central heating / insulation

[jackiew]

I'm bringing my 1920s all electric weatherboard into the 21st century. The previous owners obviously didn't feel the cold as their is bugger all insulation, gaps everywhere and a single electric heater in the 8m x 4m x 3.25 m high lounge and thats it for the entire house.

Coming from the uk I'm used to hydronic heating but the quotes for it are double that for ducted. The difference would pay for a lot of extra insulation and probably the next 10 years worth of gas.

Question 1. One fitter suggested putting the ducted heating unit under the house ( there is a lot of room under there ) and one fitter suggested putting it outside. It seems to me that fitting it under ones wooden floorboards might be a tad noisy ( like a drum ) but on the other hand having it outside might annoy the neighbours ( although as their airconditioner annoys the hell out of me its very tempting ). Does anyone have any opinions on the best location for the unit?

Question 2. Has anyone installed either the concertina foil insulation or the board with foil either side under their floors and did it make a difference to warmth / cooling. They have both on display at the Timber Advisory place in Melbourne. I can't say I'm looking forward to spending a day or so on my back among the spiders fitting the stuff but it will be worth it if the temperature in my bedroom gets over danger of hypothermia this winter.

[Gumby]

Go withn the vast majority.....outside. Dont worry about the neighbours, I reckon 90% of homes have them out there and you can't here it from inside, particularly the modern units. They are then much easier to get at if there's a problem. I don';t fancy the idea of lots of gas flames roaring away under my house either !

[Gumby]

omg ! here = hear....sorry:rolleyes:

[Sturdee]

When I got gas ducted heating installed I did not want it under the house and have ducting running through my workshop which is built under the house.

So I got it installed in the roof space with the ducting laying there as well with ceiling vents instead of floor vents.

Works well and leaves the useable storage/ workshop space intact.


Peter.

[Gumby]

Orange painted ducts ?
:D

[Sturdee]

No, orange paint is too valuable to use outside the workshop.:D

Peter.

[MrFixIt]

Originally posted by jackiew
One fitter suggested putting the ducted heating unit under the house ( there is a lot of room under there ) and one fitter suggested putting it outside.

Hi

Never used ducted heating. However my thoughts would be to place the unit outside and run the ducts under the floor and have the outlets actually in the floor. This would of course allow the natural air flow to function effectively (ie hot air rises).

I would consider posing this question on a US based forum too, as they are all too familiar with this kind of heating in the colder states.

Regards

Peter

[Barry_White]

Just a point ducted heating works more efficiently from the floor whereas ducted cooling works more efficiently from the ceiling.

I would go with the mob and put the gas unit outside.

As far as insulating under the floor it depends on a couple of things.

If you have carpet on the floors it would not make any significant difference. On the other hand if you have bare floor boards and the wind can blow under the house it can make a difference.

With heating the most important place to put insulation is in the ceiling and the next most important place is in the wall. Wall insulation can be put in by Bradford Insulation using granulated rockwool which can be pumped into the cavity of the walls.

The windows come next and the best way to insulate them is with heavy drapes that actually touch the floor. This stops the glass chilling the air and causing the cold air to drop from the glass and actually cause cold draughts without the windows being open.

Fit foam tape around the jambs of all external doors and and fit draught excluders to the bottoms of the external doors.

Doing all these things will make a huge difference even without the heating.

How do I know. Well amongst my many careers I used to install heating, air conditioning and insulation.

Just as an aside there is plenty of expertise in OZ with out asking the yanks.

[soundman]

Been in a few cielings, I recon the foil fold up bats are not good. the r value isn't great & the firts time a contractor gets in your roof he has no choice they are buggered.

Polyester or poly/wool I recon has to be the best choice now though dearer then fibreglass or rock wool.

Ive just used some & I much more interested in doing my own cieling now. I hate being itchy.

Also why dont you reverse cycle aircon. has to come out cheaper in the long run???
Also much less fire risk.

[Greg Hudson]

Having recently purchased a property with no insulation, (and having just installed it myself) I can wholeheartedly agree with Soundman that Polyester Batts (R3.5) are the best. Easy to lay, and no glass fibres embedded in your skin. It was a crappy job, but has made a HUGE difference to the inside temp.

We also installed reverse cycle aircom (Heating & Cooling) which (I'm told) is THE most efficient form of heating. Supposedly, 3 times more efficient than a bar radiator of the same wattage.

Our property also has a large under floor cavity - open to the weather, and being in a sub alpine area, it gets mighty cold here, so we will be installing underfloor polystyrene - something you might want to consider.

We also installed Polyester Batts in the exterior walls (easy because we were replastering anyway).

In our Melbourne property, we have Gas Ducrted heating in the ceiling (because the building is on a concrete slab) and it is NOT very good. As someone else mentioned, heat rises... and with the ducts in the ceiling, that's where it stays!!! With the thermostat set at 23 deg I am still stitting in the Loungeroom with a blanket. Damned ridiculous !

If you decide on gas, then put your heater outside, and run the ducts under the house - you'll be much happier (and safer) that way.

My 2c worth...

Regards, Greg.

