The key performance quality and features of building wraps are as well clearly captured under the International Code Council-Evaluation Service (ICC-ES). These features and properties required for house wraps are identified so as to know which particular product or materials is best suited for a particular project.
Permeability
In the selection of house wraps, ideal perm ratings range between 10 to 20 perms to guarantee the makeup difference between water penetration and the drying abilities.
Volatility
To meet up with flammability codes, the fire rating for water-resistant barriers is expected to fall under class A.
Tear resistance
The tenacity and tear resistance of house wraps are expected to withstand installation pressures without any reduction in the integrity of their ability to resist water.
Moisture resistance
House wraps must be able to overcome all forms of laboratory tests that measure their resistance to moisture impact and the pressure force of gravity influenced by water. Not less than one layer of approved WRB must be applied on exterior wall sheathings with prescribed flashing according to specifications. The citation by IRC R703.1.1 for water resistance states; “The exterior wall envelope shall be designed and constructed in a manner that prevents the accumulation of water within the wall assembly by providing a water-resistant barrier behind the exterior cladding … and a means of draining to the exterior water that penetrates the exterior cladding.”
Installation
The application of house wraps are expected to meet up with inspection criteria for project approvals. Any leakages pose great threats to the integrity of external cavities. As a result, water-resistant barriers are required to be in accordance with stipulated codes that prevent the growth of fungi and decay. This code also covers the envelope works done on exterior walls which expects installations to be carried out in ways that prevent water saturation within the wall cavity. This installation code specifies the conditions and status of house wraps before usage. To mention but a few of these regulations before installations; Tar papers must be free from any form of holes and breakages, exposure limits must not be exceeded before application is carried out, and installation procedure must follow stipulated directions for application.
Manufacturers’ specifications
Manufacturers are required to clearly specify the properties, quantities and qualities of aggregate composition of products where need be, so contractors have the room to decide suitability of materials with respect to proposed projects. Manufacturers are also expected to identify clearly for users the instructions required to be followed in the application of their products. The manufacturer’s instructions should cover the dimensions of all vertical and horizontal overlaps in ways that make the wraps appear seamless and impenetrable to external elements. Moreover, plastic and metallic cap fasteners are to be properly defined in order to protect these wraps from damage during installation and also prevent the fasteners from the likelihood of tearing through the house wraps.
The Application of Building Codes
Building codes play a major role in guarding the standards for wraps to be applied within the construction industry. Moreover, it protects the structural integrity of claddings and materials used in projects by specifying relevant details for quality, properties, and characteristics. Without building codes, there will neither be any standardized procedure for installations, nor suitable measures used in the application of house wraps. Thus, construction professionals and homeowners need to keep themselves informed and abreast regarding the trends of regulatory codes, relevant to their projects.
