Types of Wood for Woodworking: A Guide to Furniture Woods

November 30th, 2010

Solid wood

That is, wood cut into boards from the trunk of the tree — makes up most of the wood in a piece of furniture. The type of wood you choose determines the beauty and strength of the piece. Many varieties of wood are available and each has its own properties. The following sections introduce you to the most common types of soft- and hardwoods.

Sampling some softwoods

Softwoods aren’t weaker than hardwoods. Softwoods come from coniferous trees such as cedar, fir and pine. They tend to be somewhat yellow or reddish in appearance. Because most coniferous trees grow fast and straight, softwoods are generally less expensive than hardwoods.

It’s also relatively easy to find sustainably grown softwoods (woods grown on tree farms to ensure a endless supply of wood); this means you’re not contributing to the deforestation of the world and will always have a supply of wood for your projects.

Following is a list of common softwood varieties and their characteristics.

Cedar

The most common type of cedar is the western red variety. Western red cedar, as its name implies, has a reddish color to it. This type of wood is relatively soft (1 on a scale of 1 to 4), has a straight grain, and has a slightly aromatic smell. Western Red cedar is mostly used for outdoor projects such as furniture, decks, and building exteriors because it can handle moist environments without rotting. Western red cedar is moderately priced and can be found at most home centers.

Fir

Often referred to as Douglas Fir, this wood is very soft, has a straight, pronounced grain, and has a reddish brown tint to it. Fir is most often used for building; however, it’s inexpensive and can be used for some furniture-making as well. It doesn’t have the most interesting grain pattern and doesn’t take stain very well, so it’s best to use it only when you intend to paint the finished product. Douglas fir is pretty hard, rating 4 on a scale of 1 to 4.

This wood is worth mentioning because it is very common at your local home center and it’s so inexpensive you’ll probably be tempted to make something with it.

Pine

Pine comes in several varieties, including Ponderosa, Sugar, White, and Yellow, and all of them make great furniture. In some areas of the country (especially southwest United States), pine is the wood to use. Pine is very easy to work with and, because most varieties are relatively soft, it lends itself to carving.

Pine generally takes stain very well (as long as you seal the wood first), although Ponderosa pine tends to ooze sap, so be careful when using this stuff. Pine is available from most home centers, but it’s often of a lesser grade than what you can find at a decent lumberyard.

Redwood

Like cedar, redwood is used mostly for outdoor projects because of its resistance to moisture. Redwood (California redwood) is fairly soft and has a straight grain. As its name suggests, it has a reddish tint to it. Redwood is easy to work with, is relatively soft (2 on a scale of 1 to 4), and is moderately priced. You can find redwood at your local home center.

Honing in on hardwoods

 Most woodworkers love to work with hardwoods. The variety of colors, textures, and grain patterns makes for some beautiful and interesting-looking furniture. The downside to hardwoods is their price. Some of the more exotic species can be too expensive to use for anything more than an accent.

Some hardwoods are becoming very hard to find and are being harvested without concern to their eventual extinction (Brazilian rosewood comes to mind). Not only is this hard on the environment, it drives the price of the wood so high that making furniture out of it is out of the question for most woodworkers. If you can, try to buy wood from a sustainable forest (commercial tree farms that ensure the supply of the wood). Check out the National Hardwood Lumber Association or SmartWood.com for ways to support sustainable forestry.

Following is a list of common hardwoods and their characteristics.

Ash

Ash is a white-to-pale-brown colored wood with a straight grain. It’s pretty easy to work with (hardness of 4 on a scale of 1 to 5) and takes stain quite nicely, but ash is getting harder and harder to find. You won’t find ash at your local home center — it’s only available from larger lumberyards. Ash is a good substitute for white oak.

Birch

Birch comes in two varieties: yellow and white. Yellow birch is a pale yellow-to-white wood with reddish-brown heartwood, whereas white birch has a whiter color that resembles maple. Both types of birch have a hardness of 4 on a scale of 1 to 5. Birch is readily available and less expensive than many other hardwoods. You can find birch at many home centers, although the selection is better at a lumberyard.

