The Pink Bat Rip-off

[Julia]

Something in black would trap heat but wouldn't trapped heat generate algae?

Do you mean algae in the water? Not as long as there's sufficient chlorine in the water.
Remember you're talking about in winter only bringing the water up to what it would be without heating in summer.

 

[DocK]

having helped my dad install roof insulation in 100+ houses in my early uni years I was happy that the insulation I received was a good 4 inches thick. it was also not "dusty" like some of the product we had been forced to install.

The guy did a good job and I actually got him and his dad to do a few other jobs around the house as they were reasonably priced for quality work.

the insulation certainly stops the extremes of heat / cold, but does mean the upstairs rooms stay hotter in summer, and can take longer to warm up in winter.

Am thinking I need to get something to bring the air from outside into the rooms. wouldn't take much to adjust the temperature if i could do that.
Probably hasn't reduced summer electricity consumption so much, but during winter I've seen a big drop - have two Thai guys renting rooms and I joke that they think winter is anything below 28 degrees

We had insulation put in the roof and west-facing wall of our home when it was built, 17 years ago. A couple of years ago I was complaining to a taxi driver about how hot the kid's bedrooms got upstairs, and wondered if the insulation actually made matters better or worse. As taxi drivers usually know everything , he was able to suggest a great solution - whirly-gigs. I did a bit of research (there are some good threads on the subject on Whirlpool forum) and we installed 3 on the roof when Bunnings next had them on sale. I can't say the difference has been dramatic, but it is noticably at least a couple of degrees cooler at night upstairs than it used to be. I still think a flip-top or wind-up-and-down roof to allow all the heat to escape is a fantastic idea (patent pending), but so far have been unable to make a fortune by designing one.......

 

[Julia]

I've always wondered re the whirly gigs whether - if they make it cooler in summer - they would also let heat out in winter. What do you think?

 

[DocK]

I've always wondered re the whirly gigs whether - if they make it cooler in summer - they would also let heat out in winter. What do you think?

I feel the heat much more than the cold. We tend to use the airconditioning during late afternoon/evening in summer, but very rarely need any heating during winter - especially on the second storey where the bedrooms are.
I believe the most effective way to use whirly gigs is to have vents in the ceilings of the upper rooms, which can be opened in summer and closed in winter according to need. More effective yet are powered venting systems designed to evacuate the hot air from the roof cavity at night - I'd like to be in a home with one of these to experience the effect - it sounds logical in theory, but involves fans and motors etc, and we haven't bothered. We've simply put the whirlygigs in and relied upon the gaps between roof tiles to provide the venting required to allow cooler air in to replace the hot air hopefully being vented out. In summer all the windows on the ground floor are open and allow a flow of cooler air from outside to travel upwards through the house to replace the hot air expelled from the roof cavity. (We sometimes open the manhole on the upstairs ceiling to assist with this). In winter, these windows are shut thus restricting the airflow through the house. As I said, the results are not dramatic, but every little bit helps on those hot summer nights. I've linked a couple of threads on the subject on other forums, if you are interested enough to want to read further:

http://www.ata.org.au/forums/topic/1592
http://forums.whirlpool.net.au/forum-replies.cfm?t=1588528

I'd welcome Smurf's comments on this subject - he's usually spot on with this sort of information.

 

[sydboy007]

I've always wondered re the whirly gigs whether - if they make it cooler in summer - they would also let heat out in winter. What do you think?

I had a couple installed about 10 years ago. It definitely made a big diff in summer, but also notcied the upstairs room were a bit colder in winter.

Still, with it being easier to warm up than cool down it was a compromise I was willing to make.

I just need some filtered fan system that would bring in the outside air when it's cooler / warmer outside than in the bedrooms.

Thinking I'l have to stop procrastinating and start googling.

 

[GregoryLawrenc]

Fibreglass batts (Pink Batts, Bradford or similar brands) are the way to go in my opinion unless there's a specific reason to use something else. It won't burn, won't rot, doesn't wear out and so on. The only downside is it's not pleasant stuff if you have to work in the roof after it's been installed - electricians in particular don't like it for that reason but apart from that it's a good product.

Foil has a worthwhile use in a hot climate for keeping the heat out during the day, but isn't a real alternative to bulk insulation (batts etc) in a cool climate.

Polyester has advantages in any area that's likely to be regularly accessed since the batts are non-irritating to the skin and require no protective gear to install. You really could go to sleep on them if you wanted to. It's more expensive than fibreglass however and you do need to make sure it's a quality product and not something that will burn easily (there are quality products available, just make sure you get them).

Forget the rest unless there's a specific reason to use them in my opinion. Cellulose blows around, makes a nice rat / mouse nest and is flammable. Loose fill rockwool also has the blowing about problem although at least it can't burn and isn't overly attractive to rodents. Foam can work if done well but there's lots of horror stories of it going wrong. And don't even think about straw etc - way too flammable.

And don't forget the R rating of any type of insulation you install. Vic / Tas go for 3.5 or 4 (more if you've got $ to spend). In warmer climates a bit less should be OK. There's an official guide that lists each area somewhere and it's good advice. Don't have a link unfortunately.

it looks like worth old thread for me.. i am searching for some fibreglass bat information and there is plenty to gain here..I will try to get one now asap and share my own experience very soon

 

[bellenuit]

it looks like worth old thread for me.. i am searching for some fibreglass bat information and there is plenty to gain here..I will try to get one now asap and share my own experience very soon

I used a product call Greenstuff batts a few years ago. It provides all the insulation properties of fibreglass batts, but without the environmental and skin irritation issues. I think they may have cost a few dollars more, but not a significant difference. Well worth not having the worry of needing protection to install or later when going into the attic to do other things. Bunnings used to sell them then.

http://autex.com.au/products/Insulation/GreenStuf/Batts-for-Walls-and-Ceilings