The foundation has made significant progress. The rough plumbing was put in. Then those trenches were covered back up. New trenches were dug for the interior footings. The forms for pouring the stem wall were completed. And now stem wall and interior footings have been poured. Note the cutouts in the stem wall where the doors are going to be, leaving room to add insulation below the doors (using purenit or equivalent).

The insulated foundation looks clean and simple on paper: 4 inches of insulation everywhere around the slab, making sure there’s no way for heat to escape from the concrete slab to either ground or stem wall without going through at least 4 inches of insulation. (That amount of insulation provides an R-value of about 20; 4 inches of concrete has an R-value of less than 1.) When I arrived to check on the work in progress, the reality was not quite as simple, and would definitely not insulate as required.

The slab was poured on Monday July 15, starting at 7 am. The whole operation went very smoothly. They were careful to push the insulation into place as the concrete was poured, to avoid the concrete flowing into cracks. Moving the house a few feet westward paid off: the ready mix truck could get through on the east side and deliver concrete from the back, eliminating the extra cost of pumping the concrete.

The wall panels need a base plate to stand on. The base plate goes around the perimeter of the house – the red ring in the following image: The base plate fulfills several functions: It moves the straw panels a few inches off the ground to protect them from any future water mishap. It’s firmly tied down to the concrete, and in turn gives a solid base to screw the panels into.

After a long trip from Lithuania, the EcoCocon wall panels finally arrived at the site. The panels consist of a load-bearing wood frame densely packed with straw (110 kg/m3, about 7 lb/ft3). The panels are light enough to be moved by two (strong) people. However, a mechanical loader helps a lot. EcoCocon recommends starting with a corner and building out from there. The panels have dowels to align them, and get screwed together, but not anchored in the base plate yet.

It’s amazing when you’ve been carrying a design around in your head for so long, and it finally gets realized. With the walls almost completed, I’m very happy to see the plans come to life. Here’s the last beam being placed in the front. The current state as seen from the hill. And here it is as seen when you’re coming up the street. A few panels are still missing.

Lots of progress in the last week. The walls are now complete; the last panel was a very tight fit. Interior walls Meanwhile, the interior walls are being built: first assembled on the floor, then raised to vertical. And the roof trusses have arrived. Airtight membrane The airtight membrane on the outside gets taped to the waterproof layer that went underneath the base plate. The membrane continues underneath the ring beam to be added on top of the walls, and then taped to the membrane underneath the roof, making the whole house as airtight as possible.

I was on a family trip to Norway and Portugal for two weeks. We got updates and handled some house questions while traveling, but it’s good to be back and see the progress with my own eyes. A lot has happened. Roof We have a roof! As the roof is at a low angle (4°), TPO works really well. We looked into a standing seam metal roof, but it would have been twice the cost, which was not worth it for a roof that’s mostly hidden.

Roof overhangs are an important component of the whole passive house strategy: keep the sun from hitting the facade during summer, let the sun help heat the house during winter. In the Passive House Planning Package (PHPP) spreadsheet, each window not only includes size and orientation, but also overhang depth and position. This allows the heat gains to be calculated accurately throughout the year. However, this only works if the value entered in the spreadsheet is correct.

Things are happening – significant progress this last month. First, they installed the glass in the huge windows in the living area. The view from the planned couch location remains amazing. Here you can see those windows in the context of the kitchen and living area. Doors to backyard and patio still need to be installed, but you can already feel that the temperature inside is more comfortable and even than in regular constructions.