Birch is stable and easy to work with. However, it’s hard to stain because it can get blotchy, so you might prefer to paint anything that you make with birch.

Cherry

Cherry is a very popular and all-around great wood; easy to work with, stains and finishes well with just oil, and ages beautifully. Cherry’s heartwood has a reddish-brown color to it and the sapwood is almost white. Cherry has a hardness of 2 on a scale of 1 to 5. This is a very common wood for furniture-making and is available from sustainably-grown forests. You won’t find cherry at your local home center, so a trip to the lumberyard is necessary if you want to use it. Because it’s in demand, cherry is getting somewhat expensive compared to other domestic hardwoods, such as oak and maple.

Mahogany
One of the great furniture woods, mahogany (also called Honduran mahogany) has a reddish-brown-to-deep-red tint, a straight grain, medium texture, and a hardness of around 2 on a scale of 1 to 5. It takes stain very well and looks great with just a coat (or 10) of oil.

The only drawback is that mahogany isn’t being grown in sustainable forests (not a big deal unless you want to ensure that it’ll be around forever). Forget going to your home center to get some — the only place to find mahogany is a decent lumberyard (and it’ll cost you).

Maple

Maple comes in two varieties: hard and soft. Both varieties are harder than many other woods; hard maple is so hard (a 5 on a scale of 1 to 5) that it’s difficult to work with. Soft maple, on the other hand, is relatively easy to work with. Because of their fine, straight grain, both varieties are more stable than many other woods. They also tend to be less expensive than other hardwoods. You won’t find maple at your local home center, but most lumberyards have a good selection of it.

Oak

Oak is one of the most used woods for furniture. Available in two varieties — red and white — oak is strong (hardness of about 4 on a scale of 1 to 5) and easy to work with. White oak is preferred for furniture-making because it has a more attractive figure than red oak (white oak is also resistant to moisture and can be used on outdoor furniture).

This is one wood that can be found quarter-sawn (the most stable cutting option available). In fact, quarter-sawn white oak is less expensive than some other hardwoods like cherry, for instance. The grain has a beautiful “ray flake” pattern to it. Red oak can be found at most home centers, but if you want white oak, make a trip to the lumberyard.

Poplar

Poplar is one of the less expensive hardwoods. It’s also fairly soft (1 in hardness on a scale of 1 to 5), which makes it easy to work with. Poplar has a white color with some green or brown streaks in the heartwood. Because poplar is not the most beautiful wood, it’s rarely used in fine furniture and if it is, it’s almost always painted. Poplar can be a good choice for drawers (where it won’t be seen) because it is stable and inexpensive. You can find poplar at larger home centers, but a lumberyard will have a better selection.

Teak

Teak is becoming rarer as the days go on, but it is the staple for fine outdoor furniture. Teak is highly weather-resistant and beautiful (not to mention expensive — can you believe almost $24 a board foot?). Teak has an oily feel and a golden-brown color. It rates a 3 on a scale of 1 to 5 for hardness and is only available from larger lumberyards and specialty suppliers.

 

Walnut

With a hardness of about 4 on a 1 to 5 scale, walnut is a rich brown wood that’s easy to work with. Unfortunately, walnut is somewhat expensive (usually around $8 a board foot) and finding large boards for big projects is getting difficult. In spite of this, walnut is still a great wood to work with and lends itself nicely for use as accents and inlays to dress up a project. You won’t find walnut at your local home center and you may need to special order it from a lumberyard if you want a large quantity.

 
 
A Guide to Furniture Woods

Almost any type of wood could be used to build furniture, but some woods have always been favored for their beauty, durability, and workability. Before 1900, most furniture was made with these woods: walnut, oak, mahogany, rosewood, fruitwoods, and rare wood veneers and inlays were in common use. American Colonial furniture, dependent on local availability, was made with maple, oak, walnut, birch, and cherry, as well as pine. The preferred furniture woods were readily available, so less attractive or durable woods were used only for hidden parts inside a piece. For this reason, pre-1900 furniture is almost always worth restoring.

