The first time I used a self-adhered water resistive barrier was in 2019, on my own home. I had recently purchased a 1950’s vintage Cape Cod design fixer upper that was built using board sheathing covered by 15 lb. asphalt impregnated felt. I knew I wanted to improve the water management and air tightness of the structure but didn’t want to upgrade the sheathing. I had been researching self-adhered WRB’s and decided that option would be the best fit based on what I was trying to accomplish.
For the exterior renovation at my home, the Henry Blueskin product was installed over the board sheathing. The assembly also includes a 3/8-inch furring strip for a ventilated rainscreen.
Missing a detail when working through an unfamiliar assembly can be easy to do. Getting your head around the movement of water, air, and the thermal boundary with all of the parts and pieces that are required to make the structure often requires more information than can be shown in a simple plan or elevation. I often find myself drawing in 3-D using a modeling software or even going as far as building a mock-up of the assembly. Sometimes both are needed.
If you are an architect, which I am not, you’ll have the software tools to make professional, photo realistic drawings. I do have some formal training in drafting, but that was decades ago, CAD was new, and my instructor believed in drawing by hand first, then move to the computer. Some of my past designs were simply done on paper or with an inexpensive CAD program, which can work, but not very impressive when trying to sell a client on a design.
This hand drawing is my original design for the concreteless slab on grade home showing the floor system. Later, with the help of SketchUp, the design was transformed to this.
Testing the air barrier or air control layer of a home has traditionally been done using artificial pressure created by a fan, commonly referred to as a blower door test. Why You Need Blower Door Testing – Northern Built The advantage of using an air pressure differential testing is twofold, we can quantify the building tightness (CFM50, ACH50 or CFM/ft² of surface area) and locate deficiencies in the air barrier. Finding the air leaks can be done by watching for fluttering drapery or spiderwebs, feeling for air leaks, using synthetic smoke created by smoke generating tools, by thermal imaging, or measuring pressure differentials between spaces inside the building enclosure using a manometer.
I was recently contacted by a friend who wanted to add a kitchen range exhaust hood to their 100-year-old home. They were looking for insight on how the fan might be added, where the ducts could be located, sizing of the system, and any other concerns that might need to be considered. One of my first questions was what equipment was presently used for space heating and water heating. A critical question that needs to be considered before adding any type of exhaust system. Why? Health and safety of the occupants.
Continue reading “Considerations When Adding Exhausting Equipment to an Existing Home”
The building science community talks a lot about control layers. I’ve written on the topic several times, basic overview of these principles which can be found at: A Crash Course on the Four Control Layers. Let’s take a deeper look at water resistive barriers (WRB) and how windows and doors need to be integrated into the WRB.
As builders and homeowners, we are interested in how a window or door performs, their longevity and durability, and how easily they install, and of course the cost. Have you ever given thought to how a window or door is tested by the manufacturer?
I recently had the opportunity to tour Andersen Windows and Doors research and development department, a place called the Garofalo Center for Research, Development and Innovation. This is the facility where, in the words of Andersen, they “test to failure”. Stated in another way, they don’t test to see if a product simply passes a required testing standard, Andersen wants to know at what point their products fail. Continue reading “How a Window Manufacturer Tests Thier Products”
What is an energy code? Energy codes are part of the building code that regulates how heat and energy are used in a building. By now, most builders understand there are minimum insulation levels, in walls, floors and ceilings. There are also requirements in how windows and doors perform. Air tightness testing and mechanical system performance (both in space heating and water heating) are also part of the energy codes. Local jurisdictions adopt (sometimes modify) and enforce these codes. Updated energy codes are released every three years. The 2024 IECC has been released, but most jurisdictions are looking to adopt the 2021 version, which you can read here: 2021 INTERNATIONAL ENERGY CONSERVATION CODE (IECC) | ICC DIGITAL CODES (iccsafe.org)
I purchased my first thermal imaging camera back in 2009, it was an Extech i3 (made by Flir). The $1200 camera had a resolution of 60×60, total pixels of 3,600 and shot photos only in thermal (no digital photo overlay). If you don’t understand any of those terms, that’s okay, you will have a basic understanding of how thermal imaging works by the end of this article. Oh, and by the way, you can now purchase more than twice the camera I had in 2009 with half the cost.
I was a builder for more than 10 years before I attempted my first above code building project. There was an order in the way I built early in my career that usually kept my projects moving smoothly. That schedule went out the window with my first attempt at constructing a higher performing home.
Integrating high levels of air tightness, greater R-values, along with other elements to improve performance can result in assemblies and installation details going out of order from traditional construction practices. The easiest and most logical construction schedules often need adjustments.
I purchased my home in the fall of 2018. I could have decided to build something new or forgo all the maintenance that comes with home ownership and rent. Instead, I chose to purchase an older home that needed updating, both in appearance and performance.
The 24’ x 32’ home was built in 1952, a Cape Cod design with the normal problems of a Cape Cod, attic knee walls that were both inside and outside the air control layer. There was some evidence of past water damage and a few old clips on the roof where a heat tape would have been placed, suggesting an ice dam issue. The high efficiency natural gas forced air furnace appeared to be from the 1990’s, the same year as the electric water heater. There was also a natural gas fireplace in the small living room. There was a weird-shaped room on the main level (behind the sun and where the sliding patio door is located, 9’ wide by 24 feet long. Two bedrooms, and a bathroom were located upstairs, a bathroom on the main level, and an area in the basement that had an egress window well that would support another bedroom. Continue reading “How to Prioritize Energy Upgrades to an Existing Home-Part 2”
