Browse Forums Eco Living 1 Aug 17, 2008 3:51 pm Hi there!
I have just been reading up on thermal mass and icf's and am now a bit confused. From what i have read, it seems thermal mass must be teamed with (external?) insulation to achieve is best possible performance. Which brings me to..do ICFs require extra insulation, or is the insulation to the outer and inner face of the wall adequate. If anyone can clear this up it would be greatly appreciated!! Re: Insulation to Thermall Mass (in particual ICF walls) 2Aug 17, 2008 5:12 pm Hi leah,
I don't know much about ICF's but from what I can gather the concrete is inside an insulated layer on the outside and inside, correct?? If this is so then, no - the thermal mass of the concrete is not available to act as a heat sink for a passive solar design. For passive solar design to work, the thermal mass needs to be located within the insulated shell of the house. This could be in the form of an exposed concrete floor or solid brick internal walls. The following link explains it much better than I can http://www.yourhome.gov.au/technical/fs49.html Goodluck 'chelle We have a hand-over date...15/10...but I won't hold my breath! http://people-in-glass-houses.blogspot.com/ Re: Insulation to Thermall Mass (in particual ICF walls) 3Aug 17, 2008 5:38 pm Hi,
insulation belongs to the outside if somehow possible. No point to have thermal mass out side the insulation envelope. Re: Insulation to Thermall Mass (in particual ICF walls) 4Aug 17, 2008 5:39 pm Hi,
insulation belongs to the outside if somehow possible. No point to have thermal mass out side the insulation envelope. Re: Insulation to Thermall Mass (in particual ICF walls) 5Aug 17, 2008 7:14 pm thankyou both for the reply
yes, an icf is insulated by polstrene on both sides, which i guess is why i posted my question. from what i had read all on thermall insulation (oh, thanks for that link by the way, that was one of the web pages i was reading from!) it seemed it had to be insulated from the outside (which this product does...but it also insulates from the inside! hence my conundrum) but i found this case study: http://www.yourhome.gov.au/technical/pubs/fs811.pdf it seems as though it is still effective (though obviously not as much as reverse brick veneer) and it's effective in a similar climate zone im looking at. It seems the extra insulation releases the heat much more slowly and is a "benefit in prolonged sunless winter periods and summer heatwaves" PHEW! Re: Insulation to Thermall Mass (in particual ICF walls) 6Aug 17, 2008 7:52 pm back again. ok, so here is a more concise explanation. one that i could get my head around it helped me so i hope it helps you. the only question now is....APART FROM REVERSE BRICK, HOW CAN I INSULATE A CONCRETE (BLOCK) WALL ON THE EXTERIOR!!?
http://www.thermalwall.com/comparative-analysis.html (DAMN, couldnt quite copy the text, so here is the link) Re: Insulation to Thermall Mass (in particual ICF walls) 7Aug 17, 2008 9:20 pm Leah =basically you need a mass of concrete etc to hold the heat - and something to stop it changing. so insulating it (on the outside) is a way of achieving this.
Steve Re: Insulation to Thermall Mass (in particual ICF walls) 8Aug 17, 2008 9:46 pm Yes you need insulation and thermal mass. Together these smooth out temperature variations. Only the thermal mass on the inside of the insulation counts towards smoothing out temperature swings.
Assuming no artificial heating or cooling and no sunlight entering a room a very high thermal mass and very high thermal insulation would result in a internal temperature that is roughly the average of the daily temperature. If you double the thermal mass you can half the thermal insulation to get the sam effect. It's very hard to double insulation (you basically have to double the insulation thickness), but it's relatively easy to increase thermal mass by 100 by changing from gyprock walls to brick. That is, put some insulation up but there's no need to get too carried away, but try to get large thermal mass inside. Now if you want to shift the temperature from roughly the daily average you can do the following. To move the temperature up, allow low winter sun to enter from the north. To move the temperature down, ventilate during summer nights and lock up the house during the day. The effect can last for several days if you have high thermal insulation and mass. Demolition August 2009, Construction Started September 2009, Completed December 2010 Re: Insulation to Thermall Mass (in particual ICF walls) 9Aug 18, 2008 9:43 am leah back again. ok, so here is a more concise explanation. one that i could get my head around it helped me so i hope it helps you. the only question now is....APART FROM REVERSE BRICK, HOW CAN I INSULATE A CONCRETE (BLOCK) WALL ON THE EXTERIOR!!? So are you not going with ICFs anymore?? To insulate a concrete wall on the outside you could try those polystyrene panels that can be stuck on the outside and then rendered over. From Your Home... Single skin high mass walls such as concrete block.....can have their thermal performance radically improved by installing insulation on the wall exterior. The simplest method is to use polystyrene board with an external render, or batts fixed between battens at around 600mm centres, covered with a waterproof cladding. Do you have any plans or ideas of what you want to do? Are you bulding from scratch or trying to improve an existing house? Cheers 'chelle We have a hand-over date...15/10...but I won't hold my breath! http://people-in-glass-houses.blogspot.com/ Re: Insulation to Thermall Mass (in particual ICF walls) 10Aug 18, 2008 11:28 am Brilliant!! You have all been so helpful.
