Using permaculture ethics & design principles to transform an old energy guzzling bungalow into a showcase of sustainable design. It's about energy cycling, building community, self-reliance,creatively using & reusing materials... all without spending heaps of money.

Friday, November 18, 2011

The longest pelmet ever?

Design Principle 2: Catch and store energy

I spent quite a few months thinking about the best way to build a 7m long pelmet, and came up with this approach...
Living room pelmet under construction with extra support added to curtain rail to prevent sag
The finished pelmet, made with lining boards recovered from the original bungalow, oiled and varnished
...90x45mm pine battens were screwed into the box beams on the ceiling, supporting the structure. 75x19mm pieces of pine were attached at an angle to the battens so that they run vertically and a small chock of wood was added to brace them onto the rail brackets. The weather boards were nailed onto these mini studs. I added some extra support in between the curtain rail brackets using metal bracing off-cuts. I added a plain pine cornice and oiled and varnished the lot, so that it ties in with the rest of the room.
The diagram below shows how the pelmet prevents convection currents in winter, during summer our eaves do most of the work by preventing any sun from hitting the north (sunward) facing windows. Sun reflection off the decking and the external temperature transfer heat through the glass during summer. We close the curtains on really hot days, keeping the room dark and reducing the heat transfer as the hot air gets trapped between the curtain and the pelmet, unable to continue to rise up. Gaps at the edges of the curtains reduces the effectiveness of this though. Extra external shading would be better, but I have been reluctant to install sails as everyone that I know that has them does not take them down during winter. Options of easily removable shading or decidous plants are more appealing, but I haven't quite figured the best way to do that yet.
Curtains and blinds together with pelmets will help to keep heat inside the home. They prevent warm air from coming in contact with the cold glass. Source:
I was contacted by a teacher who was running the 'Home Sustainability Course' at Seymour's Go TAFE. She asked if she could take her group to tour our home during mid winter, and I was happy to oblige. As a bonus, one of the teachers that joined the group was an energy assessor who brought along his thermal camera. Wayne took some around the living room that show the effectiveness of curtains with pelmets in regulating temperature extremes and how aluminimum and single glazed glass act as thermal conductors.

Sliding doors on northern window (Aluminium strip between)

Thermal shot showing west living room window with curtain open

Same location showing west living room curtain closed (with pelmet)

Thermal shot of west wall showing timber studs acting as thermal conductors, not as dramatic as aluminium or glass though.

Thursday, November 10, 2011

Finishing touches

Principle 7: Design from patterns to details
There have been a bunch of jobs that I've been working on while the family have been in Japan visiting family. The types of things that I can live without doing, but haunt me every time I walk past them. The details.
The bathroom sink cover plate was quite a task, though a relatively small one. I tried to find a piece of timber that would cover the plumbing with a natural edge on the bottom. Of course there wasn't one suitable, so I had to make it up, gluing two pieces together.
I made up a template to get the shape that I was after and transferred this onto the red gum. Getting the curve to fit below the sink was a bit tricky without the right tools. A band saw would be great, but a drill and some wood files had to do.
I attached brackets to the inside and mounted the final piece from the back. It was oiled with linseed and painted with three coats of floor bio varnish so that it matched the rest of the bench.

Creating a template using cardboard to cover the plumbing

Cutting a curve through 35mm red gum using a drill

Joining two pieces of red gum using PVA glue and clamps

Finished job; sanded, linseed oiled and three coats of bio varnish
Principle 6: Produce no waste

When we moved in we were in such a rush that some of the I didn't get a chance to paint the floor as much as I would have liked. I gave the bathroom floor another six (or so?) coats of varnish to protect the timber, as it was beginning to show signs of water damage. I gave the toilet, hallway and kitchen floor another couple of coats after giving them a good clean and light sand.
The kitchen bench got another six or so coats too, as it too was showing signs of wear, and the silicon was touched up around the edges.
The Natural Timber Oil that I used for the north facing deck was very disappointing, but on the south side, where it is in shade and under cover it looks great. I decided to over paint the north deck with linseed oil instead, giving up on the 'polished' look, but re coated the south deck with the remaining timber oil as it has held up well. The north deck also needed some leveling out as the red gum had moved in places which created some tripping hazards.

Another six coats of vanish for the kitchen bench
Small areas of the red gum deck have moved and were planed and sanded back

Rather than continue to use the disappointing decking oil I decided to paint it with linseed oil
Front deck freshly recoated with Bio decking oil (2 coats)

Blog Archive