The best attic insulation for your needs may be found here.
Here are some more kinds of eco-friendly insulation available today.
You will have to check your local stores to find out if any of these options are available to you locally. Some can be ordered on-line, of course. It is also worth consulting your authorities to see what standards apply.
Here's a look at some of the best attic insulation products on the market today, including cellulose fibre and recycled plastic fibre. There is also a brief explanation of R values.
There are more choices described at Best attic insulation choices for green living
It is always good to check out any insulation material for its "R" value. This is a measure of how much heat it stops escaping (R for "resistance").
The job of insulation is to stop the transfer of heat from one area to another. As hot air expands, the warmer air in your home naturally will tend to expand into cooler areas (such as the attic), unless prevented by an insulating barrier. Also, surfaces may radiate heat and solid materials, such as floors and walls also conduct heat.
The R value of a material depends upon its thickness, as well as its qualities. The R value is based upon a factory measured "r factor" which is a constant for that material. When you insulate your attic or loft space you need to achieve the highest r value you can, which is why the depth of insulation is important.
Insulation needs to stop the three main kinds of heat transfer: radiation, conduction and convection. The main sources of heat loss in homes are conduction through solid materials such as walls, windows and roofs, and convection through gaps and doors. Some heat loss is also caused by radiation, too.
Reflective foil is good for reducing radiant heat loss but not much use for preventing conduction or convection.
Insulating material made of fibre, such as rockwool or cellulose is particularly good at reducing heat loss by conduction. It can be found as loose fill material or as semi-rigid "batts" or rolls.
Loose fill is particularly good for filling every available space. One disadvantage is that it may compact over time and become less effective.
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Cellulose fibre insulation products such as Warmcel (UK) have many advantages. the manufacturers claim that they are carbon neutral - or better! This means that carbon is actually locked up out of harms way when you use cellulose insulation. The cellulose in question is generally from recycled newspapers. This also means that the product is relatively cheap. The processing involves some "fluffing" to make the fibres expand to hold air.
It is treated to be fire-retardant and it is non toxic and there is no problems from irritation from skin contact. However, biocidal additives are used to make the material unappealing to insects, so it is as well to keep it off your skin. Usually some kind of borate is used.
Cellulose fibre insulation is usually used as a loose fill, so it is important that the space is reasonably free from disturbance.
This is a natural product which can be recycled by being composted or digested after use. It can also be incinerated.
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This is made from discarded plastic bottles - so manufacturers are doing us all a favour by keeping more plastics out of the oceans and other places they should not be!
85% of the product is recycled bottles and the other 15% is mainly polyester, which helps give it shape. It comes in rolls which expand as they are unpacked. It can be laid between joists and over floor areas in your attic without any special preparation beyond lifting cables or any flooring materials.
It's a good choice if you are adding to existing insulation. It has excellent insulating properties.
It is free from floating fibres so it is quite safe to use. You do not need to wear a mask when installing it - or any other special clothing.
It is guaranteed for up to 50 years and it has good sound insulating properties.
The main product in the UK is "Eco-Wool" which is available in major outlets, such as B and Q. This is not to be confused with EcoWool from New Zealand which is a merino wool based underlay.
See Best attic insulation for a greener home for more on using real wool for insulation.
This product scores well for price and cleanliness of use. The main problem that I've found is that many users report that it is hard to cut. You need some sharp kitchen scissors or even shears. The best technique is to compress it while you cut.
I've used it in my loft and found it to be reasonably easy to work with. I used gloves in case of skin irritation but used no other protective clothing. I used a kitchen knife to cut off sections as needed - that seemed to be easier than using scissors for the most part. It has certainly made a difference to the warmth of the house.
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Hemp has so many uses and this under-exploited material may well become a significant factor in home insulation, as well as clothing, nappies and nutrition.
Hemp can be mixed with lime to create a kind of concrete ("hempcrete") which has the strength of concrete and the insulating properties of hemp. A very useful hybrid! Hempcrete blocks are available in Europe for building. Hempcrete can also be used as a DIY product.
Hemp insulation for attics is entirely safe and you can install it without using any special protective clothing.
You can use hemp insulation between floors, between wall spaces and between rafters. Hemp insulation is treated with thermoplastic binders to prevent fibres being damaged by pests. This also makes it fire-resistant and it passes European safety standards.
Hemp batts are available from Greensteps.com in Britain and from Burdens Environmental.
This is a slightly unconventional approach to loft insulation, which may suit some people.
Clay can be made into small pellets which are sometimes used for many kinds of insulation. These expanded clay balls are very light and will float in water. They are about the size of marbles or slightly bigger.
They have great heat retaining properties and, like vermiculite and perlite they can be used where a loose fill is needed.
In Europe you can get them from Maxit and they are traded as Leca, Fibo and Arlita. These products are especially suitable for ground floor insulation and for flat roofs.
If you consider using them in your attic, take advice as to whether the ceiling is strong enough to support them as they will be a little heavier than the usual options.
Clay balls can also be incorporated into other materials such as mortars and lightweight blocks. I have heard of them being used in clay oven construction. They enable the exterior of the oven to remain relatively cool while the oven is hot inside.
Clay balls are very durable and they also have excellent sound insulating properties.
I've used clay balls in my attic and they have been very good. They have been in situ for about eight years now. We made sure that the ceiling was strong enough to support them and laid them between the joists to a depth of about 3 inches. I've added some eco wool on top of the flooring to create an overall higher R value.
I am not advocating clay balls for do-it-yourself insulation, or as the best attic insulation. I am simply drawing on my own experience of something which works quite well for us.
If you think about using clay balls in your home please do your due diligence to make sure that the product will be safe for you! For most people the regular methods such as recycled plastic eco-wool or cellulose will be the obvious choice to use.
One disadvantage of clay balls is that they will become heavy if allowed to get wet - so be sure that all plumbing is secure and you roof remains leak proof.
Whichever product you choose for your attic insulation, make sure that it will fulfill the needs that you and your family require from it. The best attic insulation is one that you are happy with and which saves you significant amounts of money - and which saves the planet from more damaging greenhouse gases.
Please note that any products recommended on this site are recommended in good faith. Not every product mentioned can be personally evaluated by the writer. The website owner derives financial benefit from affiliate links and advertising. Please see the disclosure page for more details.
More Best Attic Insulation for A Green Home? - copyright Greenfootsteps.com 2009
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