Thread: windows- insulating

My point was that her indoors will require drapes/ curtains anyway and you could probably kill two birds with one stone. Incidentally what would a Victorian know about Heat ??

Drapes are fine. Most people open them to let light in, and to see out, at which point the energy advantages go 'out the window'.

High energy costs negate arguments about our weather not being extreme. Every bit of heating and cooling costs, and a thermally efficient home needs a lot less of it.

Greg is correct. Retrofitting any of this stuff gets expensive in a hurry, especially if you factor in the perfectly servicable but thermally useless items that are replaced in the process.

woodbe.

If you can accept paying a premium, then I suggest you have a look at the Rylock architectural series. They are a double glazed, timber/aluminium composite window - aluminium outside and Vic ash inside. I have just installed them throughout the house I am building and don't regret one cent of the money spent. They look absolutely fantastic. I was so taken with the timber reveals that I used 140mm framing timber so that I could preserve them. The person who did the energy rating said he was amazed by the difference they made to the overall rating of the house.

Originally Posted by MarkV

My point was that her indoors will require drapes/ curtains anyway and you could probably kill two birds with one stone. Incidentally what would a Victorian know about Heat ??

Ahhh sunny ol" queensland

Sunny one day, perfect the next
(bugga the water shortages)

Great beaches,
pity bout the stingers 'n' jellyfish 'n' sharks 'n' crocs 'n' stuff

Where ya don't need heaters,
but ya gotta have air conditioning.

Yep - a real great place...................
for a winter vacation.


btw
I'm not even a messican,
born in Ipswitch , just prefer to live in VIC.
y'know - that place that usta be called the garden state.

Hi Metung,
What did you pay for the Rylock windows and what were the dimensions?

Originally Posted by Metung

If you can accept paying a premium, then I suggest you have a look at the Rylock architectural series. They are a double glazed, timber/aluminium composite window - aluminium outside and Vic ash inside. I have just installed them throughout the house I am building and don't regret one cent of the money spent. They look absolutely fantastic. I was so taken with the timber reveals that I used 140mm framing timber so that I could preserve them. The person who did the energy rating said he was amazed by the difference they made to the overall rating of the house.

There were 19 windows/doors overall and I just paid the lump sum for the job so I really don't know how much each item was worth. They had prices on their items at the local display centre and a 4.5mx2.4m 4panel sliding double door was around the $4000 mark from memory and a 2.1mx1.5m 2panel sliding window was around the $1200 mark.

uPVC double glazed windows nowadays are really good. The reality of the situation is that despite all the "official" recommendations on the benefits of batts & double glazing, the majority of people still are not convinced.

I personally feel double glazed windows are the way to go. Definitely for all West facing windows in warm weather/seasons. Even for other facings in colder climates, double glazing will help lower heating costs, because the thin glass panes (esp. in older homes) in older windows transmit the cold easily (they only block draught, but just touch the windows in winter and they'll be freezing, unlike double glazed ones). But of course, budget rules, and I'd suggest prioritizing and phasing in upgrades as budget permits.

Originally Posted by Ashwood

I personally feel double glazed windows are the way to go. Definitely for all West facing windows in warm weather/seasons..

Double glazing on west facing windows is no better than std glass, because double glazing doesnt stop radiant heat from sun on the glass getting inside the home. Worse still, as the double glazing allows the heat into the home freely via direct sunlight, it holds the heat in as the window insulates the air temp.

Double glazing for cooling purposes should either be done in concert with low e glass, external shading OR in buildings that are fully air conditioned constantly - so office buildings for example would benefit..

I think low e glass is the best of both worlds for Austrlias coastal climates because it slows heat transmission in both directions and more importantly lets less radiant heat throught from the sun. Although this woul;dnt hold for well shaded due north glazing, as these allow winter heat in as well, so double glazing would be perfect for summer shaded, winter sunlight exposed glazing.

Perhaps to elaborate further, I am referring to installing double glazing systems in the market, which you will find in the market often include various features like the double glazed sealed system, low E glass, tint, reflective coatings, sometimes inert gases in the double glaze systems.

When we looked at installing these, we were bombarded with technical performance measures (U, E, SC, SHGC) and various overall window energy/star ratings.
I'm no expert on glass, and won't even attempt to talk about the above, but list below a few links which cover these subjects, for interested readers.

http://www.wers.net/
http://www.efficientwindows.org/glazing_.cfm?id=6
http://www.socalgas.com/construction/builders/Builders%20Resource%20Guide/Window%20Energy%20Concepts.htm
http://www.double-glazing-uk.co.uk/Low_e.asp


I'd agree with pharmaboy2 that low-E glass would be much better if a double glazing system uses it, but would add that most double glazing systems in the market would already reduce heat transmission compared to typical single glazed window systems.

I can say from our own case is that we installed double glazed window systems (slightly tinted, low E, reflective coat on some ie. Western facing) in a new part of the house, and the difference is very distinctly apparent - direct evening sun on hot days are much cooler compared to the old area with similar facing, and it also feels less freezing on cold days compared to the old area. An added benefit is that you hear much less of what is happening outside.

Ultimately, once decides what works best for ones circumstances, but hope the above info/feedback is helpful.

I agree with you Ashwood. What has caused me a lot of irritation over the last few years is the requirement to understand all this stuff to save yourself from being sold a load of rubbish from people who should know better.

In a hot climate, the number one rule is to keep the sun off the glass. That goes without saying, but it is amazing to see how many new 'designer' homes there are in all parts of Australia with little or no eaves or shading of the windows.

Once we have the sun off the glass, if the climate is such that the interior of the house is still uncomfortable warm and the occupants require lower temperatures than what can be achieved via passive means (that's most of us, unfortunately) the airconditioner gets switched on, and creates a large temperature differential between inside and outside. This is the point at which insulated windows start to pay their way. The cool air inside the house is thermally isolated from the warm air outside the house because their is no direct connection between the glass cooled by the airconditioner and the glass heated by the outside air. Any single-pane glass window will act a thermal hole in the wall. Just put your hand on the window for confirmation. The same principle occurs in reverse when you heat your home in winter.

Low-e glass is a great development, but it is not an insulator. It helps to reduce transmission of heat by radiation, and it's a good option for doing _something_ about those designer houses. A better option would be to say no and find a place with some roof overhang.

woodbe.

I realise that it's a complicated subject with as many variables but -
Not everyone in Aus lives in a 'hot' climate.
Windows should be 'shaded' taking into account the climate zone and the orientation of the window.
[thats meant to be constructive not harsh]

Hi Peter,

Heck yes, I was specifically talking about the hot climate scenario, and I guess I dribbled off into the cold climate scenario with the window insulation as well.

Here in Adelaide, the recommendation is to allow winter sun through north-facing windows, and shade it from all windows in summer. That's a bit hard for us, we would have to cut holes in a wall to achieve north facing windows at all...

Interestingly, even here we have substantial heating needs if we are to maintain a pleasant indoor temperature during winter, so even though we get our fair share of hot weather, we have two energy use peaks per year, and the higher one is during winter. We really have to put measures in place that accommodate both extremes. Variable shading for east and west facing glass to allow the sun in during winter, and suitable insulated windows to trap it inside once it gets there are on the agenda for us.

No harshness taken. Try harder

woodbe.

g,day new here. Low e glass, been reading replies,curious to know, does any anyone know how it cuts heat transmission

maca

[in simple terms]Metal filings reflect the heat back into the room.