Passive Solar Renovation

The other day we were driving home at about 5:30 – just after sunset – and could barely make out plumes of wood smoke exiting cowls on Heads Road and Cornfoot Street. The day had been sunny, but cool, as would be expected in July. Our curtains were still open, so we hurried along while remaining under 50 km/hr.

We parked, grabbed the bubs and groceries, and walked inside. Upon entering our old villa on Arawa Place, we were pleased to feel the warmth gifted us by the sun. The thermometer in the kitchen read 23 degrees Celsius.

By now, my wife is tired of hearing me say, “Wow, it’s so warm in here. I can’t believe all those houses had wood burners going.”

I chalk the difference up to legacy and sunlight.

 Before

 After

Unfortunately, Whanganui has been left with a legacy of thousands of homes built with seemingly no regard to the sun or even thermal comfort for that matter. Many of the dwellings I’ve audited during the last three months through Project HEAT share these characteristics: cold in winter and hot in summer.

Our home would have been the same before its passive solar renovation. As a matter of fact, we met a woman shortly after we bought the villa who told us, “I’ve been in that house before. I babysat there once. That’s the coldest house in New Zealand.”

While no longer the coldest home in the country, it is still far from the warmest. But on a sunny winter day, we find ourselves toasty warm inside long after dark, and with plenty of solar heated water – all free energy with no daily line charge!

The primary way we tapped into this free, abundant energy source required no specialist equipment and no specialist skills. As a matter of fact, the ‘solar collectors’ we used already exist in every home in the country: windows. The problem with most homes is that the windows are evenly distributed between the north, south, east and west.

On sunny winter days, only the northerly-facing windows have a positive energy balance. In other words, they gain more heat through sunlight energy during the day than they lose through radiation at night (if properly curtained, as you would). All of the other windows have negative energy balances even on the sunniest of winter days.

For us, the obvious solution was to ‘shift’ windows from southern exposure to northern exposure. While retaining roughly the same amount of total glazing, we were able to dramatically improve the solar gain of this old villa where – once upon a time – someone decided to put the toilet in the north corner.

 Before

After

Shifting the toilet to a more appropriate location was accompanied by opening up the north corner to create a bright, warm, cosy kitchen with French door access to abundant backyard vege gardens and an outdoor pizza oven. All of the work was done in accordance with the New Zealand Building Code, with special attention paid to weather-tightness and bracing.

At the same time, we insulated the ceilings as well as those walls that were opened up during the renovation. And finally, we added thermal mass inside of the building envelope to moderate and store solar thermal energy, but that, my friends, is a story for another day.

Update 3: The back half of the house

This is the third and final post in the Update Series, giving you a glimpse of our progress on the project over the past 8 months. The first post talked about the exterior of the house, the second about the front half of the interior, and this post will focus on the back half of the interior.

This part of the house, a lean-to added to the house around 1915-1920, was in a state of disrepair when we arrived. A previous owner, or several of them, had begun renovating the space. When we bought it, it had been divided into several small rooms on the north-eastern side and one larger room on the north-western side. We quickly made plans to swap this around to take advantage of the sun's free energy (and to block it out when we don't want it).


This is what the large room in the northwest looked like when we arrived. It had been used as a kitchen.

We constructed a wall (reusing the studwork from other walls we took down) to close off this room. It would be our new bathroom. We made sure to move the heavy cast-iron bath in before we put up the wall. (Every once in a while we go about things in the right order!)
We then removed the old kitchen cabinetry and brought in a toilet, vanity, washer and tub. Kiwi homes traditionally have a small toilet room separate from the bathing room. We opted against this, because we thought having one big room would allow us to use the space in more ways. We can now dry our clothes in here on damp days, and were able to position our heavy tub to catch the sun's rays from a northwest window, acting as thermal mass.
We then removed the window that faced southwest. This was a net energy gainer in the summer and a net energy loser in the winter. Quite the opposite of what we were aiming for.

And finally, this is the stage we are at now. We're fairly close to being done in this room (which is very exciting after living with only a camping shower since October). Just a few finishing details to get to before we have (finally!) a fully functional and beautiful bathroom!


Moving along the house, we get to the back door. Although, do you still call it a door when it is boarded up with iron so you can't get out, but still manages to let a huge amount of rain in. Let's call it our "back weather inlet". First step was to reframe the door and fix the damaged wall.
We then built the bathroom wall, creating a back entry-way that would help insulate our cozy house against harsh winds and cold weather in the winter. It would also be a handy place to store garden tools, boots, our solar cooker, and potentially a hot water heater.
But it turned out that our solar hot water cylinder lives on the roof, so our closet can now get used for storage. It's actually the only closet in the whole house. This picture is kind of confusing, but this is how the back entry way looks now. Our closet door is on the left and our two back doors (storm door and inner door) are shown under a home-made pelmet. Gum boots to the right and tools tucked in the corner to the left. We have yet to add a door to seal off this room, but when we do, I am hoping to find a glass one that will let the light into the hallway.

Alright, so finally we get to the new kitchen. As you can tell from the below pictures this was all studwork when we arrived.

It was tough to get a full shot because it was so narrow and dark, but this is a view moving down the length of the room, ending at the pièce de résistance.
In a show of manly strength and strength of stomach, Nelson removed the toilet and the water damaged wall beside it.

He then framed out the doorway for our custom aluminium french doors. These will provide a second entrance to the back of the house, while simultaneously letting more light and warmth into the northernmost corner. The new exterior doors, combined with an added doorway from this room into the lounge, creates a much more light, warm, and livable living space.
Then it was time to add the insulation.

And finally, this is what the kitchen looks like now, panning along the same view as the combined shot above.