[seriph1]

we just paid $6700 for in-ceiling ducted heating in our VIC weatherboard - if it had fit under the floor, the price would have been around $4200

ppl rarely insulate under homes here, though it cant hurt - maybe wait til your ducted heating is in to see if you still need to though.


If youre in Melb. please let us know what area and what else you have planned for it.

cheers

[MrFixIt]

Originally posted by Greg Hudson
We also installed reverse cycle aircom (Heating & Cooling) which (I'm told) is THE most efficient form of heating. Supposedly, 3 times more efficient than a bar radiator of the same wattage.


It is important to note though (for those not aware) that the "efficiency" is in the "coverage" NOT the amount of heat. In other words the air blows around the area, whereas the bar heater is relatively concentrated around the heater itself.

You can only get so much heat out of 1kw of electricity :-)

Regards

Peter

BTW In heat value the most efficient heating is gas. More heat can be created by 1 unit of gas than the same unit of electricty

[Gumby]

Originally posted by Greg Hudson


In our Melbourne property, we have Gas Ducrted heating in the ceiling (because the building is on a concrete slab) and it is NOT very good. As someone else mentioned, heat rises... and with the ducts in the ceiling, that's where it stays!!!

WhaT about installing a ceiling fan ? If you get one with a reverse switch and set it on low speed, it circulates the warm air around the room. They are almost essential if you have a Coonara type wood heater. Without one, you could cook a steak up near the ceiling and freeze a beer on the floor! Once we put one in here, it made all the difference.

[zathras]

Yup ceiling fan's are good.

The return air for our ceiling ducted heating is also in the ceiling. That room never got warm as the warm air was sucked out as soon as it was put in. :mad:

A ceiling fan fixed the problem and now that room is the warmest room!

[seriph1]

pretty bizarre having the return air in the ceiling!

Agree that fans help heaps

BTW - Hi neighbour!

Kilmore here - kettle's on any time you wanna talk timber

[email protected]

[Gumby]

Originally posted by zathras
Yup ceiling fan's are good.

The return air for our ceiling ducted heating is also in the ceiling. That room never got warm as the warm air was sucked out as soon as it was put in. :mad:

A ceiling fan fixed the problem and now that room is the warmest room!

That's ridiculous ! The air return in the ceiling ! Where'd they put the thermostat ? Next to a duct ???

[texas]

I had a house where the central heating unit was located under the floor, space was limited in the yard and I think not many 'external' models were available when it was installed (circa 1992). It wasn't noisy, just awkward to access when getting it serviced. You also have to think about the flu, got to get that out from under the house. Better to put the unit outside if you can.

[jane99]

We put heating in the ceiling 'cause didn't have any room underneath. Chose a Brivis (from memory) mid efficiency unit. It's excellent, don't have ceiling fans and have 3.25m ceilings but the air gets pushed down beautifully. The return is in the hallway down low. Didn't have insulation 'til recently but it certainly makes a difference, both to keeping the heat in, but also on days like today (30C in Melbourne) keeps the house nice and cool.

[seriph1]

sounds like an early calif. bungalow or Edwardian

:)

I WISH we had the American underfloor ducted specifically designed for period homes

multitude of quiet 50-70mm outlets with 150mm feeders

ah well - our in-ceiling stuff keeps us warm...and by the time I get through making the deep threshold between the maiin house and the extension, the return air nightmare will be invisible.

[bob w]

Gas ducted heating is certainly a very efficient form of heating, however the entire system is dependant upon the design of the ductwork and placement of the downjets and return air vent.
As stated in this thread hot air does rise and for that reason the return air vent MUST be located as close to floor level as possible so as to draw the hot air away from the ceiling, also the downjets should be placed so as to ensure complete coverage of the room.This together with accurate sizing of the unit required proper location of the thermostat and the calculation of heat loss factors is vital in the installation of an efficient system.
How do I know this? I was trained in this area by AGL and the major manufacturers of gas central heating units whilst managing an AGL agency in cold climate NSW.
Regards and stay warm,
Bob W:)

[jackiew]

I'm now convinced about putting the unit outside for ducted heating. Both the quotes I've had so far the guys sort of wandered round the house had a quick look under and then specified the system they would use. Neither of them were interested in the level of insulation of the house.

I've had two hydronic systems installed in the uk and also got a couple of quotes here and the approach is different. Actually measure up the rooms, ask questions about the insulation, go off and do heat calculations ( or go home and watch TV and specify the system during the ads perhaps ... )

Are the ducted heating guys just "experienced" at (gu)estimating or do they just go for the one size fits all.

The ducted heating in the rented homes I've lived in here has been uniformly abysmal. One house had floor ducts into enormous Cathedral ceilinged rooms ( no insulation anywhere ). Not worth turning it on. One newer home with vents in the ceiling ... would have been great if I'd wanted to sit on top of a ladder all evening, reduced to sat wrapped in a blanket in the lounge. One home where the gas unit was installed in the coat cupboard in the hallway and sounded like a falcon with a holed exhaust and only the closest room to it was reliably heated.

