Cooling the house on a budget - ideas please?

[JustAChick]

Hi All

Have just discovered this thread and am very excited (and somewhat amused) by many of the threads. Hope you can help me with my query:

We live in the Dandenongs (Vic) in a split level house with minimal insulation (part roof and part walls of the renovated section but the rest of the house has NO insulation).

Our house is incredibly hot in summer and I'm looking into cooling options.

Split system aircon I am told will not work well with our house design as refreigerated air does not "turn corners well". Evap Cooling would be better but is expensive ($3800) and we have a questionable roof cavity space so the guy wasn't sure if it could be done.

I am now down to outdoor blinds (Vistaweave vs Canvas), but again, around the $2500 mark, and possibly a couple of whirlybirds (which seem to get a bagging on here?).

Final option is to build a verandah along the front (west facing) to shade the windows but I am concerned about losing light and heat during the winter months.

Suggestions? Sorry for the long post but I am a chick after all and long-winded is what we do well!

Thanks,
K.

[dennford]

First of all unless you have air conditioning of some sort the insulation is not all it is cracked up to be. The first day of hot weather it is a help, by the second day the house is a little warmer and by day three the house is quite warm - now the crunch is that after three days of hot weather the house is no cooler during the day but during the night the insulation actually keeps the heat in, whereas an uninsulated house does cool down at night time.

Now onto the air conditioning; I don't understand the turning corners bit but the important points are 1/ do you wish to cool the whole house or just one or two rooms ( maybe a bedroom and lounge) 2/ Is the running cost of high importance. 3/ do you wish to use it for heating in winter.

Denn

[Master Splinter]

I know what they mean by 'the air doesn't turn corners well' - the cold air mass doesn't really have much velocity after it leaves the unit so it spreads out really slowly - even an open doorway is a 'barrier' to getting the cold into another room.

Ceiling fans and lots of open windows; have the fans on a timer for 3 am (or leave them on) if you get colder nights and try to get as much of that cold through the house as possible to drop the overall temperature for the daytime.

Or a reverse cycle split air conditioner for each room that must be comfortable (you can get them from around $400 and up these days, so its not a huge capital expense for smaller rooms). My rule of thumb for reverse cycle is that what it saves you in winter (they are about three times more efficient than other forms of electric heating) you spend on cooling in summer!

By all means, shade the west facing windows - they will be your biggest source of heat gain in summer. Have a look at the DIY awnings in Bunnies to save a bit of money. Personally I really like those metal roller shutter things; however I really don't like the huge prices that are charged for them, they seem to be in the same markup league as jewellery.

Deciduous trees are good for shading, but aren't a quick fix!

Don't worry about loosing too much sun with a verandah - look up some of the solar design sites and read about winter and summer sun angles.

[woodbe]

One house we had was an absolute hotbox. It had cathedral ceilings and split level, minimal insulation and lots of air gaps in the brickwork. On a hot day, you could hardly breathe inside after getting back from work.

We got quotes for reverse cycle AC and because of the house design, installation was going to be a nightmare. They were talking about running small ducts through the tight spaces and in the end we ran away after we got the quote, it was horrific.

We found a bloke who installed evap coolers and got him to come down and have a look. Ducting was out of the question, but because of the cathederal ceilings, he proposed roof mounting a big evap unit with 2 outlets, one upstairs and one at the same level but blowing into the split level area.

We went ahead with the unit, and it worked a treat. When we got home from work, we'd walk in, open all the windows and doors and let the unit rip. It exhausted all the hot air in about a minute, and the place was very pleasant in about 5. Most warm days when we were home, we could leave it ticking over on low, cost almost nothing to run.

woodbe.

[bitingmidge]

Insulation is the best investment you can make. Properly insulate the place before you do anything else, and you'll get the benefit in winter too.

Getting cross ventilation is the next best. See where woodbe says "we'd open all the doors and windows"? Cross ventilation!

With the house thus modified, you should then sell it and move to somewhere more pleasant!

Cheers,

P

[johnc]

I wouldn't be concerned about a veranda shading the windows. In winter the sun is low enough once it is in the west to get under anything, the shading effect in summer will serve to break the heat build up on that part of the house. We have a house that faces west with veranda on half and awnings on the other half. The veranda area remains pleasant right through the year with the exception of the hottest days. The awning area is a hot box in summer, the awnings do help considerably but those rooms remain hotter than the other area. Recently we finally put a split system into the kitchen area which keeps the living area fine, but the cool air does not transfer to the remainder of the house that well.

In the end cost is important, both set up and running. Passive solutions are cheapest in the long run with air-con etc best used to take out the peaks rather than to just keep a home bearable to counteract poor design.

