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A couple of things to think about before...

repairfinder — Fri, 03 Oct 2008 21:01:46 +0200

If you are thinking about remodeling your home or office, there are many things to consider. One of the biggest is “should I do it myself?” There is no easy answer to this question, but you can help yourself decide by considering the following questions:

1. Do I have the time?

Remodeling can take a considerable amount of time, even for the experts. Most of the time remodeling is actually more difficult than new construction. One of the reasons for this is that you have to prepare the existing components of your structure to blend in with the new.

2. Do I have the know-how?

Your remodeling project will likely require some specific skills to ensure a successful result. These can include carpentry, painting, drywall finishing, flooring, plumbing, electrical, concrete work, excavation, etc. You’ll want to carefully assess your abilities in the skills you’ll need for your own project.

3. Do I have the tools and equipment needed?

Since so many skills are involved, most property owners do not have the needed tools and equipment. If you can get the tools by purchasing, renting or borrowing them, do you have the skills to use them effectively and safely?

4. Do I have enough help?

Remodeling can be very labor intensive; two hands are often not enough. You can always use someone to help carry materials or equipment, or you might need skilled help in order to complete the job in a reasonable time. If you need help, will you have access to the kind of help you need, when you need it?

5. Am I physically able to do the work?

Remodeling is usually strenuous work, involving climbing ladders, working on scaffolds or heavy lifting. You’ll need to decide if you’re physically able to do that kind of work for the extended period your project may take.

6. Do I have a clear idea of what I am trying to accomplish?

Can you draw the necessary building plans, or will you need to get someone else to do this for you? You may need to hire an architect if your remodel is very complex. An architect can help with traffic flow and other factors that may arise when you change rooms, or move walls and doorways.

7. What is my budget?

You should make a careful estimate of all the costs of your project before any work is started. Calculate the costs of all materials, equipment rental, tools, labor, subcontractors etc. Don’t forget to add a budget for any unknowns or surprises that may be revealed later!

8. What kind of subcontractors am I going to need?

You will probably need some skilled subcontractors to perform specialized work that you can’t do. Do you have the time to deal with those subcontractors personally, and do you have the knowledge needed to negotiate with them? If you are unprepared in this area, it can cost you a lot later on.

You may decide when you’ve finished answering these tough questions that you’ll need some help. If you decide to hire a professional remodeling contractor, you should expect someone with years of experience in construction who can provide all the services listed above, including management of all the necessary subcontractors. Your contractor should take care of everything, and manage your project until it is completed in a timely and efficient manner.

Here’s how to find a good remodeling contractor:

1. Go to Repairfinders.com

On Repairfinders.com you will find only the best qualified professionals in your area. All it takes is a couple minutes of your time to find the right one that is best for you.

2. Check out references

Get previous customers’ opinion of the contractor and the work that was done. Talk to local vendors and suppliers to see if that contractor pays his or her bills.

3. Is the contractor local?

Does he or she have a local office, address or phone number? It’s easier to keep track of a local contractor; avoid hiring from out of town or state unless you thoroughly check them out.

4. Look at the contractor’s work

Make sure you look at previous projects or photos of completed work.

If you’re looking for someone who has roots locally and is likely to be around to stand behind the work done on your project, you might also find out if the contractor you’re considering is involved in the community or in non-profit organizations, or provides support for community projects.

Water’s natural beauty preptuated throug...

repairfinder — Wed, 01 Oct 2008 20:43:32 +0200

A traditional fountain is an arrangement where water issues from a source, fills a basin of some kind, and is drained away. Fountains may be wall fountains or freestanding. In fountains, sheets of water may flow over varied surfaces of stone, concrete or metal. Basins may overflow from one into another, or the overflow may imitate a natural cascade. Many fountains are located in small, artificial, ornamental ponds, basins and formal garden pools, and often they include sculpture.

One of the most common features of a fountain, if there is enough pressure, is one or more jets, in which water is forced into the air under pressure to some height. A famous example of such a modern fountain rises from the surface of Lake Geneva.

Early fountains depended on the natural gravitational flow of water, from a spring or aqueduct supplied by a distant and higher source of water, which provided hydraulic head.

Hellenistic hydraulic engineers employed great originality in designing fountains, where the water pressure might be employed to animate automata and water organs.

Iraqi engineer and inventor al-Jazari first described reciprocating motion in 1206 when the kings of the Artuqid dynasty in Turkey commissioned him to manufacture a machine to raise water for their palaces. The finest result was a machine called the double-acting reciprocating piston pump, which translated rotary motion to reciprocating motion via the crankshaft-connecting rod mechanism.