As these preferred woods have become scarcer and more expensive, furniture has been made with more abundant woods; the traditional favorites have become rare. Today, most furniture is made with ash, pine, gum, and poplar; pine, fir, and other inexpensive woods are used for hidden parts. The rare woods are used only for very good furniture, and they’re often used in combination with the less expensive woods.

Being able to identify the type of wood used for your furniture can help you determine its real value. Wood identification can sometimes be the deciding factor when you aren’t sure if a piece is worth refinishing or if it should be thrown away. There’s a good chance that a beat-up old dresser, for instance, was built with what today is considered a rare wood. In this article, we’ll show you how to examine a piece of furniture and what details or identifying marks to look for to easily identify the type of wood used to create it. It will be helpful to know the basic characteristics in all woods, such as hardness, grains, and color.

Wood Characteristics

Hardness

The simplest way to describe a wood is to say it’s a hardwood or a softwood, but this description can be deceptive: not all hardwoods are hard, and not all softwoods are soft. The hard/soft classification is a botanical one — hardwoods are flowering trees; softwoods are conifers. Although most hardwoods are harder than most softwoods, there are exceptions.
In general, hardwoods are more valuable than softwoods, because the wood is scarcer. But this isn’t always the case — gum, for instance, is a hardwood that competes in price with softwoods. A more practical way to identify wood is by its grain and color.

Wood grain and color

The cell structure of a tree, different for each species, determines its grain. Hardwoods have tubular cells called vessels, visible as pores in the wood. If the cells are large, the texture of the wood is slightly rough, or open; a filler may be needed to smooth the surface. If the cells are small, the texture is smooth; these woods, described as close-grained, don’t require filling. Oak, walnut, ash, mahogany, rosewood, and teak are all open-grained woods; beech, birch, maple, cherry, satinwood, gum, and poplar are close-grained. Softwoods don’t have vessel cells, but for all practical purposes can be considered close-grained.

All trees have annual growth rings, made up of the cells formed during each year’s growing season. The types and arrangement of the cells determine how the wood looks. There are woods with subdued and with clearly defined grains; there are straight grains, stripes, swirls, waves or curls, ripples, eyes, and mottled effects. There are colors from white and pale yellow through red, purple, and black. Every species has its own particular grain and color, and although they vary from tree to tree, these characteristics can almost always be used to identify the wood.

Furniture woods are chosen and valued for the character of their grain and color. Hardwoods usually have a richer and finer-textured grain than softwoods, but there are rich grains of all colors and patterns. Woods with very distinctive patterns are usually more valuable than woods with subdued or indistinct patterns, and the weaker-grained woods are often stained to give them character. This is why the old finish must be completely removed before you can tell for sure what wood a piece of furniture is made of.

How to Assess Wood

How do you begin to identify the type of wood used for your furniture? This may seem difficult at first, but you’ll find it easier as you gain experience. With practice, you may be able to recognize various woods by smell and touch as well as by color and grain. You should ask yourself some key questions:

Consider the piece of furniture itself.

About how old is it, and what style is it? Some types of furniture are made with specific woods — ash, for instance, is widely used in bentwoods — and most new furniture is made with woods not used for older furniture.

Look at the color

Although color can vary considerably from tree to tree, its tone is fairly constant within a species; the color intensity may change, but not the quality. Some woods have very distinctive color characteristics — poplar, for instance, is the only wood with a green tinge to it, and rosewood can be dark purple.

Finally, look at the grain.

Is the wood open- or close-grained? Are the pores evenly distributed, or are they concentrated at the growth rings? Is the grain straight or wavy, mottled or swirled?

Now that you have closely looked at your furniture, you might notice it is made with veneer (thin layers of wood) or a combination of woods. Both are common practices for furniture building.

Veneers and Inlays

Because rare woods are scarce, and because they’ve always been more expensive than other woods, many types of furniture, both new and old, are made with veneer, a thin layer of wood glued to a base of less expensive wood or plywood. In old furniture, veneers and inlays of rare woods were often used to form designs or special effects; highly figured burl woods and other exotic woods were especially prized. In modern furniture, veneers are used primarily where solid wood is unavailable or too expensive.

