Photos of our ICF

[jonrjen]

One of the nicest parts of an ICF house is, 5,000 square feet, Texas hot sun and summers and yet the highest electric bill last year was $238. Not bad!
Our old house was 5,000 square feet, conventional stick and brick construction and we could expect electric bills to be 3 to 3 1/2 times higher.

[Pat]

jonrjen, Good design. I am definitely in favor of whole house ventilation, especially with good tight construction. With a good ventilation system I don't think a house can be too tight.

If you are not using an ERV or HRV then building a super tight house compared to "a fairly tight house" doesn't have much if any payback as the cost of the extra tightness is wasted. A properly built "SUPER TIGHT" house requires engineered ventilation, such as you have or better, not accidental ventilation.

If I may make another pitch for ERV/HRV... since you recover much of the heating, cooling, and in the case of the ERV, also the dehumidification costs, whole house ventilation with an ERV or HRV is free or low cost. IF your whole house ventilation system has a limited number of exit ports (I have only one) and likewise the inlet air ports, then a retrofit ERV or HRV is really simple.

Reasonable use of the whole house ventilation system exhausts a significant volume of conditioned air. Make up air has to be conditioned at some real cost. An advantage of the ERV or HRV is a good reducton in the cost of conditioning the replacement/make up air.

I suspect some consideration was given in your whole house ventilation system to exhausting "TOO MUCH" air and hence the clever use of timers. Your system can place a significant load on the heating and cooling. If run quite a bit in hot humid weather it might seriously impact the humidity level/comfort in the house.

I too face a similar problem. I wanted a powerful range hood. I joked about the design criteria surpassing just making your tie flutter but to also endanger small children and pets. I wanted to be able to exhaust up to about 700 CFM. This would have tossed out a significant quantity of conditioned air, sucked a vacuum on the house, and made for poor indoor air quallity as the make up air would not be conditioned. I ended up designing a ballanced system with two blowers, one for exhaust and one for make up air with both conected to the hood I designed. The incoming air is directed through a linear nozzle about 3/4 inch wide by almost 4 ft wide across the front of the range hood. It is directed downward and makes an air curtain that separates the kitchen air from the volume of air over the range. This outside air is between the room air and the exhausted volume above the range so it is the first to be "sacrificed" rather than the conditioned air. The blowers are variable speed with the inlet air providing about 90% or so of the exhaust air. The speed controllers are connected such that you just have to twist one knob. For noise purposes the blowers are remoted. The inlet blower is above the front porch ceiling where it will not get any rain water and the exhaust blower is mounted on the roof.

I have installed the hood and just a couple days ago the HVAC crew put in the blowers. I am anxious to get the controllers in hand, wired up, and giving the system a test. Right after the holidays I am hoping the electricians bring power to the ERV since there is no air delivery to the walk-in closets except when the ERV exhausts air from the back of the closets causing conditioned air to flow in to replace it. I still have just a little finish work to do in the closets.

Rather than timers I chose humidistats. A wall mounted humidistat just upstream of the doorless shower is a good example. It causes the ERV to run till the three exhaust ports in the bath room reduce the relative humidity below the adjustable set point. Relative humidity in the bath room is a fairly good indicator of its air quality. There is also no air delivery to the master bath (no cold drafts) except for the gentle drift of conditioned air from the bedroom to the bath. As the master suite is ICF exterior walls this gentle drift of air is enough to control the temp during the cooling season. During heating season the floors of the bath room as well as the floor of the shower and the shower walls are heated hydronically.

Yesterday was my wedding anniversary and what I gave my wife was a working toilet in the new house. I had to make the mounting bolts as the ones from my supplier were too short due to the floor tile. Now before everyone thinks me a total cheapskate cad... I also took her to dinner and a movie (Star Wars Episode III, Revenge of the Sith) Like they say, Sith happens! We went to a Mexican place about 1100 miles out of Cancun.


[img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img]

[RaT]

<font color="blue"> I had to make the mounting bolts as the ones from my supplier were too short due to the floor tile. </font color>

Pat, was the closet flange not flush with the tile?

[Pat]

RaT, No, not only was it not flush wilth the tile it wasn't even flush with the top of the slab. I am using two wax rings. I will have to go back and do an R&amp;R on the one I installed with modified carriage bolts as even with galvanized, in this service they may not last well and I will replace them with brass now that I have bought some longer ones.

Funny thing... the shorter bolts are 5/16 and the longer ones are 1/4... This is true from more than one supplier. Yet another little mystery of life.

[img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img]