insulation

---

The performance of the insulation of a home has as much to do with design, materials used  and installation as it does with the R- value. R-value is important. But how and where we put it makes all the difference. 

In a slab on grade home, much of the heat can be lost at the edges of the slab.  If it is Zero  degrees outside and you are heating your slab to be 70 degrees, that is a huge difference in temperature between inside and outside. Without a significant thermal break to insulate your slab and keep that heat in, through conduction, the earth will suck tremendous amounts of energy from your home. With good insulation around the outside of the foundation, less is required underneath as the earth’s natural temp under the home will stay between 50-60 degrees. 

In the walls of a home, framing lumber can act as a thermal bridge, allowing conduction of heat energy to pass through the wall. It is not a good conductor of energy, but it will act as a bit of a thermal bridge. It is a good idea to either put a layer of exterior insulation, or provide another kind of thermal break, such as double-stud walls.

Ceiling insulation is incredibly important. Meticulous air-sealing at the ceiling is done at all electrical and and any other penetrations. We take the time to seal up everything so water vapor and heat energy do not move where they shouldn’t. 

The insulation from the bottom of the slab, through the foundation, up the walls and overhead, combined with tight air-sealing details create an amazing, high performance home that will bring years of comfort and very low energy bills. We feel it is better to spend the money on the front end. We know that energy-efficiency doesn't necessarily make people willing to spend more money on a home. But energy prices will only rise over time. A cheaper home without this level of energy detailing will not only be less comfortable to live in , but will cost dramatically more to occupy.

Rockwool is a renewable material with many benefits. It has a high R-value per inch, it is hygrophobic (repels water), breathes well, allows water vapor to pass through it and it is extremely fire resistant. You can hold a blowtorch to it and it will not burn. It is non toxic and does not off-gass. It is very stable, does not settle or compress and will do its job over the lifetime of the building. It is comprised of heated and spun rock and will not provide any food for mold growth. It will not provide food or shelter for termites and pests.

Dense-packed cellulose is a great insulator. It is essentially newspaper, but is actually more fire-resistant than the usual fiberglass bats. Because it is loose, you can pack it in to places and ensure that there are no holes in your insulation game. And we like that it is closer to nature than foam or fiberglass.

Spray foam has its applications and places in construction. Some of the air sealing details in this home require small amounts of foam and it does a great job. But there are down sides to using foam as insulation for an entire home. Spray foam requires the use of propellents that harm the atmosphere and contribute to global warming. Spray foam is polyurethane, a plastic. The world is drowning in toxic plastic. Someday all houses are torn down, what will become of all this construction related waste? We have to think of this when building. Spray foam off-gasses, do you want your entire home wrapped in it?We don’t think so. Also as time passes and houses with spray foam are re-assesed, less building science experts reccomend its use as a whole house option. Its promises of high R-value and air sealing are starting to fade. It has its place in certain situations, but for an entire home, healthier options are available.  

The windows matter. Aside from allowing us to gaze at the mountains, windows are also performing vital home functions. Each window, its placement, its functions and its coatings are carefully considered. We like using primarily fixes glass windows, with a few carefully chosen operable ones for fresh air. Casement windows and awnings make a better seal than sliders or double-hung windows. 

The coatings matter.  We spend more money on the coatings than most builders do. Each side of the house has a specific need for coatings. On the South, we use coatings to prevent radiant heat loss from the building to the outside, but the coatings allow full solar radiation to enter and warm the house. On the west and east, we block solar radiation from entering the building as well as an additional coating to prevent heat loss from radiation outwards.  The east and west Glazing on a home is important to consider.  

Many houses in the Baca have huge view windows, but look closely and you will see that year round, these windows are covered to block the sun, which defeats the purpose of a view window.  Either the coatings weren’t considered or the appropriate technology did not exist for these large view windows to provide views and protection from solar-overheating. Our east and west widows will provide for breathtaking views AND will contribute to the performance of the home.