Re-Build Better in a few steps
Sustainable, Durable & Efficient Retrofits
I have been in, around and on top of Green Building in Alberta for more than 8 years as a designer, consultant and inspector on some of Alberta’s most sustainable homes. As an instructor for R-2000 builders, and a LEED Canada for Homes Provider and Accredited Professional, draw from great experience, training and an excellent team of colleagues in tackling the challenges of building homes that are forward looking, durability and energy efficient.
My hope is that the following collection of advice and suggestions help you in looking towards a sustainable future where our homes are part of the solution, less at risk to disaster and more durable against the elements. This is general information only, each home and situation is different and readers must contact a professional contractor or designer consultant (like 4Elements) for specific and detailed information.
My recommendations are based on recent National Building Code recommendations and the LEED Canada for Homes program. As a guide for sustainable homes, LEED is a premier rating system for measuring sustainable, durable and energy efficient homes, and it is considered the best reference for best practices.
Insulation
Ideally, new insulation should be non-absorbent foam types, either type IV extruded polystyrene (XPS, sold often as dense pink or blue sheets of foam), or 2lb polyurethane spray foam. Using insulation like this in flood susceptible areas will simplify future clean up. These products offer great moisture protections, higher R-values per inch and do not absorb water. Most homes may only have R12 batt insulation, which effectively works at an R-value of 10 when framing is accounted for. Heat lost through the basement could be cut in half with the use of 4" of foam with an effective R-value of 21.
Spray foams can easily be installed around existing framing and directly onto existing concrete, once clean and dry.
Additional notes:
- Spray foams should only be installed by qualified, certified technicians only. Surfaces must be contaminate-free and dry before application or the foam will fail.
- Flooding can cause structural damage so your foundation should be inspected by a qualified Engineer.
- Look ahead to upcoming code changes. R12 batt insulation for basements is no longer considered adequate, except in Alberta which tends to lag behind the rest of the country in our Building Codes. New National Building Code requirements are calling for insulation in basements to perform better than R20 batt insulation.
Modern building science looks at basements differently than when old homes were built. Current recommendations for the Canadian climate call for added insulation, better air tightness, but no poly behind the drywall where it is possible for moisture to collect. Poly is a vapour barrier, and often traps moisture behind, often causing damage. New products can be used such as “smart vapour barriers” or drywall with vapour barrier paint. These prevent most moisture movement, but do allow some drying when needed, preventing the “Double Vapour Barrier” issues that can cause problems.
Furnace and Hot Water Tanks
If your furnace or hot water tank needs replacing, this may be a great opportunity to make one of the quickest pay back upgrades possible. Look for ENERGY STAR ratings and condensing type equipment. These new units have sealed combustion; this means that gasses from the furnace or hot water tank can’t leak backwards into the home. It is not recommended to replace a damaged boiler, hot water tank or furnace with the same chimney venting system that was likely original. These systems are the reason we install carbon monoxide detectors to prevent carbon dioxide poisoning deaths, which claim the lives of Albertans every year.
Air sealing
Basements are a major source of cold air leakage in homes and air leakage typically makes up the larger proportion of energy loss (i.e. your energy bill) of any other area of the home. The basement rim joist area where the floor framing meets the concrete is often a particularly leaky area. Surprisingly, the basement slab is a major source of air leakage where left unsealed at the slab edge or unsealed plumbing holes. This is from air finding a pathway through in the drainage gravel and weeping tile below the slabs and through sump pump covers.
Radon
New research from Health Canada has lowered the acceptable limits of Radon exposure. Recent sampling across Alberta has shown unacceptably high levels in ALL parts of the province. Radon is a natural occurring carcinogenic soil gas that occurs throughout the province. The Environmental Protection Agency in the US lists long term radon exposure as the 2nd leading cause of lung cancer in the States, and number one cause among non-smokers. We would expect similar findings in Canada, if not higher due to more common use of basements. To prevent radon, improve your airtightness and install a mitigation system, which normally entails a ventilation duct.