Many different woods are used for veneers and inlays. Some veneers are cut from the crotch or butt of a tree, where the grain is more interesting; some are cut at an angle to produce a particular pattern. Some highly prized grain patterns, such as the bird’s-eye figure in maple and the burl patterns, result from irregular growth. Some veneer woods, such as the burl woods, are not usable for solid construction because the wood isn’t strong enough. Ebony, in contrast, is veneered because it’s much too heavy to be used alone.

Veneers are fragile, and they can be damaged by refinishing techniques. Veneers are common in modern furniture construction, so take a good look at your furniture before you start to work on it. Any highly figured wood is probably a veneer.

It isn’t always obvious what’s veneered and what’s not. Sometimes the veneer is visible at the edge of the wood surface, a thin layer glued over the base wood. If you can’t see a joint at the edge, look at an unfinished area under the piece of furniture. If the unfinished wood looks the same as the finished surface, the piece of furniture is probably solid wood. If there’s a considerable difference, it’s probably veneered.

Wood combinations

Another consideration is that many types of modern furniture are made with two or more kinds of wood, to keep the cost down. Rare woods are used where appearance is important, such as table-tops; the more common woods are used for less conspicuous structural pieces, such as table and chair legs. This multiple-wood construction isn’t always easy to see until the old finish is removed — a table you think is walnut, for example, may turn out to have gum legs, stained to match.

Furniture made with more than one wood eventually needs special refinishing treatment. If you find yourself with a multiple-wood piece, you may have to stain and finish the common wood again to match the wood of the most conspicuous surface.

Once you are familiar with the color, grain, and construction style of your furniture, you can use that information to determine the specific kind of wood or woods used. Check out the next section for tips on how to easily identify common furniture woods.

For more information, please visit our website:

http://www.dutchtouchwoodworking.com/

Woodworking Finishing & Coping Saw Tips

November 30th, 2010

Do You Want a Simple Process?

Numerous “experts” state their method of woodworking finishing. Most of them recommend a different method — using different abrasives to a wipe-on top coat. Which one is right for you?

Try This Simple Method of Woodworking Finishing:

1. Use 120 grit sandpaper for final sanding. This allows the stain to penetrate the wood. Use 220-grit sandpaper on the edges. This tends to make the end-grain take the same color as the face-grain.

2. I like using an orbital sander for final sanding. It doesn’t leave gouges and scratches like other sanders. After trying different types of sanders, I settled on the Makita B06030. It gives consistent results and is variable speed. Hook & loop sandpaper is easy to change. See the Orbital Sander Page for more detail.

3. Hand-sand the edges with 220-grit using a sanding block or your hands depending on contour. See the Sandpaper Tips Page for more details on a quality sanding block for woodworking finishing.

4. Use a scraper in tight places where there are glue spots. It is easier to use than sandpaper. Once you have experience, the scraper gives you a nice surface.

Important Woodworking Finishing Tip:

Clean the air.

Allow a day for the dust to settle after sanding. If you have an air cleaner, use it during sanding and during your finish coats.

Remove the dust from your project prior to staining. You can vacuum it or you can use a tack cloth. I prefer using the Tack Cloth, since it removes all of the dust.

Woodworking finishing requires that you use a high quality stain. I like MinWax penetrating stain. You can mix stain to get your desired color. Example: A mix of Golden Oak (which is a little darker than I like) and Ipswich Pine (which is a little lighter and has some bright color) gives my color of choice.

You want to protect your hands from clean-up later. Get some quality throw-away gloves.

Use a quality brush or rag to apply the stain. I tried an expensive paintbrush to cheap foam brushes. The best ones are high-quality foam brushes.

Cover the floor and work area with some plastic. Apply the stain with a quality foam brush.
Let the stain penetrate for around 30-45 minutes. Then wipe off with a lint-free cloth. This gives a uniform color to the wood. Sometimes you can wait longer; it depends on the project. Allow the stain to dry for a day, and then apply another coat. Rub the second coat off around 20-30 minutes or so. The second coat gives the project a richer finish than one coat. Let it dry for another day. After it is dry, you may apply a third coat. It just depends on the color you want to achieve.