If only hydronic wasn't so expensive to install :-(

[dale]

We went for underhouse heating. Previously it was outside, but a small (fill it the eaves) extension meant there wouldn't have been room for the heater and a parked car.

The high efficiency brivis heater has a plastic gas exhaust (they waste virtually no heat at all) goes out through the brick wall.

You can just sort of hear it at night time, and it's under my son's bedroom (with thick carpet on it).

There is an access door right next to it so maitenance is not a problem.

[seriph1]

SIGH!!!!

As mentioned in a previous post, we paid $7000 for our in-roof heating system - last week we had a cold snap and turned in on to discover it wasnt heating properly....... so I got up in the roof for the first time since its installation only to find that the blue "tapes" they had used to keep all the ducting level and off the deck had come undone, the ducts were on the ceiling in a few places and the main "Y" junction had come adrift, requiring duct tape immediately..... fixed the problem but you just wonder what we are bloody-well paying for at thos rates!!!!!

There will be some added warmth in the suppliers offices this week when I get down there to have words with them.

there's my monday morning bitch-session out of the way

Sorry folks

:)

[Rocker]

One of the pleasures of living in Queensland is the schadenfreude that you get to enjoy from listening to Melburnians whingeing about the cold in winter. Nevertheless, it can get a bit nippy even here for a couple of months of the year. We find that the reverse-cycle air-conditioners we have installed work brilliantly at heating, despite the fact that we have cathedral ceilings. They have powerful fans which blow the warm air downwards, and only take a few minutes to warm up the open-plan main living area of the house which is 6.5 X 16 metres.

Rocker

[Barry_White]

As they say there is tradesmen and there is tradesmen. When I was doing airconditioning we hung all our duct with perforated steel strapping and we didn't rely on the duct tape to hold the duct onto the fittings.

We first put four tek screws in through the duct and into the fitting before we fitted the duct tape. The duct tape was only used to seal it not to mechanically hold it together.

[dale]

One of the pleasures of living in Melbourne is the schadenfreude that you get to enjoy from listening to Queenslanders whingeing about the UV & high rate of skin cancer (highest in the world?) all year 'round.

As well as tropical mosquito born diseases, & jellyfish :-)

[Bob Willson]

Are you having a go at biting midge here Dale, cos if so then I resent it on his behalf.

ps I have never heard any Queenslander whinging about the best rate of cancer in the world.On the other hand, I have heard lots of us thanking our lucky whatsits that we don't have to put up with suffering the whole four seasons in the one day as do some people who live to the South of us. :)

[bitingmidge]

schadenfreude Is that some brand of wooly underwear, for use when the heating goes on the blink?

:D

P

[dale]

No, schadenfreude is for when you pull the shades down so that the neighbours don't see you doing something that would make even Freud blush!

[seriph1]

I can almost guarantee ab-users of "that" German word were watching The Einstein Factor last night

:)

:)

:)

[HavinaGo]

Hi all, As a newbie who has been through the heating routine twice in the past 12 months I'd start by asking One question, do you need to heat the whole house?

We put in a space heater last winter and heat the living ares, but not the the whole place. So far it has worked a treat. For my mother-in-law, their only option was electricity based (Vic country near Echuca), the choice was reverse cycle air conditioning.

Efficiency is an interesting term that can mean:
a) works well
b) uses the natural resource effectively (ie heat in room rather than heat up a chimney) or
c) minimises running cost.

From the running cost view point, my back of the envelope calulations during Dec 2003 said reverse cycle airconditioning wins ... just. (Assume 5 *air conditioner, and 5 * gas space heater heater and VIC prices for natural gas and elec). Not sure what ducted does to those figures but friends at work had rude shocks with their systems that put me off exploring that path.

catch you

David

[MrFixIt]

Originally posted by seriph1
SIGH!!!!
....... so I got up in the roof for the first time since its installation only to find that the blue "tapes" they had used to keep all the ducting level and off the deck had come undone, the ducts were on the ceiling in a few places and the main "Y" junction had come adrift, requiring duct tape immediately.....

You have my sympathy :D

I was asked to add some evap aircon ducts to a rental property. Went up there to check out and measure up etc, etc.

Found out that where the ductwork was attached to the dropper there was NO duct tape to seal the connectors. The connectors were really cheap and nasty. There were gaps all the way around all three ducts, so the roof was kept nice and cool.

I took out all the old "cr*p" and fitted quality components (after finding out that I also had to seal the dropper), so yes, there are tradesmen and there are tradesmen.

I just had somebody install blow-in instalation. They got the job conditionally that I would pay ONLY after my full inspection. I know from experience that you can't trust many tradesmen these days.

The last time my house needed painting, I did not have the time to do it myself, so I had a "many years experience, older" tradesman do it for me.

After TWO returns visits at MY request, the job was STILL not satisfactory. I sent a two page list to the painters registration board (in WA) and it took a futher TWO visits WITH THE PRB INSPECTOR to get an adequate job. The best room in the house is the one he DID NOT paint :D

It is no wonder that people resort to DIY, now if only the reality programs RFI, etc could get it right when they show the viewers what to do :D:D

regards

Peter