Existing homes can be brought up to or near the same energy efficiency performance as high-performing new homes. How do we do this? For starters, the amount of insulation that will fit in a typical residential wall is more suitable for mild climates, like northern California. In Minnesota, using this amount of wall insulation is like standing outside in January in a windbreaker. You are going to have to burn a lot of calories to stay warm and you aren't likely to be comfortable. This is why our energy bills are so high. We need more insulation to be comfortable, stay healthy and expend less energy. To do this, we pull a parka over our windbreaker house. This will keep the house warmer in winter and cooler in summer. We will be more comfortable and spend less winter heating and summer air conditioning energy. We also want to manage air movement through our windbreaker and parka. Air carries moisture. We don't want that moisture condensing on interior home surfaces or inside our walls, roof and foundations. Uncontrolled temperatures and moisture are what cause condensation on windows, walls, foundations, attics and roofs, including roof melting and ice dams. Although homes are typically built of the same materials, each home is unique in how these materials are combined. Home walls, roof and basements / foundations vary in insulation type, thickness & continuity, moisture management (or not) material type & continuity, and window & door performance. Varieties of HVAC (heating, ventilation & air conditioning) systems, hot water heaters, appliances and the number of occupants also affect interior temperature and moisture conditions. We address all these as parts of a whole, a system, where each building component is considered and designed to operate as a team member in a whole system. Building science has evolved similar to automobiles, cell phones and computers. They operate at a higher performance levels with better living results. That is the goal, better living.
Remember, each home is different. We have many tools, many building construction methods, to address each building condition at walls, attic / roofs, foundations and windows & doors. Not designing with building science and these tools is why many home remodels or remedies create new problems.
Read our next blog to get under the hood on how some of this is done.
Mark Anderson, AIA, CPHC
For my day job, I'm an architect focused on green design. Not a bad gig! Caring for the planet is a theme throughout my life. This page is where I like to talk about how that love for the earth plays out – in architecture and in my life.