slits/slots on the side of concrete buildings WTF

[infinity11]

they must be for ventialtion or condensation but not sure

some thai concrete wall have air slits
one looks like 2 rows of 4 bricks
each brick has 4 slits or slots

looks like some critters can find their way in
maybe mosqyitos, and spiders for sure
these bricks have no screen(s)

what exactly is the point or purpose if the building has windows?

[infinity11]

Hot air interior pressure release valve for enlosed space?

[krisb]

Something like this...

Ventilation.

[wayned]

Ventilation, usually in bathroom and kitchen areas. Everybody doesn't have air conditioning and exhaust fans!

[krisb]

Have seen it used in restraurant kitchen windows before. Bit hard to stomach that was.

[infinity11]

Something like this...

Ventilation.

NO

much smaller

[wayned]

If they are the horizontal slots , either 2 or 4 per bock, cut/made at a 45 degree angle to keep blowing rain out, they are used for ventilation in non air conditioned kitchens and bathrooms.

[somchaismith]

When they make those concrete homes, I know that they are made of house bricks with a layer of concrete over their outsides . I've always wondered when they lay the concrete what holds the concrete in place while it's drying?

[fasteddie]

Let the farts out?

[johnnyk]

When they make those concrete homes, I know that they are made of house bricks with a layer of concrete over their outsides . I've always wondered when they lay the concrete what holds the concrete in place while it's dryinhg?

Cement and concrete are not the same.

Cement is an ingredient of concrete which is basically cement + aggregate (sand and/or stones).

Cement isn't very strong on its own so is not suitable for load- bearing.

Concrete is used for structural strength as in foundations, bridge supports etc. The pillars holding up the BTS guideway are concrete, as an example.

To coat/render exteriors lime is often added to cement because it breathes allowing moisture to escape.

Cement bonds naturally to stone or brick unless it is mixed too loose/wet then it can't hold. Cement and concrete will not bond to wood which is why wood forms are used when pouring.

Edited December 30, 2013 by johnnyk

[marko kok prong]

When they make those concrete homes, I know that they are made of house bricks with a layer of concrete over their outsides . I've always wondered when they lay the concrete what holds the concrete in place while it's drying?

not sure if they use it here but when rendering in Australia,a bonding agent is added bondcrete was one i used to use,this gives the render a nice creamy constituency,and really helps it adhere to verticle surfaces,but it is fairly expensive,can't say as i have seen it used here.

[trogers]

They are called "Ventilation Blocks". They provide natural ventilation while serving as a secure wall and privacy. Commonly used in Thai outhouses and stores.

[Guitar God]

These things? I think they're there to let the lizards in and out.

[donx]

My in-law's house has them in all of the rooms. Funny thing was when my brother-in-law added an addition for his family, the slits were installed the wrong way such that the upper opening of the 45 degree angle pointed outside which meant that rain came into his part of house easily. They ended up just filling in all of those slits with mortar or something similar.