We have since plastered and painted an undercoat. As I write, Nelson is pouring the foundation for our Shacklock multi-fuel stove, which will serve cooking and heating functions. We still have decisions to make about cabinetry and flooring, but we're getting closer.
And so that's where we're at. The 8 months have gone by quickly, and to be honest it is surprising to see the progress when we lay it out in pictures like this. It's a bit of a motivation booster! I think we can, I think we can. The finish line is in sight (although given my husband's love of creativity, I have a feeling this house will never really be "finished").

What have the past 8 months brought your way? What are you most proud of accomplishing since November?


-June Cleverer

Update 2: The front half of the house

Here is the second of three posts designed to bring you up to speed on the scope of this project so far (here's the link back to the first post). This post will focus on the southern four rooms of our house. These rooms actually make up the original part of our house, built around 1910. The northern lean-to, which I will talk about in my next post, was added on about 10 years later.

The original house consisted of four rooms and a central hallway. These are the bottom four rooms in these layouts. They are the ones that have received the least amount of demolition and rebuild, but that's not to say that the transformation is not dramatic.


The first time we walked into our house, we saw a hallway that stretched the length of the house. It was filled with dust, rubble, and long lengths of Hardiplank.


We have since sealed up an old doorway that was halfway down the hall and have hung a door in it. This has effectively sealed off the southernmost two bedrooms, and created an airlock in the hall entryway. Now when you walk in the front door you stand in this entry, and are greeted with our coats and boots.
When we moved in, the two southernmost bedrooms were filled to the brim with rubbish. I hate to disappoint, but they are still filled with rubbish. Only now its our rubbish. One of the rooms is serving as our indoor tool shed and the other as our indoor bike/ surf shed. They are too messy to picture. Maybe another day.

Moving down the hall (through the new doorway) you arrive at our bedroom on the left hand side. When we arrived this is how it looked:
It was stuffed full of windows, cabinet units, bathtubs, even a kitchen sink! Now it is a cozy little nest with gold curtains and a down comforter. Yummmm.

Across the hall is a room that we called "the dungeon" when we first arrived. It was dark and gloomy with dirty old carpets, moldy curtains, a massive boarded up window, and a giant hole in the floor. We didn't do any work in here for months. I think we were afraid.
But now, thanks to some demo work, we have converted the dungeon into a great open-plan lounge off of the kitchen. There is still tons of work to do here (like flooring, wall coverings, and doors), but it is already a nice sunny place and joyful space to live in.

I think what amazes me most, is how light can play such a critical role in the transformation of a room. The rooms in our house that were originally our favorites to be in are now the ones where we spend the least amount of time. And ones that we avoided initially, have become our living spaces.

Our intention was to design based on the principals of passive solar, making the most of the sun's energy to heat our home. But through the remodel we have ended up with a house that is not only warmer and lighter physically, but also more comfortable and joyful emotionally.

So what do you think? Are you surprised by our progress? Did you think we'd be further along by now? Any words of advice as we get to the "finishings"?




-June Cleverer

Intersections

I reckon life is all about finding balance. And because we live in a dynamic world, the balance point is always changing. On this project we are looking for balance not only between eco and thrifty, but also factoring in the New Zealand building code and the potential for wide applicability across society and across the world. In other words, we are looking for the intersection of eco, thrifty, legal, replicable, beautiful and attractive to people other than already committed Greenies.


To my knowledge this is a unique endeavor. This project represents an everyman's/woman's approach to permaculture. There are lots of examples of eco-villages and perma-farms and expensive bespoke eco-homes. But in the foreseeable future, the vast majority of people will never live in such places. Most people in OECD nations live in places like this.


Well, much nicer than this actually. But we did not want to be accused of cherry-picking.


In response to Richard's comment on the last post, I'll give an example of the intersection mentioned above using insulation. Pink Batts are widely available, recognized by almost everyone, cost-effective, meet the NZ building code and contain up to 80% recycled content. Meeting (and exceeding) the NZ building code is essential to this project. So the options of insulation included Pink Batts, polypropylene batts, and wool batts. (We did not consider blown in cellulose too closely because we wanted to do the job ourselves to ensure quality installation and to keep costs down.) Polypro batts are made from recycled plastic and the wool batts are made from...wool. Both are more expensive and less available than Pink Batts.

Some people like polypro batts because they are so soft and easy to handle. But in terms of insulation, handling should be (!) a one off. I do not mind handling Pink Batts. Once they are installed, I don't plan to touch them ever again.

Some people claim that wool batts are the most eco option possible. I question that thinking. Have you seen the unsustainable ways sheep are grown in NZ? A holistic look at the ecological footprint of wool batts must include soil erosion, herbicides, and nitrogen fertilizers. Some might argue that the ecology, soil health and water health of NZ would be much better off with fewer sheep.


In the end, the insulation intersection for this time and place and the goals of this project was Pink Batts. For the equivalent cost of polypro or wool we were able to exceed the building code at a higher r-value. In other words, we have a warmer house at the same cost. By using an innovative installation technique (see Bridge to Nowhere), we reap the benefits and can share this under-utilized approach with others to replicate from Auckland to Alberta.


Peace, Estwing

Update 1: The Exterior

We are getting to a point in this project where a lot of the major work is done. Since October, we have knocked out walls and built new ones. We have re-wired, re-plumbed, and re-inhabited this 100 yr old abandoned house. Before we get onto the finishing details, I thought you might appreciate a look back at progress so far.

The first of these update posts will take a look at the exterior. From the beginning until now.

The back of the house:









And the weed infested lawn turned garden:








If you think those are dramatic, wait until you see the inside!




-June Cleverer