Frequently Asked Questions
Q: What is a Passive House?
A: Here are the principles of passive building as described by Phius, North America’s leading Passive House training and certification organization:
Using continuous insulation throughout the building envelope to minimize or eliminate thermal bridging (a pathway for heat to get in or out of a building)
Building a well-detailed and extremely airtight building envelope, preventing infiltration of outside air and loss of conditioned air while increasing envelope durability and longevity
Employs high-performance windows (double or triple-paned) and doors - solar gain is managed to exploit the sun's energy for heating purposes in the heating season and to minimize overheating during the cooling season
Using some form of balanced heat-and-moisture-recovery ventilation to significantly enhance indoor air quality
Minimizing the space conditioning system because of lower space conditioning loads
Enjoy this 90-second video explaining Passive House design.
Q: How much does it cost?
A: Building to highly-efficient, passive house standards means that more material is used than when building to code. (Because Tooketree builds with natural materials, it also means we sequester more carbon in the building which is great.) The building enclosure is very well insulated with extra thick walls. On average, the cost to build a Passive House enclosure made with natural, healthy materials is about 10-15% more than a minimum code-built home. However, dramatic energy savings will be noticed immediately when a passive house is compared to a code-built home. The initial investment may be recuperated in as little as five years due to savings on energy bills which can be 80-90% heating and cooling costs. Given the energy efficiency and the performance of the building, the resale value of a passive home is higher than a conventional home. Factoring in quality construction, high-performance air and moisture controls, and more durable mechanical systems, the total cost of ownership can be significantly less over 10-20 years.
Data shown from SEEFAR Comparative Building Assessment Report by SRP Canada, 2018.
Q: Do you design the homes?
A: Tooketree has design capability and we also work with outside designers and architects. We’re more than happy to panelize your custom designs. We often partner with the design firm Passive Design Solutions (PDS). PDS has a catalogue of over 60 unique, attractive designs to suit any aesthetic and lend themselves very well to use of our panels.
Q: How is cellulose insulation fireproof?
A: It is not fireproof, but it is fire-resistant. Cellulose insulation contains borax which provides flame resistance and combustion retardancy. In fact, cellulose insulation is one of the few building insulation products that has a Class 1 Fire Rating. It also has a flame spread of 25 or less. Walls with cellulose insulation are one-hour (or greater) firewalls. This allows the product to help control the spread of fire in homes and buildings where it is used to insulate attics, walls and other spaces. It also has a very low smoke development index level.
By design, the fire retardant in cellulose insulation slows the spread of flames through insulated assemblies to help localize the fire in structures. This allows occupants more time to escape to safety when a fire is detected and gives the fire company more time to reach the scene and limit damage.
In contrast, the foam insulations that are commonly used in conventional buildings are made of petrochemicals. They contain large amounts of highly toxic substances which are marketed as flame retardants, though studies have found them to be ineffective. When these petroleum-based products and their toxic “fire retardants” burn, they release carcinogenic forever chemicals into the environment (which they do during manufacturing, installation and normal use as well). Because we build with natural materials that contain safe fire retardants, (Borax is a mineral and salt combination derived from boric acid) harm to human health and the environment is mitigated in the case of a fire.
References:
Cellulose Insulation Manufacturers Association: Firefighters Guide for Cellulose Insulation Building Fires
IPEN (International Pollutants Elimination Network): A Public Interest Guide to Toxic Flame Retardant Chemicals
San Antonio Statement on Brominated and Chlorinated Flame Retardants
Q: Doesn’t natural insulation breed mould?
A: Our CSA-certified air-tight, water-resistant panels are sealed against mould spores. Mould requires moisture to grow, and our clean, dry manufacturing facility allows us to eliminate exposure to mould during the panel fabrication process. Wood products and other materials are scrutinized before use. We use high-performance, smart membranes for both our outdoor Weather Resistive Barrier (WRB) and interior Vapour Control Barrier. These membranes prevent moisture from entering the walls, floors and roof of the building. Should any moisture happen to find its way in, the smart membranes will allow it to escape, protecting the enclosure. Our high standards for quality earned CSA certification for our SEED panels.
Borax is a natural mould inhibitor, and a small amount of borax is added to the cellulose at manufacture.
Q: Isn’t cellulose insulation inviting pests such as termites and rodents?
A: Termites and rodents are, unfortunately, a potential issue for any building that includes wood, be it for structural or finishing purposes. The borax in cellulose insulation can kill and repel bugs, helping to keep your home free from pests. A well-installed foundation that keeps the building enclosure away from the soil, and good practices in landscaping and maintenance around the home will help prevent pests. Our panels are fabricated and sealed in a controlled environment which protects them from exposure to pests. Also, our floor panels are lined with rodent screens on the exterior side to inhibit pests.