Showing posts with label House renovation. Show all posts
Showing posts with label House renovation. Show all posts

Sunday, April 13, 2014

Self Sufficiency, Five Years In - audio slideshow

In spring 2011, I gave a presentation three times on the progress, successes, failures, and lessons from five years of working towards self sufficiency with my ex-partner at our house in Portland. I advertised the event with this blurb:

In March of 2006, Tulsi and Norris purchased a small house on a .2 acre lot, and used permaculture principles to design their food forest, sun garden, and house renovation. They aimed to create a low-maintenance, truly sustainable habitat for 2-4 people plus wildlife, providing from the property all necessary food, heating & cooking fuel, water, and waste treatment. Join us for a reality check on what's worked and what hasn't, what seems theoretically possible for the future, and what all this means to the oxymoronic goal of a sustainable city.

I've finally synced up an audio recording I made of my presentation with the slide images, to make a sort-of movie. You can view the Self Sufficiency, Five Years In slideshow online (may require reasonably fast internet connection) or download a 36MB zip file for offline viewing. (Extract to anywhere on your hard drive, then open the included index.html file in your web browser.)

I've also created a video, which requires more bandwidth: Self Sufficiency, Five Years In on YouTube. (You can download the 166MB WMV movie file or watch it below)

Or you can download a 6 MB PDF of the slideshow without audio.

Friday, January 27, 2012

House Layout, Features, & Future Projects

Design Goals

Before embarking on our house project, we designed the final layout of rooms with a few criteria in mind:

  • Active living space at the south end of the house, to utilize the light & warmth from the sun.
  • Heat the entire house via passive solar with back-up wood stove.
  • Bedrooms at the north end of the house where the reduced light and cooler temperatures don't matter as much.
  • Natural daylighting in all rooms.
  • Add significant storage area for food, preferably unheated space (canned goods, fresh produce, roots, etc)
  • Integrate airlocks/mudrooms to reduce heat loss in winter and heat gain in summer, as well as contain dirt & wet clothes.


Goal Implementation

We built the sunspace at the south end of the house as one large room, suitable for a wide variety of active living uses - living room, dining room, party room, play room, study/office, etc. We "planted" our bath tubs to the south of the sunspace for extra heat & light gain in the winter. We planted a black walnut to the SW of the house, and built a grape trellis south of the sunspace for seasonal shade.

We installed an EPA certified wood stove facing the kitchen for radiant heat gain and comfort from the cheery glow. It heats the sunspace quickly. The sunspace sits 2' below the rest of the house, creating a natural convective loop of heat rising from the sunspace into the rest of the house, for fairly rapid heat distribution.

We added east windows looking onto the ecoroofs, to allow morning light into the NE bedroom, the pantry, and the sunspace. We added a wavy glass privacy window between the bathroom and the sunspace, since the bathroom had no natural light. The sunspace allows a lot of light into the kitchen and the SW bedroom (which also has a west window.)

We created a pantry with a 2' path down the middle and shelves lining the walls for efficient storage of lots of goods.

We didn't build the airlocks, but we left room to add them if desired: one in the sunspace around the back door, and one on the current front porch, enclosing the upper portion of the deck.

Other Features

The front porch makes a wonderful hang-out area in the summer, opening to the front garden to the north. Walls block the sun to the east, west, and south, and the ecoroof limits heat gain from above.

We made it easy to add a third bedroom (or office space) by constructing a single partition wall to turn the northwest portion of the house into a large closed off room.

We installed a sliding glass door between the sunspace and the kitchen, and of course the southwest bedroom has a closing door, so it's easy to isolate the sunspace for cozy temperatures in the winter without needing to heat the entire house.

We built nice big stairs from the kitchen to the sunspace, very inviting for people to sit and gather on.

When we lifted the original house and put a perimeter foundation under it, we wound up with three holes in the foundation wall so the I-beams could lower the house onto the wall. We discovered that in the summer, opening those holes creates a natural air conditioner as cool air from the crawl space flows into the sunspace.

Future Projects

If we were staying in this house, we would:

Add insulating curtains to the sunspace window wall. (And figure out insulation for the other windows in the house.)

Replace the wood stove with a rocket stove, for dramatic efficiency improvements in heating and cooking.

Remove the natural gas forced air furnace and associated ductwork in the attic, since we never use it and it wastes a lot of space (usable room space in the southwest bedroom, and insulation space in the attic).

Install the five hot water solar panels we bought, using them to heat domestic water and to run the excess heat through the radiant tubing under the original house.

Build a greenhouse on the south side of the sunspace, enclosing the bath tubs with the grapes growing on top. Move the chickens to sleep in the greenhouse.

Plant more plants on the west wall or west side of the house to create more summer shade while utilizing that growing space (without interfering with its current use as hang-out party space.) Perhaps plant akebia or scarlet runner beans against the house, and/or trees further out trained to high-branching trunks for easy human passage underneath.

Build a cold cupboard to tap into the cool crawlspace air and pull it up through a small pantry area to keep perishable foods a little cooler in the summer.

Site Plan

Here's the house in relation to the property boundaries, showing setbacks for addition of an Accessory Dwelling Unit:

Wednesday, November 16, 2011

House insulation & initial results

As part of our house renovation over the last two and a half years, we've added huge amounts of insulation, getting the whole house to an average of about R-30. Here's a rundown of what we did.

