Adding an enclosed patio

[Joe Blake]

I moved into this house about 10 or so years ago. Although it is of double brick wall construction it was not insulated in the ceiling and consequently required a lot of work (and energy) to keep it either warm or cool.

About 5 years ago I started insulating the ceiling space with fibreglass batts. Because of increasing mobility difficulties due to arthritis of the feet, I wasn't able to complete the task, but nevertheless it has made significant difference, and over the last 3 years, I have used no artificial heating, and only electrical cooling for 4 days in the last 12 months. (And since those were the days when I was generating more power from the PVs than the aircon was using, I don't think that counts.;))

Here is the western face of the house, with its shadecloth curtains.

http://i82.photobucket.com/albums/j245/saxeharp/house/rear01.jpg

I have now got a solar hot water system and (in this photo) 1 Kw of photovoltaic generator.

Last year I caused work to commence on adding a patio, enclosed, with a section of transparent roof.

http://i82.photobucket.com/albums/j245/saxeharp/house/patio04.jpg

I have installed an 1100 litre water tank to catch roof rain runoff.

http://i82.photobucket.com/albums/j245/saxeharp/house/patio02.jpg
http://i82.photobucket.com/albums/j245/saxeharp/house/patio05.jpg

The transparent roof allows sunlight to shine of the photovoltaic panels of my two electric trikes, as well as a "hothouse" effect in winter, which is great for drying my laundry when the day is overcast.

http://i82.photobucket.com/albums/j245/saxeharp/house/patio07.jpg

Over the last three days our minimum temperatures have been in vicinity 2-3 degrees C, with some places in the suburbs reaching -0.6 degrees C, which is 0.1 degrees off our coldest temperature ever recorded.

By using a small 40 watt electric fan

http://i82.photobucket.com/albums/j245/saxeharp/house/patio09.jpg

I can blow the warm air into the inside of the house via the rear door.

http://i82.photobucket.com/albums/j245/saxeharp/house/patio06.jpg

Although the door is of very light construction, by the application of "double glazing" principles to the glass via a sheet of heavy duty clear vinyl, as well the windows, and using "bubble wrap" on the non-glazed portion of the door, I've reduced heat transfer in both directions, so in summer time I get more heat entry through the uninsulated areas of the ceiling, which I can plot using a non-contact thermometer. I'm hoping before summer comes to pay a contractor to come in and complete the insulation. In the meantime, I've created a partial solution by taping kitchen aluminium foil to the underside of the ceiling inside the house, just where the hotspots are. This seems to have been pretty worthwhile, and in the previous summer it made a measured 3-4 degrees difference in the ceiling temperature.

http://i82.photobucket.com/albums/j245/saxeharp/house/P5070001.jpg

As you can see, the patio also doubles as my bicycle parking area, as well as shelf storage. And if ever I sell my bicycles, I've got a great spot for a small indoor vegetable garden.:p

Joe

[Joe Blake]

A couple of weeks ago I added a second 1100 litre water catchment tank. I'm hoping that, as well as giving me pretty much year round rain water, it will be useful in moderating the temperature in the patio area.

As mentioned previously, I've got a water condensing machine, which takes atmospheric water, condenses, filters and sterilises it. In summer time it uses about 2-3 kWh per day. However, with the availability of rain water, I only need to run for a few minutes each day to filter and sterilise it, so having the tanks saves me a couple of kWh per day. It uses reverse osmosis, charcoal and mineral filters, as well as ultra-violet light.

Joe

[Rob Beckers]

Very nice patio Joe!
Besides being a buffer that insulates the house a bit more from the outside, it should also be a very nice place to sit in winter and catch a few rays. I know your winters aren't as cold, but there are probably still plenty of days that it's not too nice outside.

I would love to add something similar to my house, both for sitting "outside" in winter and growing stuff that normally wouldn't survive in our climate. What holds me back is that my place does not have an obvious spot facing south where this could be added, and I still have not figured out how to keep it from getting -20C (or less) in winter if there is significant glazing without heating.

As to insulating the ceiling inside: Wouldn't this work better if you added insulation on top of the ceiling? I don't know if you have access to the space under the roof. That would be the place to add insulation (fiberglass or similar) to the top of the ceiling below, and possibly a radiation barrier (alu-foil) to the underside of the roof.

-RoB-

-RoB-

[Joe Blake]

As to insulating the ceiling inside: Wouldn't this work better if you added insulation on top of the ceiling? I don't know if you have access to the space under the roof. That would be the place to add insulation (fiberglass or similar) to the top of the ceiling below, and possibly a radiation barrier (alu-foil) to the underside of the roof.

-RoB-

-RoB-

That would be best, but because of my mobility difficulties, I'm not able to finish putting the remaining fibre glass batts in. I'm just trying to find someone about the size of a jockey who can crawl into the space to finish off the job. I could possibly have done it before I built the patio by lifting the roofing tiles from outside and laying the batts that way, but now the patio is there, I'd have to actually get up on the roof tiles.


It's more of an annoyance at the moment than anything else, and I was just using the aluminium foil as an experiment to see if it worked.


The patio is actually on the western face of the house. The builder suggested if I wanted to insulate the patio roof (bare metal and polycarbonate) I could buy sheets of styrofoam which could be taped to the metal beams, which would reduce heat transfer, which might be helpful in keeping the -20 degrees outside where it belongs.

A couple of the ideas which crossed my mind as I was planning in my head before committing to paper was (a) to build into the concrete pad a series of water pipes to act as under floor heating, linked to (b) a solar water heater. Alternatively, I was going to place the "under eave" water tanks so that the broad side faced north, and paint them matt black, so they would absorb sunlight on one side, and then radiate it on the other into the air space. Along with that, use a reflective drop-shade on the sunny side of the tank in summer to minimise water warming, and the dark side of the tank would absorb a bit of heat. However, I didn't use any of these idea for various reasons, mostly to do with the need to have the available window space on the north side available to put photovoltaics there.

Another idea which I considered was, instead of using the weatherboard wall and the windows, to install roll down transparent blinds of heavy vinyl. If you put those on the outside of your outbuilding, you could roll them down at the start of winter, lock them to the ground, and create a permanent air gap insulator around the walls. Some of the companies that make such things for alfresco cafe areas etc even put heavy duty zipper fasteners on so they can all be linked and sealed. Sort of like huge double glazing.

But yes, Rob, you are quite right, it is just GREAT to have a sitting place, especially in winter. It's a great little workshop area for my small scale experiments in all sorts of things. Just last night I was sitting out there rewiring one of the PV arrays for my trike.

Joe