Cov hlau ua npuas ncauj yog cov qauv ntawm tes uas muaj cov khoom siv hlau (feem ntau yog txhuas) nrog cov roj uas muaj cov pores uas muaj feem ntau ntawm cov ntim. Cov pores tuaj yeem raug kaw (kaw-cell ua npuas ncauj) lossis sib txuas (qhib-cell ua npuas ncauj). Lub ntsiab yam ntxwv ntawm cov hlau foams yog ib tug siab porosity: feem ntau tsuas yog 5-25% ntawm lub ntim yog lub hauv paus hlau, ua cov ntaub ntawv ultralight. Lub zog ntawm cov khoom siv yog vim txoj cai square-cube.

Cov hlau nplaum feem ntau khaws qee lub cev ntawm lawv cov khoom siv hauv paus. Ua npuas ncauj ua los ntawm cov hlau tsis-flammable tseem tsis yog-flammable thiab feem ntau tuaj yeem siv los ua cov khoom siv hauv paus. Nws coefficient ntawm thermal expansion yog zoo sib xws thaum thermal conductivity yuav txo.

Txawm hais tias muaj ntau daim ntawv patents piav qhia txog cov qauv ua tau zoo, cov khoom siv sib xyaw, thiab cov txheej txheem tsim khoom, cov hlau foams tsis tuaj yeem suav tias yog cov khoom lag luam thiab cov neeg tsim khoom lag luam tsawg muaj nyob thoob ntiaj teb.