The PEX tubing for the hydronic heat being installed. Next week, the concrete floor will be poured, and this tubing will be embedded inside

In our current two-story townhouse, we always struggled with balancing the internal temperature throughout the house.  During the winter we were always trying to close off the forced air vents in the upstairs bedrooms (as we all like to sleep in cool bedrooms without super heated desert dry air blowing down on us).  Short of taping the ducts closed, however, we were never very successful at keeping the hot air from blowing into the bedrooms, so we hired some HVAC contractors and had them split the heating and cooling into two separate upstairs and a downstairs zones with separate thermostats and separate ducting.  What a wonderful difference this made!  After a few years of living with the two zones, we have discovered that not only do we never turn the heat on upstairs during any season, but that even if we only heat the downstairs, we often *still* have the bedroom windows open to keep them cool enough to sleep at night.  Yes, warm air rises.

I suppose if we were smart, we’d put the bedrooms all downstairs, and the living spaces upstairs, but maybe in the next house we build (ha ha).

“Warmly Yours” electric heating mat being embedded in Natalie’s bathroom floor

For this house, we decided that given the large central stairwell, and the extremely open upstairs floorplan, we would only put hydronic heat in the downstairs concrete floors, and count on the HRV (Heat Recovery Ventilation) system to keep the air circulated during the winter when it is cold enough to shut the house up tight.

The only heating upstairs we are putting in are electric warming mats embedded underneath the stone bathroom floors. Because the bathrooms are the farthest from the stairwell, and also we tend to like the bathroom a bit warmer than the bedrooms, we decided we should heat these.  (Not to mention that cold stone floors are quite unpleasant under bare feet! )

The energy we will use for two heated floor bathrooms if we heat the floors for two hours in the morning, and two hours at night is about 1 kWh per day.  We have the same type of floor warmer in our current bathroom on a similar schedule with a programmable thermostat and we have found that we use it from October through May (8 months of the year – interestingly more of the year than we use the central heat).  Assuming we do the same thing with our two upstairs bathrooms in the new house, this puts the bathroom floor heating in the 250 kWh per year range which is about 1/100th of my estimate of the space heating requirements of the old house, and about 1/15th of my (hopefully) generous estimate of what the space heating requirements will be for the new house.

The view above the stairwell where you can see five paint colors!

As we embarked on painting, I was rapidly running out of time to research what we needed to do with the paint, so this is a bit quick and dirty.  I know that low or no VOC (Volatile Organic Compounds) paint gets you LEED points and “Green Points” and your Boy Scout merit badge for saving the earth, but NOWHERE in all of the info about low and no VOC paints is there any kind of *quantitative* data about how much you don’t emit if you “go low VOC”.   There are many of the same kind of wishy washy relative “this is better than that” statements to be found on the web and in those lazy journalism eco-articles, that made me go beserk about countertops.  Of course the marketing materials of these paint companies assure me that I am saving the world by buying their product, but, can you blame me for being suspicious?  I couldn’t find anything that would let me calculate how much I would save by using low VOC, in numbers that meant anything to me and could give me an idea of relative values.

So I did a back of the envelope calc, and decided to buy zero VOC paints, but this is not as rigorous as I would like it to be, and if there is anyone out there who has done a real analysis of this, I’d love it if you could drop me a note.

First some definitions:

“No VOC” = 5 grams VOC/Liter of paint

“Low VOC” = 20-200 grams VOC/Liter (most eggshell and flat paints that claim “Low VOC” on the label are in the 25 g/L range, but glossy paints tend to be up towards 150 g/L)

“Regular”  (i.e. “interior latex paint”) = 200 grams+/L

NOTE: this is for the base only, and some companies play fast and loose with their claims as the colorants can add significantly to the VOCs in the paint, but these are reasonably good ranges.

Some of the 27 odd gallons of paint we used

Many of the benefits that people ascribe to the low and no VOC paints have to do with indoor air quality, but since 99.9% of the VOCs are gone after the first two weeks of drying – it seems to me that this aspect of the low/no VOC debate only really matters if you are painting a house you are going to be living in at the time of painting, since after the paints are fully dry, a properly vented house would have no discernible difference in air quality.  Given that we aren’t living in the house yet, I discounted the indoor air quality aspect (since painting with the stuff, however, next time I am painting a house that I am living in at the time, I am DEFINITELY using “no VOC” paints, as anecdotally, it made a huge difference in the livability of the space during the two week drying time)

But if I am simply interested in figuring out my effect on the environment, if I use about 100 liters of paint (~27 gallons) of paint inside the house (including primer and extra coats), then using zero VOC paint in the house vs. “regular” saves at least 200g/L*100L = 20 kg of VOCs

From the EPA “Automobile Emissions: An Overview.” Fact Sheet OMS-5. August 1994, my typical commute of two “cold start” car trips a day and my car sitting around evaporating fuel, I produce about 24g of VOC per day from my car (4 g/day from evaporation only if I just let it sit and don’t use it).   So painting the house with “zero VOC” paint is the equivalent of over 800 days of a 1997 automobile’s VOC emissions. (OK, I have a newer car that that, and my running and evaporative emissions are probably much lower, but even if it is half that, I am saving over a year of car emissions)

That was enough for me to make the decision.  Without looking into it further, we went zero VOC, and bought the Benjamin Moore “Natura” paints.  And they were remarkably un-stinky as we painted.

Should a “green” house be painted green?

Seeing four spaces at once at the top of the stairs

In our current townhouse, we don’t have much white, and no two rooms are the same color.  Our living room is orange, bedroom green, the office a steely blue, Nat’s room is bright purple and “rocket red”, her bathroom an undersea mural…

looking out from the office

The new house has a very open floor plan, which is wonderful for airflow and light, but it means that the colors we choose for each room will often be visible from other rooms, and the combinations you see will be different depending on where you are.  This called for some careful planning!

Natalie tries out "tangerine" on her North wall

We knew we wanted bold colors, but at this stage in building, we are definitely suffering from “decision fatigue”, and we wanted to find someone who could help us with the process.  At the excellent recommendation of a friend, we found Jana Geller (listed in the contacts link) to help us with both color and stone choices, and have been playing with bold colors that mix and complement from the many different angles that you can see in the house.

Painting this week, then on to flooring and finish work – exciting!