Tag Archives: materials

Insulation Stuff (BDCS)

Posted on by

LOOSE FILL

 :)  :(
Cellulose High recycle content
Low embodied energy
Cotton High recycle content
Low embodied energy
Fiberglass
Perlite
Vermiculite Might contain asbestos
Plastic Fiber

BOARD

 :)  :(
EPS Not ozone-depleting
Flexible		 High embodied energy
XPS High R-value
High compressive strength
High resistance to water absorption		 Ozone-depleting
Expensive
Polyiso Not ozone-depleting
Recycled content		 High embodied energy
Polyurethane Not ozone-depleting
High R-value		 Expensive

SPRAYED

 :)  :(
Sprayed Polyurethane
(Close Cell, High Density)		 High R-value Ozone-depleting
 Sprayed Polyurethane
(Open Cell, Low Density)		 Not Ozone-depleting Low R-value
 Icynene (Low Density) Good for retrofitting
Advertisement

Difference between Laitance & Efflorescence

Posted on by

Laitance and efflorescence are really two completely different things, but they are both white, powdery substances, which can be confusing.

In short, laitance is formed when there’s too much water in the concrete mix, while efflorescence is the deposit on masonry surfaces caused by soluble salts in the units or in the mortar.

Laitance can be avoided by controlling the amount of water in the concrete mix. Efflorescence can be prevented, or at least minimized, by selecting materials free of harmful salts and by preventing water from penetrating the masonry. This may be accomplished by the use of solid and tight mortar joints, capped walls, effective flashing, and adequate weather protection of the masonry during construction.

Both laitance and efflorescence can present both cosmetic AND structural problems.

read more:
http://en.wikipedia.org/wiki/Efflorescence
http://www.concreteconstruction.net/concrete-articles/meaning-of-laitance.aspx