How Light Is Lightweight Concrete?

Since concrete and mortar are such versatile construction media, you can adjust the mix design of a lightweight concrete mix (any concrete mix) to have whichever properties you find desirable. This dynamic nature of concrete and cement allows you to adjust the weight of a given concrete mix simply by replacing the heavier aggregates, commonly sand and gravel, with lightweight or lighter weight aggregates. Some examples of common light weight aggregates used in lightweight concrete mixes are pumice stone, perlite, vermiculite, peat moss, sawdust, clay, shale, coral and even foam.
No matter what kind of lightweight aggregate you use, something that is almost universally true is that the lighter the concrete is, the weaker it will be. While there are many admixtures which can be used to increase strength of a concrete mix, lightweight mixes included, these would still be much weaker than even a generic full weight concrete mix. When you take away weight, you take away strength.
In this example video, we are able to make the following comparison:
Full weight mortar brick = 3.8 kg
4:1 perlite to cement brick = 1.37 kg
4:1 vermiculite cement brick = 1.5 kg
These numbers represent a rough estimate as to the relationship between full weight concrete and lightweight concrete. In these examples, the lightweight mix was between half to one-third the weight of the full weight concrete test block.
Referral links to products featured in Creating Concrete videos - As an Amazon Associate I earn from qualifying purchases
amzn.to/3vtmang - interlock stone mold
amzn.to/3VIEmDX - universal mold release
amzn.to/3TQ9e30 - silicone mold release
amzn.to/3J7Q2II - sonite sealing wax
amzn.to/4cDYz3T - Quikcrete red pigment
amzn.to/4cIlDOK - Quikcrete brown pigment
amzn.to/43EuVHL - Quikcrete charcoal pigment
amzn.to/3J0MLee - Quikcrete bonding adhesive (PVA)
amzn.to/3xlzwlW - Quikcrete bonding adhesive 4L (PVA)
amzn.to/4aiGGGg - Sika acrylic fortifier 4L
amzn.to/3vqjdUw - Drylok hydraulic cement
amzn.to/3J3aDhv - Bosch mortar mixing drill
amzn.to/4aiwQUS - 4.5" diamond cup wheel
amzn.to/4aisWvb - mortar mixing paddle whip
amzn.to/49nsDOq - Budget mortar mixer and paddle
amzn.to/4ayjR1z - Sea sponge set for texturing
amzn.to/3xvpE96 - Masonry / grout sponges
amzn.to/3TGrZ8H - Marshalltown margin trowel (rubber grip)
amzn.to/3VEhntP - Marshalltown margin trowel (wood grip)
amzn.to/3xujXbx - Marshalltown point trowel (rubber grip)
amzn.to/3TCp9Se - Marshalltown point trowel (wood grip)
amzn.to/4ale5A4 - Marshalltown 12" square trowel
amzn.to/4aEsUNI - 16" pool trowel set
amzn.to/43H3cpO - powdered concrete pigments
amzn.to/4avz2Is - fine sponge float
amzn.to/4cFsYPi - 5 gallon mixing bucket
amzn.to/4cyIKeG - bulk acrylic paint set
amzn.to/4aB9oBU - airbrush and compressor kit
amzn.to/3U29Y6c - high range water reducer
amzn.to/3TGModV - fiberglass reinforcement 3/4" strands
amzn.to/4cEd87w - alkalai resistant chopped glass fibers 3/4"
amzn.to/3J0YzNR - perlite 4 cubic foot bag (coarse)
amzn.to/3xiCYxI - vermiculite 4 cubic foot bag (coarse)
amzn.to/43H2xV8 - Aircrete FM-160 liquid foam maker
amzn.to/4aHPFk9 - RTV 100% silicone (10 pack)
amzn.to/3VKbWcS - Smooth-On Vytaflex 30 urethane rubber
amzn.to/3xiEhg6 - Smooth-On skin safe liquid silicone rubber
amzn.to/3VE04cj - slate texture skin
amzn.to/3J0QEAb - bluestone texture skin
amzn.to/3xmZfdR - basalt texture skin
amzn.to/4aFjSQE - Variable speed wet grinder step sanding kit
amzn.to/43I090s - 4.5 cubic foot cement barrel mixer 0.5hp
#CreatingConcrete #lightweightconcrete #diyconcrete #cement

[@cchemmes-seeseeart3948]

I heard of some people adding grated up styrofoam. What's your thoughts on that?

[@creatingconcrete]

I prefer perlite as it will absorb some water which is important in creating a bond with the cement within the mix. Plus perlite is easy to come by and not all that expensive. But COULD you use ground up styrofoam? Certainly. It would work, but maybe not the best overall option given other lightweight aggregate options.

[@cchemmes-seeseeart3948]

@@creatingconcrete Thanks for sharing your experience. It is tremendously appreciated.