Now let the stain dry for several days. It should be thoroughly dry prior to the finish coats. It is better to wait a little longer than apply the finish coat too soon.

Take the tack cloth and remove any dust that may have settled. If the project is not too big, you could enclose it in a box. Then seal all edges of the box. That will keep most of the dust off.

I like using MinWax Fast Drying Polyurethane. It gives an excellent finish and dries in about four hours, depending on humidity. I do NOT like water-based finishes for my projects. Once again, use a quality foam brush. There are extra tips on the Foam Brush Page, such as how to store for multiple uses.

Brush in one direction and make sure that you keep the surface “wet”. If the project is not too large, make very light strokes down the entire length. Just make sure the polyurethane is not drying. Two coats are normally sufficient. For rougher use, such as table tops or drawer fronts, try using three coats. Use 220-grit sandpaper on a block to lightly sand between each coat.

Just remove any bumps on the surface. Of course, after the light sanding, you clean up with a tack cloth.

Once you have the desired finish, wait three days prior to final finish. This extra step makes your project take on a professional look. This is needed for quality woodworking finishing.

I do not like steel wool, since it leaves a residue on the surface. Some of the other recommendations use different types of pads, but they are not foolproof either.

Squirt some Formby’s Lemon Oil Treatment on the poly-surface. Using 600-grit wet/dry sandpaper and a block, gently smooth out the finish. If the sandpaper gets “dry”, squirt on some more Lemon Oil Treatment. You can squirt the Lemon Oil Treatment directly to the sandpaper.

This is especially good in hard to reach places. This final treatment removes any blemishes. It gives a professional touch to your project without a lot of work. You will be amazed at the results.

What is the advantage of using the coping saw to a miter saw?

 The coping saw won’t cut your fingers off on the first pass!

Anytime I’m cutting funny angles, I always ask myself what’s going to get the job completed as fast, accurate and safe as possible! The miter saw is always going to give you the truest and fastest cut. In a perfect world! However, we live in a world of out of plumb walls and doors, crazy ceiling angles. All kinds of fun stuff to turn a ten minute project into a two hour headache. Or maybe longer if you’re not sure what you’re doing. That’s why the coping saw is such an invaluable tool to anyone considering installing moldings in there home.

The primary purpose of a coping saw is to cope the profile of an inside miter after the piece has already been cut with a miter saw. (whether hand miter saw or electric miter saw).

The advantage of using a coping saw over a miter saw when you have to make crazy little cuts. Is having the flexibility to cut the smaller and odd shaped cuts and notches that are either too dangerous or just impossible to make with the miter saw. You always want to be thinking about your fingers!

On all your outside angles, the electric miter saw is the way to go! This is going to give you the easiest and most accurate outcome. I’d definitely recommend cutting your crown a little longer and work your way down to the exact cut. This gives you the flexibility if you have to change the angle a little in order to make a tight fit.

 

Coping Crown Molding With A Coping Saw

So you want to install crown molding the easy way?

The first step would be to learn how to properly use a coping saw!

The first question I would ask anybody applying for a job is whether or not they could use a coping saw. Only the dummies would lie about it and get run off!

The coping saw is a small hand saw used by professional finish carpenters for making fine deep cuts when fitting moldings. The object is to cut the backside of the profile so two pieces will fit on an inside corner perfectly! No Caulk or glue. Once the proper technique is mastered, coping moldings and other various woodworking cuts will be a cinch. You’ll save time, material and a whole lot of aggravation dealing with out of square corners that are almost guaranteed to be in every house.

A coping saw can be purchased with a pack of blades at most local home improvement centers for about the same price as a twelve pack of Guinness. I just wouldn’t recommend drinking the Guinness until after the job is done. Or you’ll probably need more than caulk!

When coping a piece of crown, you’re actually hand cutting the profile of the molding so it fits into an identical piece. This does take a little practice so be patient, get some scraps and go to work, You won’t regret it.

