Sunday, December 13, 2009

Zone 2- the hydronic wall.

Winter arrived hard and fast, bringing the issue of heat to the forefront. The in-slab hydronic system is working fabulously on the main floor, but the hayloft is usually 5-10 degrees cooler and in need of supplemental heat. Since our future plans call for solar-thermal hydronic heating, I want our system to be able to run at the lowest possible temperatures. That said, I opted for a 'hydronic wall' in the hayloft, instead of underfloor heating that requires somewhat higher fluid temps. To get started, I framed in a partition wall to divide the hayloft into two semi-private bedrooms (we decided not to extend the wall all the way up to keep the architecture of the high arched ceiling visible).
Then I built a "hydronic sandwich" using aluminum heat transfer plates between 'sleepers' of 3/4" foil-faced isocyanurate insulation.
With Lisa's help, we routed 1/2" pex tubing in a serpentine pattern through the wall, across the doorway framing, through the smaller side wall, then back to the starting point...then we repeated it in the second bedroom with a separate run of pex...whew!
Here is a closeup of the assembly:
Finally, ready for drywall, which is screwed into the studs being VERY CAREFUL not to puncture the tubing runs.... The aluminum plates help conduct the heat out of the pex tubing and into the drywall surface. The insulation 'sleepers' act as spacers between the drywall and studs, and help direct the heat out outward to the room. The drywall surface readily conducts the heat and radiates it outward to the room. By using this method rather than the more tradition underfloor hydronic installation, more BTUs can be delivered to the room at lower water temps...and it was a much easier and less expensive method in this case. The obvious downside to this method is the risk of puncturing the tubing with fasteners. I took a lot of pictures of the assembly and documented the pex locations so if we ever need to hang a picture on the wall, I'll know where not to pound a nail!

Wednesday, December 09, 2009

Night lights

The lack of light pollution is generally welcomed in our rural setting, except when trying to walk around the yard in the middle of the night. Without moonlight (or a flashlight), it is black. Some landscape lighting was in order, so I dabbled with a couple versions of solar lights during the summer. They were all dismal in performance, providing little more than a flicker for a few hours after dusk. What we need is reliable pathway lighting strong enough to get our guests from building to building without wandering into the woods or falling into random barn foundations (which happen to be located smack dab in the middle of our yard). Fortunately I found a low-voltage lighting kit on clearance (80% off!), which had everything we needed for the job. With winter almost here, I scrambled to build some mounting posts that would elevate the lights above the snow cover we're about to get. I built a dozen posts from some cedar barn timbers, boring holes in the top for the lights to press in to: I set them up along the path from the house to the barn, and piled field stone around each post to hold them in place. This started out as a temporary fix to get us safely through the winter, but we think they look good enough to be permanent.
The light kit came with a programmable timer and 20W halogen lights, which meant our 11 lights were putting out 220 watts for several hours every night. That's crazy! I replaced them all with 2W LED lights, which are working just as well and cut the power consumption by 90%.

December Salad.

One of my gardening goals this year was to pick a fresh salad out of the yard in December, and we barely made it! I planted a fall crop of carrots, chard, mustard greens, spinach and lettuce in September- a little later than I should've, but most of it grew to an edible form. Protected by the cold frames covering a raised bed garden, they survived the frosty weather into the winter. Last week, we enjoyed our last fresh salad of the year- a variety of greens, radish, carrot and tomato (picked green in september and ripened in our basement). Then the true Minnesota cold moved in and took the rest- here is the remaining lettuce breathing its last breath. Next season I hope to pipe solar-heated water under the beds to extend the season a little further...