Other early fountains were geometrically regularized springs, developed in the classic Persian garden. These gardens were typically enclosed and were designed to provide relaxation. The effect of sunlight was the main concern regarding the structural aspect of the Persian garden design. Shapes and textures were specifically chosen for their ability to direct sunlight. In the 16th century, elaborate fountain displays were garden features of Mannerist gardens of Central Italy and the Mughal gardens of India.

Early Modern English employed fountain to refer to a natural spring water or source, which the 16th century garden fountain might consciously imitate in a grotto.

Christian allegory made much use of the concept of the fountain, specifically the Fountain of Life, associated with the rebirth that was intended to be experienced at the Baptismal font. The Fountain of Life appears in Christian illuminated manuscripts of Late Antiquity, and elaborate Gothic fountains formed centerpieces for enclosed gardens. An offshoot of the Fountain of Life was the legend of the Fountain of Youth, which Juan Ponce de León sought in Florida. From the Fountain of Youth one can drink to gain immortality, or to regain one’s youth.

The practical Romans marked the delivery end of aqueducts with a public fountain, a practice that was revived in Rome in the 15th century, when the restored Aqua Felice once more delivered a symbolic presentation of its waters to Rome in the original Trevi Fountain, since replaced by the familiar Baroque fusion of water, architecture and sculpture.

Animated fountains often use laminar jets that provide water that moves like ping pong balls in animation, so that it breaks up, as the height varies, and the behavior of each jet operates independently with up to 5 Hz modulation frequency (1/5 second), so that the water packets collide with themselves. For example, such fountains can spit up one ball of water, which then explodes, showering people with a fine mist.

A musical fountain is a type of fountain that dances in time with recorded or live music, controlled either by a computer or by a live “organist” operating the fountain through a switchboard. Notable examples of this are fountains on Vasilievsky Island in St. Petersburg, Russia, and the fountains of the Bellagio in the Las Vegas Strip.

A splash fountain or bathing fountain is a fountain intended for people to cool off in. Although many fountains were not designed as bathing fountains, children of all ages often use them for that purpose. Some fountains are fenced in, or have raised edges as a barricade to keep people out. In other situations, fountains are designed to allow easy access, and feature nonslip surfaces, so that people can safely use them to cool off in on hot summer days.

Splash fountains have zero standing water, to eliminate possible drowning hazards, so that no lifeguards or supervision is required. These splash pads are often located in public pools, public parks, or public playgrounds (known as “spray grounds”).

A recent example of a public splash fountain, intended for water play, is the one located in Toronto’s Dundas Square. It consists of 600 ground nozzles arranged in groups of 30 (3 rows of 10 nozzles). Each group of 30 nozzles is located beneath a stainless steel grille. Twenty such grilles are arranged in 2 rows of 10, right in the middle of the main walkway through Dundas Square. Both the architects and the designers have confirmed that these were intended for water play, and the facility operators have confirmed that the water is treated to pool water quality standards, and that the health department tests the water quality, at least once a day. The entire surface of Dundas Square is made of special nonslip square granite slabs that match the size of the metal grilles. The special texture on the slabs ensures that they are not slippery when wet.

Spray fountains are designed to serve as a play area where children (and sometimes adults) can run around and cool off under a canopy of water. Spray fountains are becoming popular in areas where the construction of public pools is difficult or costly, such as urban areas. However, spray fountains can also be used to enhance a pool’s surrounding play area.

A water fountain or drinking fountain is designed to provide drinking water and has a basin arrangement with either continuously running water or a tap. Modern indoor drinking fountains may incorporate filters to remove impurities from the water and chillers to reduce its temperature. In some regional dialects, water fountains are referred to as bubblers. Water fountains are usually found in public places, like schools, rest areas and grocery stores. Many jurisdictions require water fountains to be wheelchair accessible (by sticking out horizontally from the wall), and to include an additional unit of a lower height for children and short adults. The design that this replaced often had one spout atop a refrigeration unit.

In modern fountains, the traditional gravitational pressure from an unseen reservoir at a higher level is not always practical. In many circumstances fountains obtain their water from a closed, recirculating system that must still be filled at the start from the local water supply system and also topped up through its life to offset the effects of evaporation. Allowance must also be made to handle overflow in the case of heavy rain.

The pressure that causes water to move through the fountain may be produced instead by a motor-driven (often-submersible electric) pump. “Static head” is useful to quantify this pressure.

A water filter, typically a media filter, removes particles from the water — this filter requires its own pump to force water through it and plumbing to remove the water from the pool to the filter and then back to the pool. The water may need chlorination or anti-algal treatment, or may use biological methods to filter and clean water.

The pumps, filter, electrical switch box and plumbing controls are often housed in a “plant room”. Low-voltage lighting, typically 12-volt direct current, is used to minimize electrical hazards. Lighting is often submerged and must be suitably designed. Floating fountains are also popular for ponds and lakes they consist of a float pump nozzle and water chamber.

