Yep. Foil is great and keeping heat out but not as good at keeping heat in. For that you would need a vacuum. Now I need to find a Thermos sized house.
Browse Forums Heating, Cooling & Insulation Re: Cost of perfect insulation??! 21Apr 13, 2009 6:11 pm ed @ EcoClassic Reflective foils would come close to stopping radiant heat... Just like a Thermos... Yep. Foil is great and keeping heat out but not as good at keeping heat in. For that you would need a vacuum. Now I need to find a Thermos sized house. Re: Cost of perfect insulation??! 22Apr 13, 2009 7:23 pm dymonite69 ed @ EcoClassic Reflective foils would come close to stopping radiant heat... Just like a Thermos... Yep. Foil is great and keeping heat out but not as good at keeping heat in. For that you would need a vacuum. Now I need to find a Thermos sized house. If you look inside a Thermos - you will find both surfaces - the one facing out and the one facing in are silvered... because they work in both directions - they don't know you see... and how would the silver know in which direction the heat is moving? "ECOECO" At 'EcoEco', we design windows, we design the best windows, we do it for you, so that when you’re happy we are happy. Tel. 1800 326 326 Re: Cost of perfect insulation??! 23Apr 13, 2009 9:05 pm ed @ EcoClassic dymonite69 ed @ EcoClassic Reflective foils would come close to stopping radiant heat... Just like a Thermos... Yep. Foil is great and keeping heat out but not as good at keeping heat in. For that you would need a vacuum. Now I need to find a Thermos sized house. If you look inside a Thermos - you will find both surfaces - the one facing out and the one facing in are silvered... because they work in both directions - they don't know you see... and how would the silver know in which direction the heat is moving? Not disputing this. Foil blocks radiant heat in both directions. In fact you don't even need two reflective surfaces. One is adequate. However, during winter the main source of heat loss is conducted and convected heat (with a smaller contribution from radiant heat). The opposite is true on a hot summer day where the main heat load is from solar radiation. If you just used foil to keep warm, you would be sadly disappointed. Batts (or a vacuum as you suggest) is the most effective way of keeping warmth in. Here is an analogy - what would you sleep in on the top of Mt Everest? A foil blanket or a nice thick fluffy sleeping bag. However, firefighters in the US have had their lives saved simply by entering a portable foil tent when a fire-front passes. People can survive temporary high air temperatures, but the foil reflects away the fatally intense radiant heat. Re: Cost of perfect insulation??! 24Apr 14, 2009 8:59 am dymonite69 Not disputing this. Foil blocks radiant heat in both directions. In fact you don't even need two reflective surfaces. One is adequate. However, during winter the main source of heat loss is conducted and convected heat (with a smaller contribution from radiant heat). The opposite is true on a hot summer day where the main heat load is from solar radiation. If you just used foil to keep warm, you would be sadly disappointed. Batts (or a vacuum as you suggest) is the most effective way of keeping warmth in. Here is an analogy - what would you sleep in on the top of Mt Everest? A foil blanket or a nice thick fluffy sleeping bag. However, firefighters in the US have had their lives saved simply by entering a portable foil tent when a fire-front passes. People can survive temporary high air temperatures, but the foil reflects away the fatally intense radiant heat. Gosh - you take every opportunity to lecture.... that's after you have checked your data... come on - you are just repeating what I said... Ed "ECOECO" At 'EcoEco', we design windows, we design the best windows, we do it for you, so that when you’re happy we are happy. Tel. 1800 326 326 Re: Cost of perfect insulation??! 25Apr 14, 2009 9:01 am dymonite69 Not disputing this. Foil blocks radiant heat in both directions. In fact you don't even need two reflective surfaces. One is adequate. However, during winter the main source of heat loss is conducted and convected heat (with a smaller contribution from radiant heat). The opposite is true on a hot summer day where the main heat load is from solar radiation. If you just used foil to keep warm, you would be sadly disappointed. Batts (or a vacuum as you suggest) is the most effective way of keeping warmth in. Here is an analogy - what would you sleep in on the top of Mt Everest? A foil blanket or a nice thick fluffy sleeping bag. However, firefighters in the US have had their lives saved simply by entering a portable foil tent when a fire-front passes. People can survive temporary high air temperatures, but the foil reflects away the fatally intense radiant heat. Gosh - you take every opportunity to lecture.... that's after you have checked your data of course... come on - you are just repeating what I said... you said - it doesn't work so well keeping heat in... of course it does with radiant heat. Ed "ECOECO" At 'EcoEco', we design windows, we design the best windows, we do it for you, so that when you’re happy we are happy. Tel. 1800 326 326 Re: Cost of perfect insulation??! 