Magnesiacore FAQs

Which fillers and jointing products do I use?
Magnesiacore is a solid integral material without a separate face sheet. It is a finely porous dense sponge, but the edges are as hard and sound as the surface. Conventional fillers and jointing materials used with gypsum, cement and wood will work better on magnesiacore. Magnesiacore can supply accessory products developed and tested with our board material for many of the applications shown on our website.

The installation shown on our video results in strong joints and eliminates the need for tape, mesh or reinforcing materials over the board face, saving time and labor costs.

Pictures of filler applied & trimmed by cutting and scrapping with a blade before fully cured without taping or sanding.

What is coverage for stucco or floor-mix on Magnesiacore?
Magnesiacore provides a uniform surface for applying costly stucco type materials. A uniform smooth surface of magnesiacore as the base saves from five to ten times more stucco over a typical rough uneven handmade plaster/cement base.
Likewise, when laying ceramic floor tile over a magnesiacore base floor-mix can be applied using a 1/4" toothed spreader, using one quarter the amount of flooring adhesive of a 1/2" toothed spreader. This can extend floor coverage of a standard floor mix bag by up to four times, reducing costs substantially.

How to make a magnesiacore panel system with concealed fasteners?
Pictured below is a simple hidden fastener system for T&G panel walls. It utilizes two basic clips. One for the bottom panels which is a "J" shape metal that is secured to the structure and clips into the "Groove" of the bottom panel. The top metal strap is screwed onto the back of the magnesiacore panel and then onto the structure from the front. The next panel wedges its "Grooved" edge over the "Tongue" of the other panel bellow thus concealing the metal strap at the top.

How to do panels that interlock without T & G edges?
Adding metal, wood or plastic strips on the back of the board (with screws or glue), off-set from one another on adjacent boards, functions like T & G without routered edges. This is especially useful when using thin material that does not have the necessary thickness to groove, and also saves installation time when cutting on the jobsite.

Which side do I use?
Magnesiacore has a smooth side and a textured side. The smooth side is more for painting, thin coatings and mastic adhesives. The textured side is for heavier coatings, stucco, ceramic tiles, stone, brick and other finishes applied with thick paste cement sand based adhesives.
Either sides can be treated as finish material, ready to receive paint, sealers and adhesives to create more options. Either side can be sanded to obtain different sheens, roughness and effects.
Magnesiacore's textured side is rendered dimensionally uniform by machined scoring that provides a uniform surface for greater versatility of uses.
The fine uniform texture is also suitable for painting or can be left as a natural texture as pictured below.

What is recommended thickness for use as wallboard?
9mm (3/8") is recommended for a wall board in place of drywall. It provides a plaster hard wall that installs like drywall.

What is recommended thickness for ceramic tile floor backerboard?
We recommend 6mm (1/4") or 3mm (1/8") for laminating over existing plywood sub-flooring, floor boards or over the old finished floors without removal. We recommend Acoustical Goo be used as the adhesive for the laminating with flexibility for movement of the structure below the ceramic floor assembly.

What is recommended thickness for ceramic tile wall backerboard?
We generally recommend 12mm (1/2") and 9mm (3/8"), but thinner magnesiacore can be used when laminating over existing walls.

What type of edge does Magnesiacore have?
Magnesiacore comes with a 90 degree square edge. The core is as dense as the surface and is not friable. There is also no paper face or skin to worry about. This allows magnesiacore to be machined with "v" grooves or T&G (tongue and groove) joints, which can glue together as butt joints instead of taping. For making tapered edges, a thickness of the face surface can be removed to create any bevel type, width, or amount of recess for taping or other treatments. Edges can also be sanded smooth and rendered the same as the surface of the board or planed ready for paint. This allows corners to be finished square without the use a cornerbead or "J" trim for exposed edges.

Do I need to pre-drill or countersink for screws?
Magnesiacore is more dense than drywall but less dense than cement board. Standard lightweight drywall screws will self-drill, but the wide head may break-off instead of countersinking if not pre-drilled. Standard weight carpentry screws with smaller heads are therefore recommended. Stainless Steel screws are recommended when necessary to avoid rust.

Will magnesiacore take screws and nails?
Yes. For fastening onto magnesiacore with screws, pre-drill a starter hole smaller than the shaft of the screw. This will create sharp threads and hold stronger than plywood. The same process of a starter hole can be used for nails. Without a starter hole, the threads tend to strip and give a weaker hold.

What paint surface preparations are suggested, if any?
Magnesiacore surface is suitable to receive painting and sealers without requiring special surface preparation. Different surface effects can be created by rubbing with steel wool to polish the surface to a shine; alternatively, light sandpaper will produce a uniform dull surface. To fully clean the surface and remove dusting, wipe with a damp cloth of water with 10% vinegar. This creates the highest possible bond for use with the most demanding coatings and adhesives.

Does Magnesiacore require special primers for painting?
Magnesiacore can be treated the same as plaster, cement or plywood. Primers are recommended when required by the coating as with any other porous material like cement, plaster and wood. Most paint products will generally adhere better on magnesiacore than they do on the materials they are traditionally used for.

What is required for magnesiacore as a natural finish?
Magnesiacore requires a weatherproofing sealer to close pores and prevent staining and absorption from the elements. If the textured side is desired the logo can be easily removed by rubbing off with steel wool or light sandpaper.

The smooth side tends to have a shine, what is this?
The shine is produced by smooth sides of boards rubbing together, polishing them to a gloss. For a uniformly gloss surface, you can use steel wool to polish the surface further to achieve a natural gloss. Alternatively, using different grades of sandpaper will dull the surface and give different natural sheen effects.

What certification is available for different parts of the world?
Magnesiacore has the necessary properties to pass local testing for the applications described. We currently have the testing and certifications necessary for general non-structural uses for inside and outside of buildings. Please contact us to discuss certification and testing that may be relevant to your local jurisdiction.