Many civic fountains in public parks are commissioned in commemoration of either national or public figures.

There are also some limited fountain day celebrations. The University at Albany hosts an annual “Fountain Day,” a day on which the university community comes together to celebrate the arrival of spring and the near-end of the semester. Drawing large crowds, the fountain-centered event creates something akin to an urban beach.

A hydraulophone is a fountain that can be played as a musical instrument. These fountains are like woodwind instruments, but using water instead of air. The embouchure of the instrument occurs at the finger holes (referred to as “mouths”). Hydraulophones often have multiple “mouths”, so that a player can put each finger into a different mouth at the same time, in order to play chords, while independently manipulating each finger for separate and individual control of the embouchure of each note in a chord. A skilled hydraulist can slightly “bend” each note in order to play just intonation in any desired key, or to gently and fluidly vary intonation or temperament as a piece of music changes from one key to another.

There is a need for good water quality in contemporary fountains, regardless of their avowed intended use. Regardless of the fact that some fountains are designed and built not as bathing fountains, but are rather used simply as architectural decor, people will often drink from, bathe or wash their hands in any fountain. Additionally, fountain spray can contain legionella bacteria and has been linked to Legionnaires ‘disease outbreaks. Therefore, minimum water quality standards are necessary, regardless of intended use. Guidelines have been developed for control of legionella in ornamental fountains.

In theory, a freestanding water feature should not have a bather load, and consequently, many builders would not choose to install filters or sanitation devices. In reality, however, people will interact with ornamental water fountains in the most surprising ways. In Disneyland, for example, people have been reported to change their babies’ diapers and then wash their hands in the water fountain (thus adding unexpected bacteria and organics into the water).

In July 1997, an outbreak of cryptosporidiosis was connected to an ornamental fountain at the Minnesota Zoo, which did not have proper filtration and water treatment. Children played in fountains and swallowed water, and spurted the water out of their mouths to mimic the way nozzles in the fountain spurted the water. It was therefore necessary to put a fence around the fountain to keep people away.

In the United States fountain operators and owners are legally liable for failure to either fence-in fountains, or to properly filter, chlorinate or otherwise treat the water, if the fountains are not fenced in. If the water is unsafe, fences must be designed to keep people far enough away, so that they cannot touch the water, otherwise children get water on their hands, put their fingers into their mouths, and end up getting sick, thus subjecting owners and operators to legal liability.

If you are interested in adding a fountain to your home or office, Repairfinders.com is the perfect place for you. With many qualified professionals in your area, it will only take a couple of minutes to find the right person for you. Not only will a fountain bring you peace and entertainment it will also bring elegance to your home office.

Masonry… not just sticks and stones.

repairfinder — Wed, 01 Oct 2008 02:03:57 +0200

Masonry is the building of structures from individual units laid in and bound together by mortar. The common materials of masonry construction are brick, stone such as marble, granite, travertine, limestone; concrete block, glass block, and tile. Masonry is generally a highly durable form of construction. However, the materials used, the quality of mortar and workmanship, and the pattern the units are laid in can strongly affect the durability of the overall masonry construction.

Applications

Masonry is commonly used for the walls of buildings, retaining walls and monuments. Brick is the most common type of masonry and may be either weight bearing or a veneer. Concrete block masonry is rapidly gaining in popularity as a comparable material. Blocks - most of which have hollow cores - offer various possibilities in masonry construction, generally providing great compressive strength, and they’re generally best suited to structures with light transverse loading when the cores remain unfilled. Filling some or all of the cores with concrete, stone or steel reinforcement offers much greater tensile and lateral strength to structures.

Advantages

The use of materials such as brick and stone can increase the thermal mass of a building, giving increased comfort in the heat of summer and the cold of winter and can be ideal for passive solar applications.

Brick typically will not require painting and so can provide a structure with reduced life-cycle costs, although sealing appropriately will reduce potential spalling due to frost damage. Concrete block of the non-decorative variety generally is painted or stuccoed if exposed.

The appearance, especially when well crafted, can impart an impression of solidity and permanence.

Is very heat resistant and thus will provide good fire protection

Disadvantages

Extreme weather may cause degradation of the surface due to frost damage. This type of damage is common with certain types of brick, though relatively rare with concrete block. If non-concrete brick is to be used, care should be taken to select bricks suitable for the climate in question.

Masonry must be built upon a firm foundation to avoid potential settling and cracking. If expansive soils are present, this foundation may need to be quite elaborate and the services of a qualified structural engineer may be required.

The high weight increases structural requirements, especially in earthquake prone areas.

Structural limitations

Masonry boasts an impressive compressive strength but is much lower in tensile strength unless reinforced. The tensile strength of masonry walls can be strengthened by thickening the wall or by building masonry “piers at intervals. Where practical, steel reinforcement also can be introduced vertically and/or horizontally to greatly increase tensile strength, though this is most commonly done with poured walls.