26Apr 14, 2009 9:03 am dymonite69 Not disputing this. Foil blocks radiant heat in both directions. In fact you don't even need two reflective surfaces. One is adequate. However, during winter the main source of heat loss is conducted and convected heat (with a smaller contribution from radiant heat). The opposite is true on a hot summer day where the main heat load is from solar radiation. If you just used foil to keep warm, you would be sadly disappointed. Batts (or a vacuum as you suggest) is the most effective way of keeping warmth in. Here is an analogy - what would you sleep in on the top of Mt Everest? A foil blanket or a nice thick fluffy sleeping bag. However, firefighters in the US have had their lives saved simply by entering a portable foil tent when a fire-front passes. People can survive temporary high air temperatures, but the foil reflects away the fatally intense radiant heat. Gosh - you take every opportunity to lecture.... that's after you have checked your data of course... come on - you are just repeating what I said... you said - it doesn't work so well keeping heat in... of course it does with radiant heat. But to work equally well in both directions it needs one small change to how it is currently supplied... do you know what it is? Ed "ECOECO" At 'EcoEco', we design windows, we design the best windows, we do it for you, so that when you’re happy we are happy. Tel. 1800 326 326 Re: Cost of perfect insulation??! 27Apr 14, 2009 10:51 am ed @ EcoClassic to work equally well in both directions it needs one small change to how it is currently supplied... do you know what it is? Well what do you mean by this? For windows or walls? To block exiting radiant heat? To block exiting conducted/convected heat? ed @ EcoClassic Gosh - you take every opportunity to lecture I am happy to sit in on your lecture. Just two academics jousting ed @ EcoClassic you are just repeating what I said Actually I will repeat you one more time since you have already given the answer: viewtopic.php?p=152300#p152300 and also from the AWA website: http://www.awa.org.au/documents/HowComf ... sWorks.pdf Low-e windows should block about 85 % of exiting long wave radiated heat energy from the building interior. However, a large proportion of loss is also conducted out The best window solution to block both conducted heat exiting would be double glazing combined with low-e. EcoClassic, So here is my lecture: I have nothing against the technological improvements in glazing. They offer a large degree of flexibility for the thoughtful home designer. But as in most things in good design, equal attention to other elements need to be addressed. Good passive solar design allows these windows to be used to their greatest advantage with respect to orientation +/- shading +/- window coverings. What concerns me with the building codes (and a few design manuals) are their over-simplified instructions to achieve a 5 star home whether it be insulation or otherwise. There are optimal combinations, arrangements, installations and usage that combines these things in the best way. I am sure your company gives thoughtful advice based on a customers plans about what kind of windows go where. However, there are probably equally unscrupulous operators out there who will just sell a product. Re: Cost of perfect insulation??! 28Apr 14, 2009 1:39 pm dymonite69 ed @ EcoClassic to work equally well in both directions it needs one small change to how it is currently supplied... do you know what it is? Well what do you mean by this? For windows or walls? To block exiting radiant heat? To block exiting conducted/convected heat? I meant the opposite of what you mean by this... dymonite69 ed @ EcoClassic Reflective foils would come close to stopping radiant heat... Just like a Thermos... Yep. Foil is great and keeping heat out but not as good at keeping heat in. For that you would need a vacuum. Now I need to find a Thermos sized house. dymonite69 ed @ EcoClassic you are just repeating what I said Actually I will repeat you one more time