If you are still not thinking about how much energy your new house will use and how much it will lose, then this is the time to start. It should be one of your top priorities – if for no other reason than your own pocketbook.
The energy used to heat and cool homes will continue to rise in price and, as we have seen lately, global politics can quickly and drastically affect your access to cheap energy.
I'll get to the part of the house plans in a minute, but first …
A little story
This is not the first energy crisis we have had. In 1970 – when I was a student studying green design – world events talked about the creation of the American energy crisis. It was an interesting time to study Architecture because the buildings we designed were obliged to respond to the environment – to use natural sources of energy as far as possible.
The homes we created used technology and inventive design to give them shape – we designed solar homes, earth-sheltered homes, homes with heat mass and other types in a wide variety of shapes and sizes. They collected heat from the sun and the earth and kept it inside for as long as possible. They blocked excessive solar radiation with deep overhangs and shading devices and were very attentive to the angle of the sun and the prevailing winds.
Sure they look a little weird (some are downright ugly), but we designed homes that were warm in the winter and cool in the summer and used almost no energy ,
A little more history
But then in the 1980s energy became cheap again and everyone forgot about low energy homes (see, I told you – just a little more history).
Where are we now
Fast forward to the twenty-first century and suddenly energy is back on page one. Again, homes respond to pressure to reduce energy consumption, but in a curiously different way – through envelope and mechanical technology ,
Technology for envelopes
The envelope of your home is its cover – the roof, the walls, the windows and the base. What protects the exterior is just that. There was a time when the heat flowed fairly freely through the envelope; the windows were one glass thick and the walls and roofs had little or no insulation.
Today, the assembly of walls and roofs can be many high technology. New types of insulation, sheathing and siding slow heat flow to creep. Infiltration barriers (Tyvek, Typar, for example) stop excessive water vapor migration and seal the outside more tightly than ever before. Houses can be sealed so tightly in fact, the retained moisture can accelerate the growth of mold (this is an object for another time).
The windows and doors have also passed light years beyond the old wooden frames, plastered with glass from the beginning of the twentieth century. Windows are now available with multiple windows closed together to create an insulating layer inside; often this "air space" is filled with inert argon gas – which has a higher resistance to heat transfer from the air.
The window frame is far better sealed and the installation methods are much improved. Even ordinary old glass is not what it used to be – now it's covered with a microscopic layer that allows sunlight but blocks UV rays and prevents heat from leaking.
Other high-tech wall technologies include ICF (Insulated Concrete Forms) and SIP (Structural Insulated Panels).
Another area of major change is mechanical technology, including systems for heating and cooling groundwater sources, active solar panels and custom water heaters.
Stoves, heat pumps, heat exchangers, boilers and air conditioners are more efficient, always working hard to extract every BTU of energy from the fuels they use. And sophisticated computer control systems control the heat distribution throughout the house.
Back to the house plans!
Envelope technology and mechanical technology are two good ways to make every house plan more energy efficient. High-tech energy management systems can be added to any house plan, and most plans can be easily modified to incorporate the latest envelope technology. Some home plan sites even sell versions of their plans with ICF wall details already included.
Take advantage of high-tech energy-saving technologies wherever you can. As energy costs increase, more sophisticated fuel economy systems will pay.
But envelopes and mechanical technology are not the only way to create a more energy efficient home. Back in the day we did it with old-fashioned good design – paying attention to the sun's orientation, the amount and location of the window, and the shape and size of the house. An architect or qualified home designer can help you choose and / or modify a home plan to better address your energy use issues.
So choose carefully – a good looking house is not necessarily energy efficient.