Veneer masonry

Brick veneer construction has strength imparted by a framework of wood or a rough masonry wall of other material over which is placed a layer of bricks for weatherproofing and providing a finished appearance. The brick veneer wall is connected to the structural walls by “brick ties”, metal strips that are attached to the structural wall as well as the mortar joints of the brick veneer wall. There typically is an air gap between the brick veneer wall and the structural wall. As clay brick is not completely waterproof, the structural wall has a water-resistant surface and weep holes are left at the base of the brick veneer wall to ventilate the air gap.

Most insulated buildings that utilize concrete block, brick, veneers or some combination thereof feature interior insulation in the form of fiberglass batts between wooden wall studs or rigid insulation boards covered with plaster or drywall. In most climates, this insulation is much more effective on the exterior of the wall, allowing the building interior to take advantage of the aforementioned thermal mass of the masonry. This technique does require however, some sort of weather-resistant exterior surface over the insulation and, consequently, is generally more expensive.

Dry set masonry
The strength of a masonry wall is not entirely dependent on the bond between the building material and the mortar; the friction between the interlocking blocks of masonry is often strong enough to provide a great deal of strength on its own. The blocks sometimes have grooves or other surface features added to enhance this interlocking, and some dry set masonry structures forego mortar all together.

Solid masonry

Solid masonry, without steel reinforcement, tends to have very limited applications in modern wall construction. While such walls can be quite economical and suitable in some applications, susceptibility to earthquakes and collapse is a major issue. Solid unreinforced masonry walls tend to be low and thick as a consequence.

Brick

Solid brick masonry is made of two or more layers of bricks with the units running horizontally bound together with bricks running transverse to the wall. Each row of bricks is known as a course. The pattern of headers and stretchers employed gives rise to different bonds such as the common bond, the English bond, and the Flemish bond. There are no significant utilitarian differences between most bonds, but the appearance of the finished wall is affected. Vertically staggered bonds tend to be somewhat stronger and less prone to major cracking than a non-staggered bond.

Uniformity and rusticity

The selection of the brick used, especially for color, will affect the appearance of the final surface. In buildings built during the 1970’s, a high degree of uniformity of brick and accuracy in masonry was typical. In later periods, this style was thought to be too sterile, so attempts were made to emulate older, rougher work. Some brick surfaces are made to look particularly rustic by including “burnt” bricks, which have a darker color or an irregular shape. Others may use antique salvage bricks, or new bricks may be artificially aged by applying various surface treatments. The attempts at rusticity of the late 20th century have been carried forward by masons specializing in a free, artistic style, where the courses are intentionally not straight, instead weaving to form more organic impressions.

Serpentine masonry

A crinkle-crankle wall is a brick wall that follows a serpentine path, rather than a straight line. This type of wall is more resistant to toppling than a straight wall; so much so that it may be made of a single thickness of unreinforced brick and so despite its longer length may be more economical than a straight wall.

Concrete block

Blocks of cinder concrete, ordinary concrete or hollow tile are generically known as Concrete Masonry Units. They usually are much larger than ordinary bricks and so are much faster to lay for a wall of a given size. Furthermore, cinder and tile blocks have much lower water absorption rates than brick. They often are used as the structural core for veneered brick masonry, or are used alone for the walls of factories, garages and other “industrial” buildings where appearance is not a significant factor. Such blocks often receive a stucco surface for decoration. Surface-bonding cement sometimes is used in this application and can impart extra strength to a block wall.

The primary advantage of concrete blocks in comparison to smaller clay-based bricks is that a CMU structure can be reinforced by either fully grouting the voids or inserting vertical lengths of rebar and using grout to hold them in place. In this manner, a CMU wall can be built much stronger than typical masonry walls.

Some concrete blocks are colored, and some employ a split face, a technique that results in two blocks being manufactured as one unit and later split into two. This gives the blocks a rough face replicating the appearance of natural, quarried stone, such as brownstone. For applications such as roadway sound control walls, the patterns may be complex and even artistic.

Decorative CMUs have gained in popularity also, with units featuring a glazed, burnished or glossy finish emerging as innovative new options in interior veneers. Decorative CMUs most often appear in financial institutions, schools and other municipal or professional settings where an aesthetic-but-durable, or a virtually marbled product, is appropriate. Such blocks usually have a smooth finish and can have a visible internal aggregates, a solid uniformly colored glaze, or a visible aggregates protected by a clear sealant.

A-Jacks

A-jacks are high stability, concrete 6-pronged armor units designed to interlock into a flexible, highly permeable matrix. They can be installed either randomly or in a uniform pattern. They look like giant 3-foot versions of the metal jacks kids play with. In the uniform placement pattern, each unit is in contact with the six adjacent units, providing high stability. They are patterned after the buckyball model.