since you have already given the answer: viewtopic.php?p=152300#p152300 and also from the AWA website: http://www.awa.org.au/documents/HowComf ... sWorks.pdf Low-e windows should block about 85 % of exiting long wave radiated heat energy from the building interior. However, a large proportion of loss is also conducted out The best window solution to block both conducted heat exiting would be double glazing combined with low-e. Low-E blocks radiant heat, double glazing blocks conducted heat. You can have Low-E on surface 2 of a d/g unit and it will block radiant heat from exiting the building (surface 3 to block radiant heat coming in). I hear you... but no matter what, windows are the greatest energy leak in any home and double glazing would reduce that by around 2/3. That's without sales spin, just a fact. The answer to my question is...
Ed "ECOECO" At 'EcoEco', we design windows, we design the best windows, we do it for you, so that when you’re happy we are happy. Tel. 1800 326 326 Re: Cost of perfect insulation??! 29Apr 14, 2009 4:16 pm ed @ EcoClassic no matter what, windows are the greatest energy leak in any home It would be incorrect to say windows are just an energy liability. Since they allow radiant heat (and light) to pass in easily they can be a portal for useful energy gain (something that a wall cannot achieve) Energy efficient design generally is dependent on some form of glazing. By capturing winter sun (1 bar radiator per m2) this can provide useful warming energy that lasts not only during the day but for a large part of the evening as well. Of course in summer, direct sunlight is what you will try to avoid. Passive solar is a way of achieving both goals with the same window. Re: Cost of perfect insulation??! 30Apr 14, 2009 4:25 pm ed @ EcoClassic If the foil is coated on one side it reduces the efficacy of that side by close to 100%. Coated foils are used for the convenience of trades and to allow the builder to advertise Actually the less reflective coating doesn't alter the behaviour of the foil barrier. The critical thing is to have the shiny side facing an air gap. It doesn't matter if shiny is facing outwards or inwards. This is counter intuitive to most lay people but it relies on a simple law of physics. High reflectivity = Low emissivity. The analogy can be seen in a stainless steel teapot. You will note the shiniest side face outwards. Fill the pot with boiling water. Hold your hand a few centimetres away from the pot. You will notice that little heat (emitting) is radiating away from it. Although the metal is very hot to touch, the shiny surface prevents radiant heat from escaping the surface. Transferring the theory to building foil. The hot sun beats on the wall or roof of the house. The material heats up and re-radiates the energy inwards and onto the coated foil beneath. The foil in turn heats up but the shiny side facing inward can't 'release' the heat into the house. As the foil heat us it re-radiates the heat from the coated side back outwards again. It appears to 'reflect' radiant heat. The recommendation accords with the University of Florida's consumer recommendation: http://www.fsec.ucf.edu/en/publications ... -37-88.pdf Re: Cost of perfect insulation??! 32Apr 14, 2009 6:01 pm Just heard from my architect. He claims that going over R3.5 for the ceiling and R2 for the walls is pointless, as it makes very little difference. Sisalation's OK too, no need for Glareshield and Anticon55's sufficient. Chris My father rode a camel, I drive a car, my son flies in a jetliner, his son will ride a camel.Saudi saying Re: Cost of perfect insulation??! 33Apr 14, 2009 6:15 pm kristofw Sisalation's OK too I am glad you got some foil. I had a colleague have a house designed by an "eco-architect" and they forgot to put a radiant barrier on the west bedroom which has caused it to overheat during summer. Re: Cost of perfect insulation??! 34Apr 19, 2009 8:46 pm Hi Dymo, What is a radiant barrier? is it sarking material? Re: Cost of perfect insulation??! 35Apr 19, 2009 9:20 pm laksaginta Hi Dymo, What is a radiant barrier? Anything that reflects away thermal radiation. All polished metal surfaces can do this. Technically sarking is anything which acts as an air or moisture barrier and can be as simple as a sheet of polypropylene. Normally the two functions are combined sarking+radiant barrier = Sisalation (and the like) Re: Cost of perfect insulation??! 36Apr 19, 2009 9:48 pm Hi kristofw Where are you getting your windows again? Are they double glazed? How much were they, if you dont mind me asking? Re: Cost of perfect insulation??! 