Yes, we will be heating the area with north facing windows, which will we adequately shaded in summer. The room will also be teamed with a polished concrete floor. We will be able to cross ventilate in summer with a series of openanble doors and sash (or louvered!) windows. It will be a brand new house: floor plan practically finalised, just need to figure out the benefits we can now achieve from building materials. One thing: The wall we are looking at building from ICF (or insulated concrete block, still need to research!) will be along the west external wall. I am still considering using it for South, East and North, but becasue this will be a beach house i want to achieve the traditional beach house look (that being weatherboard, light weight cladding). Obviously with it only along the west wall it wont be as effective as if all walls were concrete, but will this still have some affect? (assuming all the lightweight walls are insulated at a high r value) So many questions!!! Sorry everyone Re: Insulation to Thermall Mass (in particual ICF walls) 12Aug 30, 2008 4:57 pm has anyone on here actually built with ICF as yet?
i am struggling to find any other outside unbiased information regarding any aussie made products -Nathan 2nd-Fix | Blog Building with Desyn Homes previously with the insolvent [url=https://www.facebook.com/7NewsAdelaide/videos/1162546323776021/]Endeavour Homes[/url] Re: Insulation to Thermall Mass (in particual ICF walls) 13Nov 01, 2008 4:15 pm 'chelle Hi leah, I don't know much about ICF's but from what I can gather the concrete is inside an insulated layer on the outside and inside, correct?? More eco-rubbish being peddled. Oakridge National Laboratory (ORNL) has modeled this already e.g. Mass inside, in the middle and outside. Mass inside/thermal insulation outside is best. Mass in the middle is pointless, expensive and wasteful. Search their site to find the study. Re: Insulation to Thermall Mass (in particual ICF walls) 14Mar 13, 2009 11:53 pm digging up an old post, anyone on here built or is considering building with it yet? do i have to be the first?
-Nathan 2nd-Fix | Blog Building with Desyn Homes previously with the insolvent [url=https://www.facebook.com/7NewsAdelaide/videos/1162546323776021/]Endeavour Homes[/url] Re: Insulation to Thermall Mass (in particual ICF walls) 15Mar 14, 2009 7:51 am dymonite69 Oakridge National Laboratory (ORNL) has modeled this already e.g. Mass inside, in the middle and outside. Mass inside/thermal insulation outside is best. Mass in the middle is pointless, expensive and wasteful. Search their site to find the study. Here is the paper and conclusion from sixteen different configurations of insulation and mass: "Comparative analysis of sixteen different material configurations showed that the most effective wall assembly was the wall with thermal mass (concrete) applied in good contact with the interior of the building. Walls where the insulation material was concentrated on the interior side, performed much worse. Wall configurations with the concrete wall core and insulation placed on both sides of the wall performed slightly better, however, their performance was significantly worse than walls containing foam core and concrete shells on both sides. " http://www.ornl.gov/sci/roofs+walls/res ... index.html The only advantage of ICF is due to ease of construction for a monolithic pour. The foam provides insulation. There are little thermal mass benefits from the concrete for heating. The best combination is insulation on the outside to keep the warmth of the thermal mass exposed on the inside. Re: Insulation to Thermall Mass (in particual ICF walls) 16Mar 14, 2009 10:39 am When it comes to thermal performance and low maintenance, you can't beat a full brick house. It's a proven building method and allows you to have a suspended concrete slab between floors (read large thermal mass).