Stone

Stone blocks used in masonry can be “dressed” or “rough.” Stone masonry utilizing dressed stones is known as ashlars’ masonry, whereas masonry using irregularly shaped stones is known as rubble masonry. Both rubble and ashlars’ masonry can be laid in courses through the careful selection or cutting of stones, but a great deal of stone masonry is uncoursed.

Sometimes “river rock” is used as a veneer. This type of material is not favored for solid masonry as it requires a great amount of mortar and can lack intrinsic structural strength.

Growing in popularity among builders and homeowners are manufactured-stone veneers. Companies such as many architects and developers have found manufactured stone veneers to be the most cost effective and environmentally sound choice for the building’s exterior walls as well as many areas throughout the project, such as interior walls and landscape areas.

Natural stone veneers such as those produced by Arnold Stone are also used by many builders and masons but in a world of diminishing natural resources, the decision to use natural veneers is one that is important on each project.

Gabions

Gabions are rectangular wire baskets, usually of zinc protected steel that are filled with fractured stone of medium size. These will act as a single unit and are stacked with setbacks to form a revetment or retaining wall. They have the advantage of being both well drained and flexible, and so resistant to flood, water flow from above, frost damage, and soil flow. Their expected useful life is only as long as the wires they are composed of and if used in severe climates must be made of appropriate corrosion-resistant wire.

Bagged concrete

A low grade concrete may be placed in woven plastic sacks similar to that used for sandbags and then emplaced. The sacks are then watered and the emplacement then becomes a series of artificial stones that conform to one another and to adjacent soil and structures. This conformation makes them resistant to displacement. The sack becomes non-functional and eventually disintegrates. This type of masonry is frequently used to protect the entrances and exits of water conduits where a road passes over a stream or dry wash. It is also used to protect stream banks from erosion, especially where a road passes close by.

Masonry Training

Stonemasonry is one of the oldest professions in the history of construction. As such is regarded as a traditional skill, and is one, which is in heavy demand.

Prospective stonemasons will learn the profession through apprenticeships or a traineeship that will last 3 to 4 years. There are City & Guilds stonemasonry courses available that combine college based theory training with practical learning.

If you are looking for a mason to help you build something wonderful, the best place to search is on Repairfinders.com. On this site, you will only find the very best masons in the business, and ones that are in your area. All it takes is a couple minutes of your time, to browse our extensive list of businesses in your area, and when you find the one that is the best for you, contact them, and they will me more than willing to assist you with your needs. On repairfinders.com, you will never be disappointed with the service. Have a good night folks! -Jack

Carpentry, a profession for the truely t...

repairfinder — Thu, 25 Sep 2008 20:54:12 +0200

Hey, folks at home, it is your old pal Jack! Carpentry is a very interesting profession. It requires skill, creativity, honesty, and reliability. It is a great career choice for anyone who is willing to put the work into being good at this. It pays well, and once you take the proper classes, and get your certificates and license, you can make your own hours. So let us talk a little about this today. Carpenters are involved in many different kinds of construction, from the building of highways and bridges to the installation of kitchen cabinets. Carpenters construct, erect, install, and repair structures and fixtures made from wood and other materials.

Each carpentry task is somewhat different, but most involve the same basic steps. Working from blueprints or instructions from supervisors, carpenters first do the layout-measuring, marking, and arranging materials-in accordance with local building codes. They cut and shape wood, plastic, fiberglass, or drywall using hand and power tools, such as chisels, planes, saws, drills, and sanders. They then join the materials with nails, screws, staples, or adhesives. In the last step, carpenters do a final check of the accuracy of their work with levels, rules, plumb bobs, framing squares, and surveying equipment, and make any necessary adjustments.

When working with prefabricated components, such as stairs or wall panels, the carpenter’s task is somewhat simpler because it does not require as much layout work or the cutting and assembly of as many pieces. Prefabricated components are designed for easy and fast installation and generally can be installed in a single operation.

Some carpenters do many different carpentry tasks, while others specialize in one or two. Carpenters who remodel homes and other structures, for example, need a broad range of carpentry skills. As part of a single job, for example, they might frame walls and partitions, put in doors and windows, build stairs, install cabinets and molding, and complete many other tasks. Because these carpenters are so well trained, they often can switch from residential building to commercial construction or remodeling work, depending on which offers the best work opportunities.

Carpenters who work for large construction contractors or specialty contractors may perform only a few regular tasks, such as constructing wooden forms for pouring concrete, or erecting scaffolding. Some carpenters build tunnel bracing, or brattices, in underground passageways and mines to control the circulation of air through the passageways and to worksites. Others build concrete forms for tunnel, bridge, or sewer construction projects.