The first step is to get the blade pointed in the right direction. I’ve witnessed two different methods of coping over the years, (the push to cut or the pull to cut). I’m a push man myself!

Here’s why!

The object of using any tool is to let the tool do the work. By standing above the work piece and using gravity to help push the blade through the wood to make the cut instead of pulling, you end up with a much easier and more controllable cut.(Let the blade do the cutting)
Pushing the blade into the cut also directs the burrs towards the inside of the piece and not to the finished outside. This will eliminate any need for sanding and leave a much finer cope.
When coping crown you don’t have to cope it in all one pass either, the object is to get the cope as accurate as possible and rushing will only lead to a lousy joint that needs filling. I’ve found that it’s easier to cut the piece out in sections and work towards intersecting points, rather then trying to round corners and bend the blade all to hell.
Undercutting is also key to getting tight coped joints. The more you undercut, the more forgiving out of square walls and wavy ceilings will be. Another trick to getting tight crown joints is to not nail the molding in the corners until both pieces are fitted. This will give a little play in the corner for twisting the crown molding into place.

For more information, please visit our website:

www.dutchtouchwoodworking.com

Woodworking Service 101

November 30th, 2010

Removing the Paint From Furniture

When the paint remover has done its job and the surface is softened, you are ready to remove the loose paint. It is usually best to remove as much remover and paint as possible the first time. A scraper works well for this.

Paint or varnish can be sanded away with any type of power or hand sander. For bigger sanding jobs, you’ll want to use a power sander. Belt, disk or drum sanders can be used.

Although sanding removes a painted surface quickly and easily, it has one basic disadvantage – it also removes some of the wood surface underneath the paint. If you are working on a fine piece of furniture, sanding is not recommended. When sanding old paint or varnish from the surface, use open coat, coarse sandpaper. Fine sandpaper clogs up quickly, making it ineffective as a paint remover.

After cleaning and allowing to dry, most surfaces will need to be lightly sanded to prepare the surface. With a better grade of remover, no sanding or swabbing is necessary. Some types of paint can be especially hard to remove. This usually requires a second coat of paint remover after you have removed the first coat of enamel. If the surface has several layers of paint, it may be necessary to apply paint remover a third time. As a rule, sanding is recommended only on extremely rough jobs. Chemical paint removers are much more effective and easier to use.

Drywall Tips:

Very few people have ever heard of “hydrous calcium sulphate.” And even fewer are aware that hydrous calcium sulphate – CaSO4.2H2O as chemists know it – is gypsum, the rock that nobody knows.

In addition to being found in the Egyptian pyramids, gypsum rock is referred to in the ancient cuneiform scripts of the Assyrians. Its use was probably developed by the Greeks, whose influence certainly remains in the name by which the rock is known. They called it Gypsos, the source of our word “gypsum.”

Gypsum is a rock that, like limestone, occurs naturally in many parts of the world, and like limestone, in an absolutely pure form it is white. However, the usual presence of darker impurities produces rock in varying shades of gray, brown, and even black. Since it normally is found close to the surface, gypsum can be mined or quarried easily.

The biggest part of the gypsum rock used in this country goes into wallboard for homes. Gypsum “boards” are formed by sandwiching a core of wet plaster between two sheets of heavy paper. When the core sets and is dried, the sandwich becomes a strong, rigid, fire-resistant building material. Fire-resistant because in its natural state, gypsum contains water, and when exposed to heat or flame, this water is released as steam, retarding heat transfer. Manufactured in unbelievable quantities on continuous machines almost a quarter mile in length, gypsum wallboard and lath, prefinished wallboard, and gypsum sheathing for use under exterior finishes are among the most important materials used in housing.

Here are a few other ways in which gypsum is seen during an average day.

First of all, there is toothpaste. Gypsum forms the basis for some of the well-known brands of toothpaste, and thereby helps to pay the salary of some of television’s best-known entertainers.

Most of the fixtures in bathrooms are made of clay formed in a mold of gypsum plaster, and chances are that gypsum board is behind the wall tile.

