1. MagTech Ultra
This brand does claim to source raw materials and make the panels in the US.
They say it’s zero VOC but it does not look like it has been tested. Under LEED it’s exempt from testing since it’s in the “Inherently Non-Emitting” category.
That means: “products that are inherently non-emitting sources of VOCs (stone, ceramic, powder-coated metals, plated or anodized metal, glass, concrete, clay brick, and unfinished or untreated solid wood flooring) are considered fully compliant without any VOC emissions testing if they do not include integral organic-based surface coatings, binders, or sealants.”
The HPD shows a number of undisclosed ingredients: 3 undisclosed inorganic fillers (probably minerals), an undisclosed hardener listed as non-hazardous, an undisclosed water reducer (listed as persistent, bioaccumulative and inherently toxic (PBiTH) to humans), and an undisclosed strengthening agent (non-hazardous).
ASTM test results confirm MagTech Ultra is non-combustible, Class A fire rated, and suitable for use in fire-rated wall assemblies.
Overall take on this brand: I don’t know how established they are. It is a good sign that they have documentation like the HPD. We know there is a toxin in there but we don’t know which one.
This brand has a lot less information on their site.
The SDS lists wood fiber as a component, and 0.2% undisclosed ingredients. On the website, they claim it’s zero VOC but they do not show any testing. Though if their ingredient list is accurate then that should be correct.
The website doesn’t mention where it is made. I called them and they didn’t know on the main inquiry line.
MagPanel® is UL 055 and ASTM-tested and A-rated.
They do claim to be made in the US.
There are proprietary additives not listed but they claim zero VOC.
It meets ASTM E-84, ASTM E-136-1
This brand has been around for a while, and that is a good thing in the MgO brand world. Many sensitive folks like this brand.
4. Huber Exacor, Formerly Extreme Green
This brand is only meat for subflooring and underlayment.
They provide a 10-year warranty. Huber is a major construction materials company so I would be most likely to look at this brand first.
Though they do not provide info on where it’s made and the VOCs. They say it’s manufactured in a quality-controlled environment audited by NTA and UL to maintain consistency. (So probably not made in America!)
I like this brand as it’s by Huber and it has specs and testing for this to be used as structural subfloor. Many companies have gone in and out of business with MgO in the last 10 years so I would prefer a big company like Huber.