Don't get to caught up in insulation. Sure, put some in, but you can get more bang for buck with large thermal mass (internal brick walls and concrete slab). This will smooth out daily temperature variations. Then you can have some north facing windows to increase the temperature in winter and night-time ventilation to cool the house in summer. Now, even though you're only warming during winter days and summer nights, the large thermal mass on the inside (and some insualtion on the outside) means that the benefit carries through to the next day. With a good design as detailed above you can have a house that's comfortable all year round (18 C to 28 C) without any air conditioner or heater. With a little bit of low energy additions, you can get this range down to 20 C to 26 C. Demolition August 2009, Construction Started September 2009, Completed December 2010 Re: Insulation to Thermall Mass (in particual ICF walls) 17Mar 14, 2009 3:46 pm Casa2 but you can get more bang for buck with large thermal mass (internal brick walls and concrete slab). With a good design as detailed above you can have a house that's comfortable all year round (18 C to 28 C) without any air conditioner or heater. I would suspect that brick-veneer with insulation or reverse brick veneer would still be cheaper than double brick Design is a key point. If there is too much direct summer sun shining on your internal brick then you will overheat and find it will be hard to shed it at night. Keep west and east sun off the internal walls and make sure the north is adequately shaded from the high-angled summer sun. The other consideration is the embodied energy of two brick layers. An alternative to get mass on the inside leaf would be to use Aerated concrete which also provides some insulation. This has less embodied energy, easy to erect and easy to attach fixings. Re: Insulation to Thermall Mass (in particual ICF walls) 18Mar 14, 2009 10:32 pm dymonite69 Casa2 but you can get more bang for buck with large thermal mass (internal brick walls and concrete slab). With a good design as detailed above you can have a house that's comfortable all year round (18 C to 28 C) without any air conditioner or heater. I would suspect that brick-veneer with insulation or reverse brick veneer would still be cheaper than double brick Design is a key point. If there is too much direct summer sun shining on your internal brick then you will overheat and find it will be hard to shed it at night. Keep west and east sun off the internal walls and make sure the north is adequately shaded from the high-angled summer sun. The other consideration is the embodied energy of two brick layers. An alternative to get mass on the inside leaf would be to use Aerated concrete which also provides some insulation. This has less embodied energy, easy to erect and easy to attach fixings. Although reverse brick veneer would be cheaper up front, when you take into consideration the ongoing maintenance of the external walls, you'll come up on top with brick on the outside. I wouldn't put aerated concrete on the inside. It takes up too much space and doesn't have the thermal mass of brick. Full brick can't be too expensive, it's standard in Western Australia. Demolition August 2009, Construction Started September 2009, Completed December 2010 Re: Insulation to Thermall Mass (in particual ICF walls) 19Mar 14, 2009 10:46 pm Casa2 Although reverse brick veneer would be cheaper up front, when you take into consideration the ongoing maintenance of the external walls, you'll come up on top with brick on the outside. I wouldn't put aerated concrete on the inside. It takes up too much space and doesn't have the thermal mass of brick. Full brick can't be too expensive, it's standard in Western Australia. As with most things the relative cost-benefits depends on various factors. RBV is a reasonable solution if you use a lightweight, waterproof cladding like Colourbond or Micro-orb. No real maintenance issue but it may not be everyones cup of tea. AAC how now been recognised as adequate as a single skin walling with enough combined thermal mass and insulation properties that provides a thermally comfortable home for a temperate climate. "The Building Code of Australia provides an AAC masonry Deemed to Comply building solution consisting of a 200mm thick AAC wall and finishes, which requires no additional R-value insulation in most Climatic Zones around Australia. Although the R-value is lower than a well insulated, timber-framed structure, the combination of thermal mass and thermal insulation properties can deliver savings in heating and cooling costs through the life of a home." http://www.yourhome.gov.au/technical/pubs/fs511.pdf I discuss this intriguing observation and theorise on why this would work on: http://forums.envirotalk.com.au/Keeping ... e=threaded I gather Double brick is very popular in WA and price competitive. Correct me if I am wrong but I don't think this is equally true for the Eastern States. Adelaide's reactive soil is very unforgiving to double brick. Re: Insulation to Thermall Mass (in particual ICF walls) 20Mar 15, 2009 12:38 pm FireFox has anyone on here actually built with ICF as yet? i am struggling to find any other outside unbiased information regarding any aussie made products -Nathan Hi Nathan We're in the same boat as you. Can't find anyone who has used Zego or any other insulating block. We questioned one builder about using it and he seemed very reluctant. Said there are major problems of supply and comunication with the companies marketing it. We were told that it has the best r values after straw bales so are keen to use it but we are getting no-where because no-one's interested. You may have to be the first. We'll see how you go!!! Good questions but the best answer will be obtained by visiting (ie: interviewing) a couple of house designers and/or builders and ask them. You may find it challenging to… 2 3234 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 11269 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 6191 |