Sensors in the house envelope
Hi,
We are designing our superinsulated Pretty Good House inspired dwelling. It will be constructed during the summer, 2015, in west central Wisconsin. I am willing to place some instrumentation in the envelope (like temp and humidity sensors) during the build so the house performance can be monitored afterwards.
I’m asking for suggestions for what sensors to place where to get good data. What would you like to see monitored? I am interested in heat flow through the slab and basement walls as well as temp/humidity profile in the above ground walls, but I’m open to any suggestions.
Some basic house info. Near Minneapolis. One story with full basement. Three bedrooms, two baths. Full insulated roof (vented cathedral ceiling). Larsen trusses with mineral wool batts above ground. Exterior insulation below ground. 10 – 20 – 40 – 60 insulation minimum. 32 ft x 60 ft. foundation. I am planning on having a third party do Manual J and blower door testing.
Thank you
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Replies
Karl, sounds like a PGH indeed! I hope to build something similar in northern Minnesota in 2016. I am pretty new to GBA, but haven't seen a lot on this subject, but I am interested, being an electrician by trade. I have done minimal research as of yet, but for myself, I am planning to install a PLC (programmable logic controller) in my home. Simply put, they are wired devices that accept inputs (temperature, level, %humidity, time, etc), and turn on outputs (HRV, heat, cooling, lights, etc) to react to the inputs based on your logic. Home control systems are a variety of PLC. In short, if you have wired all the inputs to your PLC in your utility room during the construction phase, you can use them a little or a lot later on. I also would be interested to hear from any folks that have already done something similar.
However, if you are just interested in inner wall temp/humidity,
http://www.omega.com/googlebase/product.html?pn=RH820U&gclid=CjwKEAiA_NmkBRCe3ubC1aWAtEcSJACxkkbqpMWsMND4axsSlgW9q2qgnw5N25FUhZsaLjaQC3PbPRoC7Ofw_wcB
Omega has a combo meter with the sensors together for $205. I suppose you could get extra sensors so you could have them in more than one place, and the meter could travel between them when you want to collect data. I believe Omega to be a pretty good company, but have no experience with this unit.
Karl,
There are quite a few paths you could take to get there from buying plug-n-play systems to hardcore do it all yourself builds. I plan to use many temp sensors and several temp/humidity combos all on 1-wire. Reading the info is the easy part, getting to a PLC like the Allen Bradley Micro (which has free programming software) is tricky but might be possible via modbus protocol through an Arduino board. Then the fun begins (control). Here are a few ideas:
http://www.ourcoolhouse.com/scada.htm
http://www.ourcoolhouse.com/links.htm
http://www.ibuttonlink.com/collections/1-wire-products
http://www.maximintegrated.com/en/products/comms/one-wire.html
http://www.hobby-boards.com/store/categories.php?category=Weather
http://www.weathertoys.net/weathertoys/main.html
http://playground.arduino.cc/Learning/OneWire
http://ab.rockwellautomation.com/Programmable-Controllers/Micro820
Karl,
It is instructive to install a humidity sensor to measure the humidity of the wall sheathing. The best location is toward the bottom of your north wall.
Chuck, very good information. One-wire looks interesting and affordable.
Great answers. Thanks all. I will check out all those links, Chuck and Steve.