Summer was off to a bad start. June was cold with an average temperature of around 7C accompanied by a lot of cloud cover and drizzle. I have realized over the past 10 years that outdoor living spaces in Newfoundland are really limited. Our summers are short and you really don't have a whole lot of time to use it. For this reason, I planned on using the outdoor space quite differently than my previous property. I also wanted to make sure that my time in the garden had some payback. Given the state of our food security issues I decided that a good place to invest my time and effor would be creating a landscape that has some food security. As well, I wanted a low maintenance landscape that grows well in our environment, and is resilient to drought and pests.
My plan for landscaping was quite simple really: Go back 50 years and do what most Newfoundland families did. They grew root vegetables. Good cold climate varieties that are tuned to our short growing season are easily accessible and they can be stored for long periods of time under the right conditions. With the right plantings, you can get multiple crops out of the same plants. With this in mind, We decided to grow onions (160), turnip(120), carrot (300), beets (100), cabbage(20), parsnip(100), and lettuce(who knows!). We also planted some herbs that lend themselves well to drying for winter use. Potatoes are a staple here and luckily they are dead easy to grow. Photo 1 shows the back yard in its current state. A vegetable garden takes up the whole back yard!
With all the vegetables and about 180 potato plants creating long term storage was a necessity.
I designed and built an underground cellar which sits in a slope on the east side yard. It is basically a concrete bunker with a structural slab sitting on the top. The whole thing was tarred on the outside and a pond liner was draped over the top to help shed water. I installed some left over 4”eps foam on the top of the slab in fear that I wouldn’t be able to back fill the cellar with enough soil to be effective against frigid winter temperatures and the heat of summer. The thermal properties of various soil types is pretty complicated. This being said, there appears to be a consensus that the r value varies between .1 to 0.25 per inch. So adding 4” of foam is equivalent to adding many feet of earth. It doesn’t add thermal mass but it is much easier on your back than shovelling a couple of single axle loads of topsoil! We added about 2’ of earth on top of the cellar and I plan on seeding it with grass sometime soon. I still have to build some shelving but there should be no problems having this ready for winter (Photo 2).
During April and May, I finished several larger projects: I added a small deck for the back entrance and a veranda under the front overhang. The driveway is now paved and the front yard is now being landscaped. I am hoping to seed this week with timothy grass, white clover, and red clover. Things are shaping up nicely.
As for energy use, our usage for the month of June 11- July 11 was 651 kWh. Given that the average June temperature was 7 C, I felt that this was fairly respectable. The heating system ran about two days all together. With heating season over, I can safely assume that this is approximately the baseload of the building. I have installed a Nyle Geyser hot water heat pump that helps with some cooling and dehumidification while maintaining the temperature of the Logix24 boiler tank for hot water usage. I expect that energy usage in July should decrease due to the Nyle installation. I also have the HPWH ducted upstairs which helps move air around.
The interior temperature of the house has been fairly constant. At one point, the temperature inside the house was about 23.5 C which is below the temperature that Passive House considers to be an overheating event....There were a few days when the outside humidity was so high that it lead to increased humidity inside the house. Unfortunately, during those days, I had the ERV set on continuous ventilation and didn't realize it. This was a huge mistake. This made the building very stuffy because of all the humidity. Humidity levels at 80% lead to apparent temperatures of about 29 C or higher! Humidity plays a huge role in comfort. So I have been playing with night time flushing by actively opening windows during the night and closing them in the morning and it has been somewhat effective. Even though I don't mind opening and closing windows I can see how it wouldn't be convenient for most people. There was a bit of a learning curve to determine how much to open our windows. Our location is so windy that the wind can blow the screens out of the windows! It would be nice if the night purge was more automated. I find myself looking more at the weather forecast so I can time opening the windows with cool temperatures and low humidity, only to wake up and find it has rained and the air coming in the house is at 95%+ humidity. The smart mode on the ERV tries to save energy by limiting ventilation when the temperature outside gets too hot. During this time it recirculates air throughout the house. I have found that having the recirculate mode set to 100% of the motor capacity helps with moving some cool air around. Some HRVs have the ability to bypass the core to cool the home when exterior air is cooler. My ERV does not. This is one feature that I wish our unit had. However, ventilation CFMs are usually not high enough to cover the cooling loads required so the extra money spent on the fancy ERV with bypass may not have worked out anyways. For now. I'll stick to opening the windows! My experience so far is that when the air is cool and dry outside, you can condition the house during the night for the next day but it takes some preparatory work. With the windows open all night, its pretty cool in the morning and can feel somewhat damp. I close up the windows and turn on the dehumidifier for a couple of hours. This typically drops the humidity less than 60%. During the day when the house is unoccupied, the humidity remains fairly constant. Once we get home it slowly increases. After several hot days days and warm nights, its impossible to control the humidity. This being said the temperature is usually manageable. A mini-split would probably be a good solution to the humidity problem.
Hi David,
ReplyDeleteI recently found your blog and find your project fascinating. I am part of a co-housing group on facebook (Co-housing Newfoundland and Labrador) that was created by Wendy Reid Fairhurst. We are very interested in your project and the possibilities of passive housing. Would you be interested in joining the group or possibly contacting Wendy directly?
Thanks.
Boyd
sorry for the late reply! looks like this was from a few years ago so not sure if it went ahead or not.
DeleteHello David,
ReplyDeleteHappy Holidays. How is your new home performing? Hope all is well.
Dan
the house has performed great. I am pleased overall.
DeleteHow has your experience been this winter thus far?
ReplyDeleteGreat blog. Is it possible to retrofit a house along passive house lines in the province at the moment?
ReplyDeleteyes it is possible. Normally you would work with a passive house consultant to make this work.
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