Ventilation
Air sealing your basement will improve overall comfort by keeping the cold air from settling in the basement, reduce energy costs due to increase heat loss and improve indoor air quality. However, better air tightness must always be tied good ventilation. The walls and ceiling of a home (the “envelope”) can never be too tight, but many homes are under ventilated. To achieve this, we would recommend installing a Heat Recovery Ventilator (HRV) or Energy Recovery Ventilator (ERV). Both exchange heat when drawing fresh outdoor air and exhausting stale indoor air, with the difference that ERVs also exchange humidity.
Appliances
New Fridge: Getting rid of, or updating your fridge can make a noticeable difference in you power bill. Old fridges are notoriously inefficient. Look for ENERGY STAR labels and compare efficiency ratings.
Washer and Dryer: Clothes washers are large water users in typical homes often second only to irrigation or toilet use. ENERGY STAR washers use less water and energy if certified. As for driers, look for units that are ENERGY STAR and with “Auto Dry” sensing so that clothes are less likely to be over dried, wasting energy.
- Best in class appliances can be found at their web site: ENERGY STAR Most Efficient
- All ENERGY STAR labeled appliances can be found at: ENERGY STAR Product Finder
Resiliency Measures
Carefully assess how your home and property responded to water and take appropriate actions. Here are a few tips:
- Sanitary sewer lines can be retrofitted with back flow preventers, now mandatory on many new homes.
- Improve surface water drainage away from home ensuring ground is higher next to homes foundation and slopes away on all sides.
- When rebuilding decks and exterior stairs ensure that wood to concrete connections are separated using metal flashings to improve longevity of the wood.
- Using hard surface floorings in a home improves indoor air quality by not trapping dust and contaminates.
- Use non-paper based drywall for first 4' or more of basement. This type of drywall will better to be able to withstand water damage and if combined with non-absorbent insulation will likely not require removal if it floods.
- Properly installed, drained sump pump system.
- Consider a solar back up power system with small amount of battery storage. Generating free power in the good times and running the homes critical systems in troubled times.
New Alberta Building Code requirements are in place in flood prone areas, talk to your local building officials for detailed information.
Sustainability
Many times the added cost to “Go Green” over standard practices is minimal and in most cases should not run more that 10%. Consumers have to be aware of green washing of many products, if a product does not meet the thorough and stringent requirements of LEED, you should be suspicious. Here are a few items to look for to create a more sustainable home:
Low VOC
Look for new products that are Low VOC, especially paints, sealants and varnishes. They can prevent problems such as allergies, and long term exposure to toxic chemicals.
Recycled content
Make sure to prefer post-consumer recycled content rather than simple factory offcuts and similar which are considered pre-consumer recycled content.
FSC (Forest Stewardship Council) Wood:
Choosing FSC-certified products means choosing products that come from a sustainable and responsible source. For more information visit https://ca.fsc.org/index.htm
Local
Whenever possible, choose local products. Locally produced products have less distance to travel, so they have a lower embodied energy.
Choosing your team
Many trades may inflate prices when requests are made for unfamiliar products or techniques, so look for experience on certified green building projects when looking for contractors. Here are some rough example costs:
- Typical Basement Reno:………………$30 000–50 000+
- Improved Insulation:…………………..Add $2000–4000
- ENERGY STAR Appliances:……………Add $0–500 each
- Improved Hot Water Tank:…………….Add $300–1000
- Improved Furnace:…………………….Add $300–2000
- Improved Air Tightness:……………….Add $0–500
Reconstruction
If your home requires a gut renovation (walls opened up in all or most areas) there are even more opportunities to re-build better. The new construction will have to follow new building code requirements. Overall, the same recommendations apply, better insulation, better air tightness, and better ventilation will ensure that your new home will exceed current building practices and look ahead to a sustainable future for all Albertans.
In a full renovation, your home would be eligible for enrolment in the LEED Canada for Homes program, providing you with a clear guide to rebuilding a sustainable, durable, energy efficient home. A LEED for Homes Provider will be your point of contact, reference and guide through the program. Adding LEED certification can cost as little as $2,000 in fees and inspections, with most often less than 10% added to the cost of construction. LEED has certified over 200 homes in Alberta and over 3000 in Canada. LEED is enforced and used by builders, municipalities and governments across Canada and recognized leader in sustainable building.
Let us know how are you approaching your renovations, or if you are still suspicious if a 10% increase in cost is all you need to get a more sustainable home.