Materials

  • Fiberglass - about R-3.5 per inch. Not the highest R-value, and kind of nasty to work with, but cheap. We got lots for free from craigslist, and lots for nominal cost from the Rebuilding Center, a local salvage/resale place. We used this in spots where we had ample room to stuff insulation and thus could use this cheaper product.
  • Loose-fill (cellulose and rock wool) - R3 to 3.5 per inch. Our attic had a thin (~2" on average) layer of cellulose, and we got a few more bags for free from craigslist.
  • Polyisocyanurate rigid foam board - R6.5 per inch. Expensive (even used, at about $10-$15 for a 2" x 4'x8' sheet), but highest possible R-value per inch. We used this where existing framing limited our available space for insulation: original house walls and the floor joists. Most of this had reflective foil faces on both sides.
  • XPS rigid foam board (pink and blue board) - R5 per inch. Somewhat pricey. We got some used, but bought most of it new. Resistant to water uptake, and with high compressive strength, so we used this under the concrete slab in the new sunspace. Also used it in some walls where we ran out of appropriately thick polyisocyanurate.
  • Reflective "bubble wrap", similar to the commercial "Reflectix." Petsmart receives their tropical fish in 2' x3' double-layered "envelopes" of this stuff; Tulsey arranged for us to pick up big stacks every 2 or 3 weeks, saving them from the dump. We used these as air and vapor barriers, and the bubble wrap probably adds about R-1, and they may have significant value in reducing radiant heat loss. (The last claim is somewhat controversial.) We did have to buy the shiny tape to seal adjacent strips together.

Application

Walls

Approximate R-value: 20
In the original portion of the house, we gutted two bedrooms with no wall insulation and filled them with 3" of polyisocyanurate (or in a few places, 2" of polyiso and 1" of XPS just because we ran out of polyiso materials to get us to 3".) We had to cut the insulation to size, which was not difficult, but was somewhat tedious. Next we furred out the walls with some old lathe, to make the total cavity depth a full 4". We built the east and west sunspace walls to be 8" wide, with 2 rows of 2x4 studs with 1" offset between the rows with scraps of rigid board to reduce thermal bridging. The south wall mostly has windows, so we built it with 2x6 studs. We filled all the sunspace walls with fiberglass insulation.
With all the walls, once we had the insulation in place, we ran the bubble wrap insulation over the interior face of the studs, then into the wall cavity until it hit the fiberglass or rigid insulation, then along the face of that insulation until the next stud. The goal was to create a 3/4 to 1" air gap between the shiny bubble wrap and the sheetrock attached to the studs. This air gap is critical for the reflective nature of the bubble wrap to reduce radiant heat loss.

Ceiling

Approximate R-value: 40. The bubble wrap acts solely as an air & vapor barrier, not as a reflective barrier.

Original House

We redid the ceiling in about half of the original house, so in those rooms I attached a layer of bubble wrap under the ceiling joists (on the room side). In the rest of the areas I nestled the bubble wrap into the joist cavities from above (similar to the application to the walls), first removing the thin layer of existing loose-fill cellulose. I'm using our loose fill to fill the 2x4 joist cavities, then laying fiberglass bats perpindicular to the joists to a depth of 6-10". (I haven't finished all the attic insulation yet--I'm about halfway done.)

In the funny little pop-out of our NE bedroom, there was no way to access the attic space after sealing it up from below. So I stuffed pink XPS between the joists to create a supportive "platform" on top of which I could put fiberglass and loose fill before applying the usual bubble wrap to the bottoms of the joists.

Sunspace

We built the sunspace ceiling with 2x12 joists, in part to support the ecoroof load. We also built a 2x4 drop ceiling under that, so we were able to place about 13" total of fiberglass insulation. We finished with a layer of the bubble wrap insulation attached to the bottom of the drop ceiling joists before attaching the sheetrock.

Floor

Approximate R-value: 30.

Original house

Under the original house, we had no insulation to begin with. About 60% of this area had 2x6 joists, the rest 2x8. With the help of friends, I installed 3/4" PEX tubing under the living areas, which takes up about 1" and needs another 1" airgap between it and the reflective surface of the polyisocyanurate below. That left 3.5" and 5.5" available in the 2x6 and 2x6 joist cavities; I stuffed these with 4" and 6" of polyiso (with 1/2" hanging below the joist bottoms.) I finished off with bubble wrap stapled to the bottoms of the joists.

Sunspace

Going with the design of our passive solar consultants (Urban Sun), we used 2" of XPS (R-10 total) under the concrete slab, and against the interior face of the stem wall. The low R-value is a little deceptive, since it's OK to use the ground itself for some heat storage in the interior of the slab. Only the outside edges will lose much heat.

Crawlspace

I placed 2" of polyiso against the foundation wall butting into the sunspace, to reduce the heat loss from the sunspace into the crawlspace. Around the rest of the walls, we glued the bubble wrap for a little bit of R-value and hopefully some help from the radiant barrier.

Initial Results

Today marks the first time this year we've felt the need to make a fire to heat the house! We've definitely made it way later into the cold season than ever before. Some notes on our parameters:
  • We've been comfortable with the house ranging from 55F as a worst-case overnight low up to 61 or 62 or sunny days, generally in the 57-59 range during the day. Yesterday we were stuck at 55 all day long, and overnight dropped to 51, so we finally broke down and made the fire today.
  • We've been cooking and baking a fair amount on our gas stove, which adds a lot of heat to the house.
  • We've been taking hot showers every 3 days or so, which adds a lot of heat to the house.
  • Before today, we had made 6 fires, but hadn't really needed any of them for our own heating comfort. We primarily made them for open houses and house showings as we try to sell our house.