Re: [papercreters] Portland VS Lime, CO2, etc...

Oh and bugs dont not like it.

Ken

John Annesley <John@AnnesleyPhoto.com> wrote:

I haven't made any strictly limecrete blocks or anything, but I have been using lime lately
with clay-and-paper plaster, and have come across some very interesting facts about lime
which I wasn't entirely aware of. Ken is quite correct that it inhibits mold and mildew. It
has a lot of other benefits, as well as detailed below. I got most of this info from a British
site about Lime, and there's a lot more on the site than the factoids listed below regarding
Lime VS Portland: http://www.strawbalefutures.org.uk/infolime.html

Lime mortars and plasters are:

Permeable. This means that vapour can pass through them at an almost imperceptible
level, which is a healthier option for inhabited buildings as it regulates humidity.
Flexible. Lime can move as the earth moves through changing seasons, without cracking
the structure or causing instability.
Weatherproof. Not waterproof, thus protecting the building without sealing it.
Not susceptible to frost. They do not freeze as they are not `wet', therefore do not require
foundations to be below the frost line.
Do not attract moisture.
Deal with moisture effectively. They can hold excess moisture from the atmosphere in
humid conditions e.g. in a shower, without becoming `wet' and then release it slowly back
as humidity drops.
Proven over centuries. The Romans used lime very effectively for many applications
including major engineering projects such as bridges, domes, suspended floors and
heated floor slabs. The earliest known use of lime is 4000 years ago.
Reduces green house gas effect. Over its lifetime, due to the cycle of lime changing from
limestone to quicklime and back to limestone again, most of the CO2 released during the
manufacturing process is re-absorbed, thus being close to carbon neutral.
On the other hand, cement is

Not permeable. Creates a sealed surface that does not allow vapour passage.
Rigid, induces cracking when expansion and contraction or settling are at hand.
Susceptible to frost. Will crack in very cold conditions and therefore if used in foundations,
needs to be in deep trenches that make contact with the warmth of the earth to avoid
problems associated with frost heave.
Attracts moisture. Other materials around cement need to be protected from it as it holds
water and can cause rot to develop.
Does not deal with moisture. Can cause condensation problems in bathrooms, kitchens,
bedrooms etc. as it does not regulate moisture.
Does not have a long history. It was invented in the mid 19th century and began to be
used extensively from 1930 onwards. We are seeing some major damp and durability
problems now, caused by the inappropriate use of cement from 50 or so years ago e.g.
collapse of cob walls re-plastered with cement, the need to re-inforce some motorway
bridges, excessive cracking in town houses leading to difficulty in re-selling.
Causes green house gas effect. The manufacture of cement is one of the major causes of
the green house gas effect globally as it releases tonnes of carbon dioxide into the
atmosphere.




Yahoo! Groups Links

<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/papercreters/

<*> Your email settings:
Individual Email | Traditional

<*> To change settings online go to:
http://groups.yahoo.com/group/papercreters/join
(Yahoo! ID required)

<*> To change settings via email:
mailto:papercreters-digest@yahoogroups.com
mailto:papercreters-fullfeatured@yahoogroups.com

<*> To unsubscribe from this group, send an email to:
papercreters-unsubscribe@yahoogroups.com

<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/

---

Building a website is a piece of cake.
Yahoo! Small Business gives you all the tools to get online. __._,_.___

SPONSORED LINKS

Home repair improvement	Papercrete	International building code
Home and gardens	2000 international building code

Your email settings: Individual Email|Traditional
Change settings via the Web (Yahoo! ID required)
Change settings via email: Switch delivery to Daily Digest | Switch to Fully Featured
Visit Your Group | Yahoo! Groups Terms of Use | Unsubscribe

__,_._,___