Carpenters employed outside the construction industry perform a variety of installation and maintenance work. They may replace panes of glass, ceiling tiles, and doors, as well as repair desks, cabinets, and other furniture. Depending on the employer, carpenters install partitions, doors, and windows; change locks; and repair broken furniture. In manufacturing firms, carpenters may assist in moving or installing machinery.

Work environment. As is true of other building trades, carpentry work is sometimes strenuous. Prolonged standing, climbing, bending, and kneeling often are necessary. Carpenters risk injury working with sharp or rough materials, using sharp tools and power equipment, and working in situations where they might slip or fall. Although many carpenters work indoors, those that work outdoors are subject to variable weather conditions.

Most carpenters work a standard 40 hour week. Hours may be longer during busy periods. Carpenters learn their trade through formal and informal training programs. Between 3 and 4 years of both on-the-job training and classroom, instruction usually is needed to become a skilled carpenter. There are a number of ways to train, but a more formal training program often improves job opportunities.

Education and training. Learning to be a carpenter can start in high school. Classes in English, algebra, geometry, physics, mechanical drawing, blueprint reading, and general shop will prepare students for the further training they will need.

After high school, there are a number of different ways to obtain the necessary training. Some people get a job as a carpenter’s helper, assisting workers that are more experienced. At the same time, the helper might attend a trade or vocational school, or community college to receive further trade-related training and eventually become a carpenter.

Some employers offer employees formal apprenticeships. These programs combine on-the-job training with related classroom instruction. Apprentices usually must be at least 18 years old and meet local requirements. Apprenticeship programs usually last 3 to 4 years, but length varies with the apprentice’s skill.

On the job, apprentices learn elementary structural design and become familiar with common carpentry jobs, such as layout, form building, rough framing, and outside and inside finishing. They also learn to use the tools, machines, equipment, and materials of the trade. In the classroom, apprentices learn safety, first aid, blueprint reading, freehand sketching, basic mathematics, and various carpentry techniques. Both in the classroom and on the job, they learn the relationship between carpentry and the other building trades.

The number of apprenticeship programs is limited, however, so only a small proportion of carpenters learn their trade through these programs. Commercial and industrial building contractors with union membership offer most apprenticeships.

Some people who are interested in carpentry careers choose to get their classroom training before seeking a job. There are a number of public and private vocational-technical schools and training academies affiliated with unions and contractors that offer training to become a carpenter. Employers often look favorably upon these students and usually start them at a higher level than those without the training.

Other qualifications. Carpenters need manual dexterity, eye-hand coordination, physical fitness, and a good sense of balance. The ability to solve arithmetic problems quickly and accurately also is required. In addition, military service or a good work history is viewed favorably by employers.

Certification and advancement. Carpenters who complete formal apprenticeship programs receive certification as journeypersons. Some carpenters earn other certifications in scaffold building, high torque bolting, or pump work. These certifications prove that carpenters are able to perform these tasks, which can lead to additional responsibilities.

Carpenters usually have more opportunities than most other construction workers do to become general construction supervisors because carpenters are exposed to the entire construction process. For those who would like to advance, it is increasingly important to be able to communicate in both English and Spanish in order to relay instructions and safety precautions to workers; Spanish-speaking workers make up a large part of the construction workforce in many areas. Carpenters may advance to carpentry supervisor or general construction supervisor positions. Others may become independent contractors. Supervisors and contractors need good communication skills to deal with clients and subcontractors. They should be able to identify and estimate the quantity of materials needed to complete a job and accurately estimate how long a job will take to complete and what it will cost. Average job growth, coupled with replacement needs, create a large number of openings each year. Job opportunities should be best for those with the most training and skills.

Employment change. Employment of carpenters is expected to increase by 10 percent during the 2006-16 decade, about as fast as the average for all occupations. The need for carpenters should grow as construction activity increases in response to demand for new housing and office and retail space, and for modernizing and expanding schools and industrial plants. A strong home remodeling market also will create demand for carpenters. Moreover, construction of roads and bridges as well as restaurants, hotels, and other businesses will increase the demand for carpenters in the coming decade.

Some of the demand for carpenters, however, will be offset by expected productivity gains resulting from the increasing use of prefabricated components and improved fasteners and tools. Prefabricated wall panels, roof assemblies, and stairs, as well as prehung doors and windows can be installed very quickly. Instead of having to be built on the worksite, prefabricated walls, partitions, and stairs can be lifted into place in one operation; beams and, in some cases, entire roof assemblies, are lifted into place using a crane. As prefabricated components become more standardized, builders will use them more often. In addition, improved adhesives are reducing the time needed to join materials, and lightweight, cordless, and pneumatic tools-such as nailers and drills-will all continue to make carpenters more productive. New and improved tools, equipment, techniques, and materials also have made carpenters more versatile, allowing them to perform more carpentry tasks.

