Cementitious foam insulation

{{Short description|Cement-based thermal and acoustic insulation}}Cementitious foam insulation is a cement-based thermal and acoustic insulation, with an R-value similar to that of fiberglass. It is installed as a foam with a consistency like shaving cream, or as pre-cast slabs.{{Cite web |url=http://www.induceramic.com/industrial-ceramic-product/ceramic-foam-insulation/foam-cement-insulation-board |title=Foam cement insulation board - Industrial Ceramics |access-date=2016-08-17 |archive-date=2016-10-07 |archive-url=https://web.archive.org/web/20161007201831/http://www.induceramic.com/industrial-ceramic-product/ceramic-foam-insulation/foam-cement-insulation-board |url-status=dead }} The current cost is similar to that of polyurethane foams.{{Cite web| title = Insulation Materials |author=Department of Energy| accessdate = 2016-08-17| url = http://energy.gov/energysaver/insulation-materials}}

Unlike many foam-in-place polyurethane foams, it is nonflammable and non-toxic. As it is water-based, it offgasses water vapour while curing, requiring ventilation and in some cases a dehumidifier. It cures more slowly than organic foams. However, it does not offgas volatile organic compounds as many organic foams do. Like cement, it is water-soluble until cured, but after curing it is water-resistant,{{Cite web|url=http://www.myhomescience.com/cementitious-foam-insulation-gets-second-look/|title=Cementitious Foam Insulation Gets a Second Look|date=2 November 2013}} but water-permeable.{{cite web

| url=http://www.mah.gov.on.ca/Asset9386.aspx?method=1

| title=Ruling No. 10-05-1241 Application No. B-2009-42

| publisher=Ontario Ministry of Municipal Affairs and Housing, Building Code Commission

| access-date=2016-08-17

| archive-date=2018-06-26

| archive-url=https://web.archive.org/web/20180626203354/http://www.mah.gov.on.ca/Asset9386.aspx?method=1

| url-status=dead

}}

It does not expand on setting, but may shrink slightly in open cavities. Structurally, it does not resemble concrete; at the low densities that make it well-insulating, it is quite fragile. It can be crumbled away to re-expose wiring or pipes, making a pile of grey powder. Also unlike concrete, it is quite lightweight.

It is not a new product, having been around for some decades, but exclusive rights to an established cementitious foam product have recently been purchased by a company that has been giving it more publicity.