37Apr 19, 2009 9:50 pm kristofw Ceiling: 171m2, R5 Pink Batts - $2530 External Walls: 145m2, CSR Rockwool Batts - $2700 External Walls Wrap: 145m2, Air-Cell Glareshield - $1276 Internal Walls: 72m2, Tontine Accoustic Polyester Batts - $580 Colorbond Rood Blanket: 220m2, Bradford Anticon 100 - $2365 Total: $9451! Ouch!!!! It's not easy to be green WOW. That is sooo expensive. Are you really getting all those things? Re: Cost of perfect insulation??! 38Apr 19, 2009 11:27 pm gettingThere kristofw Ceiling: 171m2, R5 Pink Batts - $2530 External Walls: 145m2, CSR Rockwool Batts - $2700 External Walls Wrap: 145m2, Air-Cell Glareshield - $1276 Internal Walls: 72m2, Tontine Accoustic Polyester Batts - $580 Colorbond Rood Blanket: 220m2, Bradford Anticon 100 - $2365 Total: $9451! Ouch!!!! It's not easy to be green WOW. That is sooo expensive. Are you really getting all those things? R5 for ceiling PLUS Roof blanket is overkill for bulk insulation. It works only little better but for a lot more money. Unless you actually want to live in the roof space, you could just use plain foil under the metal roof for summer radiant control. The ceiling batts are more than adequate for winter heat loss. Same thing with external walls. You could just use foil instead of glareshield. Re: Cost of perfect insulation??! 39Apr 20, 2009 10:45 am Hi GettingThere, Quote: Where are you getting your windows again? Are they double glazed? How much were they, if you dont mind me asking? The windows're coming from Poland, by now they should be in the Indian Ocean. I've paid all costs on the Polish side, what remains is the delivery costs here. So far it's $A11,994.52. I expect to pay $1500 in port charges and handling costs here, possibly some quarantine costs and customs and GST on these 12K, $1800. All in all it'll cost me $15K for 37m2 of double glazed, argon filled windows with mozzie nets. The uPVC double glazed windows' price has been falling here, so I'm not sure if it's very good, good, or neutral. Quote: WOW. That is sooo expensive. Are you really getting all those things? kristofw Ceiling: 171m2, R5 Pink Batts - $2530 External Walls: 145m2, CSR Rockwool Batts - $2700 External Walls Wrap: 145m2, Air-Cell Glareshield - $1276 Internal Walls: 72m2, Tontine Accoustic Polyester Batts - $580 Colorbond Rood Blanket: 220m2, Bradford Anticon 100 - $2365 Total: $9451! Ouch!!!! It's not easy to be green On advice from my architect, which is the same as Dymonite's here, I'm opting for the lower ratings, which should be satisfactory: Ceiling - R4, Walls - R2, Sisalation for membrane. Chris My father rode a camel, I drive a car, my son flies in a jetliner, his son will ride a camel.Saudi saying Re: Cost of perfect insulation??! 40Apr 20, 2009 10:50 am kristofw Hi GettingThere, Quote: Where are you getting your windows again? Are they double glazed? How much were they, if you dont mind me asking? The windows're coming from Poland, by now they should be in the Indian Ocean. I've paid all costs on the Polish side, what remains is the delivery costs here. So far it's $A11,994.52. I expect to pay $1500 in port charges and handling costs here, possibly some quarantine costs and customs and GST on these 12K, $1800. All in all it'll cost me $15K for 37m2 of double glazed, argon filled windows with mozzie nets. The uPVC double glazed windows' price has been falling here, so I'm not sure if it's very good, good, or neutral. Quote: WOW. That is sooo expensive. Are you really getting all those things? kristofw Ceiling: 171m2, R5 Pink Batts - $2530 External Walls: 145m2, CSR Rockwool Batts - $2700 External Walls Wrap: 145m2, Air-Cell Glareshield - $1276 Internal Walls: 72m2, Tontine Accoustic Polyester Batts - $580 Colorbond Rood Blanket: 220m2, Bradford Anticon 100 - $2365 Total: $9451! Ouch!!!! It's not easy to be green On advice from my architect, which is the same as Dymonite's here, I'm opting for the lower ratings, which should be satisfactory: Ceiling - R4, Walls - R2, Sisalation for membrane. Chris Wow! All the way from Poland! Let me know how it all goes once they are all in. How does that compare to what it would have cost you if you bought it from Australia? We used a smaller qld builder who went bankrupt about 12 months after completion of ours. It was a shame as they were good and relatively cheap and I would have used… 3 4668 Hey guys building a new place through a volume builder and just wondering if i should complain to the site supervisor as we just had plasterboard installed. Looks like… 0 11255 1000000% definitely add insulation. I have in my home and it makes a big difference minimising sound transfer. Insulation is pretty cheap and definitely worth it 2 6174 |