[namtrak]

On a budget I would:

1. put insulation wherever I could - this is a must. $4 per sqm

2. put blinds on the inside of the west facing windows. $400 per window

3. put fly screens on everydoor and window in the house. $200 per opening

4. plant trees and shrubs around the house. $5 per plant

5. put one or two whirlybirds in the roof depending on the size of the roof cavity. $200 per whirlybird incl. installation

6. consider ceiling fans in some of the bedrooms. $250 per fan incl. installation

Then over summer, keep the front blinds closed until the sun has passed over the roof, open the house up at night (this will cool it down remarkably), and close the house up during the day.

Why do I say all this? Firstly we have been renovating our house and last summer I removed our split system, and was not able to put it or fans back in over summer. As a result we had to basically live with doing items 1 to 4, and we found we survived quite comfortably. There was about 8 nights which were pretty hot largely because there was either no wind or the accompanying wind was hot. Other than that the house was quite cool. As a matter of fact this summer, our only addition will be whirly birds, as we have decided not to reinstall the split sytem at this stage as we think we can live without it.

And secondly, I believe air con has made us all soft. As kids we were largely bought up without air conditioning and our parents used to resort to opening the house at night and closing it during the day.

Thirdly, well it's a greenie thing!

Next, we bought a family season pass to the local pool and basically the kids lived at either the pool or the river all summer rather than squat infront of a TV all day.

Finally, our electricity bill with the air con was around $500+ per quarter, by doing it the old fashioned way we slice about $350 off that bill.

And for the record Albury regularly tips over 40 degrees and had next to no rain all summer

[arose62]

Visit your local library, or newsagent, and have a look at a greenie magazine called "Renew".

I grabbed a couple from our library, and one had an article where a guy was looking for a really effective and cheap way of blocking heat coming in through his large windows.
The end result was he found bubble-wrap to be the best: still let light through, but was cheap, and one of the best insulators. Plus, easy to fit, and easy to remove if needed.

Cheers,
Andrew

[JustAChick]

Thanks for your replies. Some great suggestions there.

I think we can probably live without aricon/evap cooling too if I can find a way to stop the house heating up so much. I would prefer a green option if we can.

We only need cooling, not heating (we have a Coonara and Gas Ducted Heating). We have ceiling fans in living areas and bedrooms - great at night but in the day they just move the hot air around.

One great thing about being on a hill is that when the cool change comes, our house cools quickly.

I think insulation may be the way to go first and we can look at other options from there.

Appreciate all your suggestions!

[Mcblurter]

I agree with Namtrak. The only thing I would add is that we put in some openable skylights. A great way of getting ventilation, open the front door and one of the skylights and it's like you turned a fan on!
Insulation is the most important and will save you heaps on your heating bill as well. We got gas ducted heating as we have a concrete house that can get very cold and we have two young children. Often we put it on 19/20 degrees max for 15 - 30 minutes and then the whole house is warm and maintains warmth throughout the night.
Cheers
McBlurter

[bsrlee]

I have no idea of the cost, but there are a number of adjustable louvre roof systems for verandas on the market - crank it to full open in the winter to let light & heat IN, crank it almost closed in summer to keep light & heat out (leave it open a crack to let super-heated air out from underneath in summer).

The cheaper, long term solution would be to put up some sort of pergola with wires, then grow a deciduous creeper like Wysteria (sp?) over it - cool shade in summer, pretty flowers. Or grapes - shade & fruit.

[bpj1968]

Insulation works as does whirly birds. Our last house was a single level tile roof and had insulation, except for the shaft around the skylight. It was amazing how much heat came from the few square metres of uninsulated wall and a clear skylight. One bag of batts $30 and and a light diffuser fixed that. I also istalled one whirly bird.

We had one old wall refrig cooler. We would only ever use it after a day of hot weather. However after taking those few steps we rarely used it.

We now have a split level house. 2 story at front. THere was insulation only above the kitchen bathroom and lower bedroom. The upstairs had none and the walls that exposed to eth roof space were hot to touch. Since then i have insulated the roof, including the walls onto the roof space. Even though I itched for a few days (that stuff gets through anything) it was well worth it.

[JustAChick]

Checked out the louvre systems (Vergola is one I found) but it is apparently very expensive and the guy didn't reckon it would do much to stop the western sun hitting the windows.

I like "bsrlee"'s idea of growing wysteria or ornamental grapes over the top, however as mentioned, it is a longer term project.

I think for this summer, I will go and buy some cheap and nasty blinds from bunnings to hang on the outside of the window and aim to have the rest of the house insulated and all gaps stopped up before the following summer.

Perhaps by then we'll have won powerball and I'll offer to cool all your houses for you!

[echnidna]

While insulation is important, Keep an eye on ebay for a roof mounted evaporative cooler. Sometimes they go rather cheap. (I got one for $102)

[mitasol]

I have a house with a cathedral living room and faced similar problem. We have an 8KW inverter system up high (cold air sinks) and run ceiling fans to circulate the air - works like a dream and being an inverter is costs less to run. I live in the tropics so evaporative was not an option.