At the breakfast table, plates, cups, and saucers are present which were shaped on or in a gypsum plaster mold, a mixture of plaster of paris and water. So were the sterling silver handles of knives, forks, and spoons.

On the way to work or school, people step on sidewalks made of Portland cement, which contains a percentage of gypsum to regulate the setting time.

Maybe their walk is covered with chalk marks from the game the children played the night before. But of course, they weren’t made by chalk at all, but by a molded stick of, you guessed it, soft gypsum plaster. Many streets and highways also contain their share of gypsum.

Doctors and dentists, too, use gypsum for everything from dental molds to splints.

Benjamin Franklin, the great experimenter, was one of the first to introduce it in this country when he used ground raw gypsum, called land plaster, on his farm.

Today, thousands of tons of land plaster are used in the U.S. each year.

DRYWALL FAQs:

What is the “R” Value for gypsum board?

For purposes of calculating “U” values, the “C” factor for 1″ gypsum board is 1.2; Resistance “R” for 3/8″ board is 0.32; for 1/2″ board 0.45; for 5/8″ board 0.56; and for 1″ board 0.83.

What’s the difference between “regular” and “type X” gypsum wallboard?

ASTM C 36 designates two types of gypsum wallboard, regular and type X. Type X wallboard, which is typically required to achieve fire resistance ratings, is formulated by adding noncombustible fibers to the gypsum. These fibers help maintain the integrity of the core as shrinkage occurs providing greater resistance to heat transfer during fire exposure.

By ASTM definition, type X gypsum wallboard must provide: not less than a one hour fire resistance rating for 5/8″ board or a 3/4 hour fire resistance rating for 1/2″ board applied in a single layer, nailed on each face of load-bearing wood framing members, when tested in accordance with the requirements of ASTM E 119, Methods of Fire Test of Building Constructions and materials.

Additionally, the Gypsum Association requires 1/2″ type X gypsum board to achieve a one hour fire resistance rating when applied to a floor ceiling system, as described by GA File Number FC 5410, in GA 600, the Gypsum Association Fire Resistance Design Manual.

What is Hi-Impact Wallboard?

 
Hi-Impact wallboard is a specially designed product consisting of 5/8″ Fire-Shield Type X wallboard with a stronger core and face paper that is backed with Lexan polycarbonate film manufactured by GE Plastics.

What is “Green board”?

Green board is designed as an indoor tile backer board and can be used as sheathing. Gypsum sheathing has a moisture-resistant paper and a treated or non-treated gypsum core. Green board also has a moisture resistant paper and a treated core. Green board has a tapered edge while sheathing is a square edge product. If you plan to attach vinyl or steel siding over the sheathing, there will be a dip at the taper; therefore, this application is unadvisable.

If the substrate is a stone or brick cavity wall, however, the application can work.
We strongly suggest using building felt over this type of sheathing. It appears that for any high humidity application Green Board he preferred product. But that’s not necessarily the case.

For ceiling applications, green board requires extra support. According to Gypsum Association guidelines, green board in a ceiling application needs 12″o.c. support. f supports are 16″ o.c., 5/8″ green board should be used. Why is this additional support needed? Moisture repellents, such as the asphalt and wax emulsions in the green board core formulation, act as lubricants. These lubricants cause the gypsum crystals to slip easily, resulting in board sag.

For bathroom ceiling applications, we recommend regular or Type X board. Simply apply a good quality sealer and two coats of latex based paint after installation.
As your house gradually settles over time, small changes in the alignment of door jambs can cause doors to stick. Other things, such as loose hinges or new thick carpet can make it difficult to open or close a door. Fixing each of the things that causes a door to stick is easy, though and requires at most a hand plane or circular saw.

When a door sticks in the jamb (the fixed frame around the door) look to see where the door hits the jamb. If it hits on the top of the door on the lock side of the door, shim the top hinge with cardboard to move the lock side of the door down a hair, away from the jamb. Remove the screws from one side of the hinge as in photo 1, cut a piece of thick cardboard (not corrugated) to the size of the mortise for the hinge and reinstall the screws.