Gypsum

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What is Gypsum (The Magic Mineral)?
Gypsum is a non-metallic mineral, found as a rock composed of 79.1% calcium sulphate and 20.9% water by weight. Gypsum was formed during the Silurian period of the Paleozoic Era of the Geological calendar. This corresponds to about 300 million years ago. In absolutely pure form, gypsum rock is white. However, it contains impurities whose presence makes the rock appear gray, brown, pink or almost black.

Gypsum and its products have been known and used from earliest times. The Ancient Assyrians called it Alabaster and used it for sculpturing. Five thousand years ago the Egyptians had learned to make plaster from it. The ancient Greeks named this mineral "Gypsos", from which we have taken the name "Gypsum". Another form of gypsum rock, clear and transparent in layers like mica, was used as temple windows many centuries before glass was invented. The Greeks named it "Selene" after their Moon Goddess; today we call it Selenite.

Today gypsum is used in the manufacture of many products including, but not restricted to, drywall board, plaster, sheathing, toothpaste, blackboard chalk, the filler in paints. It is also used for surgical casts and moulds for false teeth.

Does drywall go up horizontally or vertically?
You can put the board up either way. What generally dictates the way the drywall goes up is the way that minimizes the amount of joints you will have to tape. Walls eight feet and under go up horizontally. Walls over eight feet usually go up vertically.

What size are the sheets?
The drywall sheets are available in many sizes. Normal stocked lengths are 4 foot wide by 8, 10, or 12 foot long.

What types of drywall are available?
There are many types of drywall. Regular drywall is used for most wall and ceiling applications. Specialty drywalls are engineered for specific needs. For instance FIRECODE drywall is used in areas that need specific fire and safety requirements. Water resistant drywall is used in areas that may come in contact with water such as bathrooms. There are also Sag-Resistant drywalls engineered with enhanced cores to resist sagging in critical ceiling applications.

How do you cut drywall?
Drywall is very easy to cut. All you need to do is score the face paper with a utility knife using a straight edge and break the board away from the cut. Once the board is broken you then score the back paper with a utility knife.

How do you fasten drywall?
On wood stud framing you may use drywall nails or drywall screws. On steel stud framing you must use drywall screws.

How do you cut DUROCK®?
DUROCK® is very easy to cut. All you need to do is score the face of DUROCK® with a utility knife and a straight edge until you cut through fibreglass that lies just beneath the surface of the cement board. This may take 2 passes. Once you have cut through the fibreglass you break the cement board away from the cut and then score the back of the cement board to cut through the fibreglass that lies just beneath the back surface.

What side of DUROCK® do you use?
DUROCK® is designed to be used on either side.

What type of fastener do you use?

To fasten DUROCK® to wood framing you may use hot dipped galvanized roofing nails or cement board screws. To fasten DUROCK® to steel studs you must use cement board screws. NEVER USE DRYWALL SCREWS.

How do you tape the joints of DUROCK®?

To tape the joints of DUROCK® you first prefill the joint with what ever you are using to set your tile. That would be either portland cement or mastic. While the taping material is still wet you immediately embed a polymer coated fibreglass tape designed specifically for cement boards into the taping material. Never use fibreglass or paper drywall tape.

What happens to DUROCK® if it gets wet?

Nothing will happen to DUROCK® if it gets wet. It is designed to get withstand extreme moisture.

How do you cut FIBEROCK®?
FIBEROCK® is very easy to cut. All you need to do is score the face of the panel with a utility knife and a straight edge. This may require 2 passes. Once the panel has been scored you break the panel away from the cut. Uneven edges may be rasped clean if required.

Is FIBEROCK® environmentally friendly?
Yes, FIBEROCK® is certified to be 95% recycled.

What types are FIBEROCK® are available?
FIBEROCK® is a specialty panel and is available as an interior abuse resistant wall panel, a tile backer, and a residential floor underlayment.

How do you tape the joints of FIBEROCK®?
For interior FIBEROCK® you pre-fill the joint with DURABOND® Joint Compound and embed paper drywall tape immediately into the DURABOND® while the DURABOND® is still wet. Do not use fibreglass tape. Once the DURABOND® has set you apply a second and third coat of regular weight joint compound making sure each coat is completely dry before the next coat is applied.

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