Job prospects. Job opportunities should be best for those with the most training and skills. Job growth and replacement needs for those who leave the occupation create a large number of openings each year. Many people with limited skills take jobs as carpenters but eventually leave the occupation because they dislike the work or cannot find steady employment.

Carpenters with all-around skills will have better opportunities for steady work than carpenters who can perform only a few relatively simple, routine tasks. Carpenters can experience periods of unemployment because of the short-term nature of many construction projects, winter slowdowns in construction activity in northern areas, and the cyclical nature of the construction industry.

Employment of carpenters, like that of many other construction workers, is sensitive to the fluctuations of the economy. Workers in these trades may experience periods of unemployment when the overall level of construction falls. On the other hand, shortages of these workers may occur in some areas during peak periods of building activity.

Job opportunities for carpenters also vary by geographic area. Construction activity parallels the movement of people and businesses and reflects differences in local economic conditions. The areas with the largest population increases will also provide the best opportunities for jobs as carpenters and for apprenticeships for people seeking to become carpenters. Therefore, as you can see it takes a lot of skill to become a carpenter. The only place to find the best in the field is at Repairfinders.com. We have the best in the business listed and you could never go wrong. Do not believe me check it out for yourself!

Do you know the difference between Cemen...

repairfinder — Thu, 18 Sep 2008 20:47:36 +0200

Today is such a beautiful day! I have always found Thursdays to be a bit boring, but today is such a nice day. I figured that since I am in such a good mood, we could do something “educational”. Instead of giving you the inside scoop today, I am going to give you information. Doesn’t that sound fun? Well let us get to it. Be prepared to learn a lot, because I know you do not know much about cement.

Many people talk about cement when they mean concrete.

Cement is a fine-grained compound that turns into a solid when mixed with water. Cement is used to bind mixtures of materials into a composite solid.

Concrete is a mixture of cement, sand and gravel. That is, cement is the glue of concrete. Now that we have made that clear, let us talk about cement. Cement begins with lime.

Lime, the First Cement

Lime is a substance used since ancient times to make useful things like plaster and mortar. Lime is made by burning, or calcining, limestone-and that is how limestone gets its name. Chemically, lime is calcium oxide (CaO) and is made by roasting calcite (CaCO3) to drive off carbon dioxide (CO2). That CO2, a greenhouse gas, is produced in great quantities by the cement industry.

Lime is also called quicklime or calx (from Latin, where we also get the word calcium). In old murder mysteries, quicklime is sprinkled on victims to dissolve their bodies because it is very caustic.

Mixed with water, lime slowly turns into the mineral portlandite in the reaction CaO + H2O = Ca(OH)2. Lime is generally slaked, that is, mixed with an excess of water so it stays fluid. Slaked lime continues to harden over a period of weeks. Mixed with sand and other ingredients, slaked lime cement can be packed between stones or bricks in a wall (as mortar) or spread over the surface of a wall (as render or plaster). There, over the next several weeks or even years, it reacts with CO2 in the air to form calcite again-artificial limestone!

Concrete made with lime cement is known from archaeological sites in both the New and Old World, some more than 5000 years old. It works extremely well in dry conditions. It has two drawbacks: Lime cement takes a long time to cure, and while the ancient world had lots of time, today time is money.

Lime cement does not harden in water but stays soft, that is, it is not a hydraulic cement. So, there are many situations where it cannot be used.

Ancient Hydraulic Cement

The Pyramids of Egypt are said to contain a hydraulic cement based on dissolved silica. If that 4500-year-old formula can be confirmed and revived, it would be a great thing. However, today’s cement has a different pedigree that is still quite ancient.

Around 1000 BCE, the ancient Greeks were the first to have a lucky accident, mixing lime with fine volcanic ash. Ash can be thought of as naturally calcined rock, leaving silicon in a chemically active state like the calcium in calcined limestone. When this lime-ash mixture is slaked, a completely new substance is formed: calcium silicate hydrate or what cement chemists call C-S-H (approximately SiCa2O4 · xH2O).

C-S-H is still a mysterious substance today, but we know it is an amorphous gel without any set crystalline structure. It hardens fast, even in water. In addition, it is more durable than lime cement.

The ancient Greeks put this new cement to use in new and valuable ways, building concrete cisterns that survive to this day. But Roman engineers mastered the technology and constructed seaports, aqueducts and temples of concrete as well. Some of these structures are as good as ever today, two thousand years later. However, the formula for Roman cement was lost with the fall of the Roman Empire.

