Build Your Home Ideas

ICF's For those of you who don't really know - ICF's are Insulated Concrete Forms. Basically they are foam legos (4 feet long, 16" high and thickness varies depending on how thick you need the concrete to be). The foam blocks have an open core between the inner and outer layer that is filled with rebar and concrete to give you your structure. Until we started building I thought all brands were essentially the same. Maybe the foam was thicker on some, but never thought they truly were different. We researched Logix ICF  and  AMVIC ICF's . Both had some pro's and cons. Logix has a higher R-value (R-22.5) and a more defined "web" to screw into, but the blocks need proper orientation for proper assembly (ie. Right hand and Left Hand Corners). AMVIC's blocks are universal - they can be used upside down and backwards to reduce waste. The R-value is slightly lower with the AMVIC (R-20), but we have the flexibility to increase the R-value of the basement ...

Capillary Break So we are under construction! The foundation has been dug,  The footers have been formed and poured. Now we are ready to start laying the ICF blocks... Right NOT SO FAST!         If we get too far ahead of ourselves we will miss a fairly important step. The capillary break is installed between the footer and the foundation wall. Concrete has amazing capillary action potential. Remember in science class in 3rd grade when the teacher added food coloring to water and put celery into the glass and we all watched the water travel up the celery. That is capillary action.          Why is capillary action bad? When you waterproof the outside of your foundation, water that is wicked into your foundation wall needs a place to go. It can't go out (though the water proofing) It must go in (into your basement). I will be insulating my basement walls beyond the standard ICF's, so I need to keep the insulation dry.      ...

Air Source Heat Pumps We have established that Passive Houses are air tight, super insulated and properly ventilated. Air source heat pumps are what we will be using to supplement the cooling and heating needs during the summer and winter months. An Air Source Heat Pump is both an air conditioner and a heater. In Cooling Mode Starting at the compressor: 1) Refrigerant is compressed causing the pressure to increase and turn the cold vapor into hot vapor. 2) The hot vapor enters the outdoor coil and is cooled by the outdoor air. This causes the hot vapor to change phases into a hot liquid (still under a lot of pressure). 3) The hot pressurized refrigerant enters the expansion valve where the  pressure is relieved and the temperature of the refrigerant drops (A LOT) 4) The cold liquid refrigerant enters the indoor coil and is heated up by the indoor air (cooling the indoor air in the process). This causes the cold liquid refrigerant to change phases into a cold vapor. 5) The cold vapo...

Whole House Ventilation I think the biggest question / complaint I hear from builders today is - Why do I need to make a house this tight, then add a fan to bring in fresh air? If I made it leakier I could save the homeowner some money. While to a certain extent they are right. They can sell you a less expensive, leakier house that is missing any kind of forced ventilation for the house. After all, your parents house never needed ventilation, their parents never needed ventilation, why do we need it? The fact is, for our climate in Rochester, NY, it is more efficient in the winter to run a 45 watt machine that recovers 90% of the heat, than to heat up all of the 10 degree air leaking into the house with your furnace, plus your furnace fan. The air leaking into your house is much drier (lower relative humidity) than the air inside your house. This means you either increase the thermostat temperature or add humidity to the air with a humidifier. Also in order for air to be coming into th...

On my last post I touched on the mold potential. I could probably do an entire post on Mold - but I am not a doctor, nor am I a certified mold specialist. I know it's bad, you know it's bad and we'll leave it at that. In this post I will be talking about the general health benefits that come standard with a Passive House. Some of the more common health problems that can be attributed too poor indoor air quality include:   allergies head aches asthma sleep problems Conditions which impact your indoor air quality: Mold High Relative Humidity Low Relative Humidity House is too leaky House is too tight High CO / CO2 levels Little Kids - I guess passive house can't fix that one (6 out of 7 isn't bad) Current methods used to manage the "symptoms" resulting from these underlying issues: Air purifiers Electrostatic furnace filters Dehumidifiers in the summer Humidifiers in the winter High powered exhaust fans Open windows -  which can bring in dust pollen and othe...

Thermal Bridges Forgive me for this post, I have been thinking about how I wanted to say this without sounding too technical. I'm going to try to simplify this a little bit.  A thermal bridge is any location in a building where conduction of heat can travel from inside to outside easily.                      An Infrared scan will help visualize these bridges. This is NOT an X-Ray. The infrared camera only measures surface temperatures. This is a thermal image of a poorly installed window. So what you are seeing are the yellow/white colors are warm temperatures and the blue and black colors are cold temperatures. As you can see, there is a substantial thermal bridge around the window opening allowing the cold temperatures outside to come in. In this case the efficiency of the window doesn't matter due to the poor quality installation. There is a temperature difference of over 12 degrees inside the box. This spot will feel cold a...