Modern Hydraulic Cement

While lime cement continued in use throughout the Dark and Middle Ages, true hydraulic cement was not rediscovered until the late 1700s. English and French experimenters learned that a calcined mixture of limestone and claystone could be made into hydraulic cement. One English version was dubbed “Portland cement” for its resemblance to the white limestone of the Isle of Portland, and the name soon extended to all cement made by this process.

Shortly thereafter, American makers found clay-bearing limestone’s that yielded excellent hydraulic cement with little or no processing. This cheap natural cement made up the bulk of American concrete for most of the 1800s, and most of it came from the town of Rosendale in southern New York.

Rosendale was practically a generic name for natural cement, although other manufacturers were in Pennsylvania, Indiana and Kentucky. Rosendale cement is in the Brooklyn Bridge, the U.S. Capitol building, most 19th-century military buildings, the base of the Statue of Liberty and many other places. With the rising need to maintain historic structures using historically appropriate materials, Rosendale natural cement is being revived.

True Portland cement slowly gained popularity in America as standards advanced and the pace of building quickened. Portland cement is more expensive, but it can be made anywhere the ingredients can be assembled instead of relying on a lucky rock formation. It also cures faster, an advantage when building skyscrapers a floor at a time. Today’s default cement is some version of Portland cement.

Modern Portland Cement

Today limestone and clay-containing rocks are sintered-roasted together at nearly melting temperature-at 1400° to 1500°C. The product is a lumpy mixture of stable compounds called clinker. Clinker contains iron (Fe) and aluminum (Al) as well as silicon and calcium, in four main compounds:

Alite (Ca3SiO5)
Belite (Ca2SiO4), known to geologists as larnite
Aluminate (Ca3Al2O6)
Ferrite (Ca2AlFeO5)

Clinker is ground to powder and mixed with a small amount of gypsum, which slows down the hardening process. And that is Portland cement.

Making Concrete

Cement is mixed with water, sand and gravel to make concrete. Pure cement is useless because it shrinks and cracks; it is also much more expensive than sand and gravel. As the mixture cures, four main substances are produced:

C-S-H
Portlandite
Ettringite (Ca6Al2(SO4)3(OH)12 26H2O; includes some Fe)
Monosulfate ([Ca2(Al,Fe)(OH)6] (SO4,OH,etc) xH2O)

The details of all this are an intricate specialty, making concrete as sophisticated a technology as anything in your computer. Yet basic concrete mix is practically stupid proof, simple enough for you and me to use. You see though we are smarter than that, we will not go around messing with cement and concrete mixes, because we know we should leave that to the professionals. So if you need a professional, check out repairfinders.com where they have only the best in the business, and you will never be let down. Jack is over and out.

Do you know what it takes to be a genera...

repairfinder — Mon, 15 Sep 2008 21:21:09 +0200

Hello folks at home. I hope yall are having a wonderful day, wherever you may be today. I was thinking about children’s today, and how they all want to be musicians, actors, and fashion & graphic designers. But what I would like to know is whatever happened to the days, when kids wanted to be like their pa’s and become plumbers, engineers, carpenters, and such? Today let us talk about general contractors and so on; it is a nice aspiration for anyone who wants to live a comfortable life.

General contractors coordinate and supervise the work at construction sites from early development to final product. They own the contracting firms in charge of construction, or they may be salaried employees of property owners and developers. Sometimes they have different titles, such as construction managers or project engineers. While some general contractors undertake many kinds of work, most of them specialize in one type and size of construction project. Residential contractors may oversee some commercial buildings, for instance, but they rarely take on large-scale public-works projects, such as bridges, sewage systems, and industrial sites.

Before contractors begin a project, they must submit a bid or price quote to the individual, company, or government agency that will pay for it. To make an accurate bid, contractors study the building plans and specifications while keeping in mind material, labor, and safety considerations. They may hire a cost estimator to do this job. The lowest bid is usually, but not always, accepted. Other factors, such as the quality of a contractor’s past work, may be taken into account. Construction projects are usually a series of tasks, each completed by a different subcontractor. The bulldozer operators clear and level the land, so the structural steelworkers or the carpenters can put up the skeleton of the building. General contractors hire or supervise the hiring of the subcontractors who do each of the many tasks. Contractors must communicate well because they need to motivate many different types of people.

Contractors either own or rent the equipment needed for the job. They contact companies that supply concrete, steel, electrical equipment, lumber, and other building materials to arrange shipments, and they get the necessary permits and licenses for construction and see that building codes and safety regulations are followed. At all steps in the construction, contractors track and control expenditures. Depending on the job, contractors may have several people to help with management details. They may hire estimators to help prepare bids, expediters to oversee material shipments, various job supervisors, office staff, and others. However, contractors shoulder the full responsibility and risk involved. On repairfinders.com, you can find general contractors, in your area, so if you need a job done they can do it for you! Jack is over and out yall.