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EXPOSED RAKE WITH TRIM BOARD

Posted by on 22/ 11/ 15

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EXPOSED RAKE WITH TRIM BOARDEXPOSED RAKE WITH TRIM BOARD

Подпись: BOXED-IN RAKEEXPOSED RAKE WITH TRIM BOARD

Detail at Eave

The transition from soffited eave to rake can demand some carpentry heroics. Only when the soffit is ter­minated at the plane of the end wall is the detailing reasonably direct, requiring only that the end of the soffit space be finished. This situation may occur with an abbreviated rake (see below) or with an overhanging rake (see below and 148B). As shown below, the end of the soffit space may be finished with a pork chop or with a layered gable—a continuation of the gable-wall finish over the end of the soffit.

EXPOSED RAKE WITH TRIM BOARD

PORK CHOP WiTH ABBREVIATED RAKE (ALSO USED WITH OVERHANGING RAKE); VERGE RAFTER oR Trim BoARD LApS

pork chop. chop covers end of soffit space.

When the soffit extends beyond the plane of the end wall, the rear side ...

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Appliance Selection

Posted by on 22/ 11/ 15

Microwave Ovens

Microwave ovens emit high electromagnetic fields (EMFs). These ovens are designed to heat food by creating enough microwave en­ergy to vibrate molecules in the food until heat is produced. When microwave ovens are in use, magnetic fields extend out as far as 12 feet. The actual microwaves produced during oper­ation are supposed to be contained in the oven by internal shielding, but leaks can occur. If you decide to use a microwave oven, the fol­lowing suggestions will make using it safer:

• Maintain a distance of four to 12 feet from the microwave oven while it is in use. This is especially important for children, who might enjoy watching the food as it is cook­ing.

• Have your appliance professionally check­ed for microwave leakage on an annual basis...

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Computer Programs

Posted by on 22/ 11/ 15

Available computer programs accurately design lighting systems using photometric curves and data for various fixtures. Some programs allow the user to input items such as trees and other physical barriers that may interfere with the output from the light fixtures. These programs will calculate luminance, illuminance, and glare. Dirt and maintenance factors that depend on the environment of the fixture location and the type of fixture are also used in the calculations. Some of the programs are easy to operate and very user friendly whereas some require much more detail. Computer-generated drawing files can be imported into the program, thus allowing the use of available site and roadway plans without the necessity of compiling a new drawing...

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THE UNIFIED NUMBERING SYSTEM

Posted by on 22/ 11/ 15

Are you aware of the Unified Numbering System (UNS)? This is a system that is meant to correlate the many metal alloy numbering systems that are being used in our country. I could go into a long discussion on this, but I believe that a simple table will give you enough information for now. Figure 11.1 shows you the various categories of alloys. If you look to the left of the table, you will see letters. The letters are the beginning for understanding types of alloys. For example, if a rating starts with the letter C, it is referring to copper. Seeing a letter F at the beginning of a rating indicates cast-iron.

Подпись: ► sensible shortcutTHE UNIFIED NUMBERING SYSTEMMETRIC SIZES

Подпись:Metric sizes are common in many places of the world. Plumbers in the United States still work primarily with customary measurements in terms of inches...

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The Arab Occident Water in al-Andalus

Posted by on 22/ 11/ 15

The Arabs came not only from North Africa, but also from Arabia, Syria, Iraq, Yemen, and Egypt. In 711 they conquered Spain, a country that had been occupied by the Visigoths since the fall of the Roman Empire. They brought with them all the Oriental technologies for water management: the ancient shaduf the bucket chain or saqqya, the noria, and qanats. The Arabs preferred developments of more modest scale in the Mesopotamian tradition compared to the grand Roman hydraulic works. The great Roman dam-reservoirs like those of Proserpina and Cornalvo were apparently not brought back into service.

42

It is thought that the oldest Arab project is an overflow dam built at Cordova, the capital of the Umeyyade caliphate...

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Hydraulics and prosperity in the heart of the Arab world

Posted by on 22/ 11/ 15

Arab agriculture included exotic crops such as cotton, rice, and sugar cane in addition to traditional grains and fruits. Cotton was known in Mesopotamia since the time of the Assyrians, but was essentially undeveloped. These crops require considerable water, and therefore are grown in the large irrigable zones on the shores of the Khabur, the Euphrates, and the Tigris.[325] The Muslim world uses all known existing techniques to develop irrigation. This includes derivation canals from rivers and wadis, water-lifting machines, and even drip irrigation for young plants, a technique known since the 5th century and wonderfully described in an Arab work of the 12th century.[326] The shaduf is used to lift water out of rivers and canals, but on a small scale...

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Appliances and Magnetic Fields

Posted by on 22/ 11/ 15

All motorized equipment found in homes will generate magnetic fields when in operation. Some epidemiological studies have linked ex­posure to these magnetic fields with increased incidence of cancer, Alzheimer’s disease, and miscarriage. Magnetic fields from properly wired appliances drop off very quickly in an exponential relationship to your distance from them. These fields can be easily measured with a small handheld instrument called a gauss – meter, which allows the user to determine the safe distance from an appliance.

The US government has not yet set reason­able standards for safe exposure levels, nor has it taken a strong position regarding the health effects of magnetic fields...

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AND CUTTING DRYWALL

Posted by on 22/ 11/ 15

Handling drywall is a bit like waltzing: You can do it by yourself, but it’s not all that much fun.

For starters, carrying an cumbersome 70-lb. panel around a work site is a two-person job. Both of you should be on the same side of the panel, same hand supporting the bottom edge, same hand balancing the top. (Imagine ballet dancers in a line.) As you walk, lean the upper part of the panel against your shoulder.

Hanging ceilings is definitely a two-person job, especially if you’re hanging longer panels to minimize joints. Once the two (or three) of you tack up a ceiling panel, one of you can finish attaching it, while another measures or cuts the next piece.

Measuring isn’t difficult, but you need to be aware of framing quirks...

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Transient Effects: The Time Dimension

Posted by on 22/ 11/ 15

The time dimension appears in the form of a first order time derivative in the consti­tutive mechanical model (Eqs. 11.3, 11.4) and in the diffusion problems though the storage term (Eq. 11.6). We will here discuss the time integration procedure and the accuracy and stability problems that are involved.

11.2.6.1 Time Integration – Diffusion Problems

The period to be considered is divided into time steps. Linear development of the basic variable with respect to the time is generally considered within a time step:

t — tA tB — t

p = – PB + – B PA (11.26)

tB — tA tB — tA

where the subscripts A, B denote, respectively, the beginning and the end of a time step. Then the pressure rate is:

dp _ Pb – Pa _ A p dt tB — tA At

This time discretisation is equivalent to a finite difference scheme...

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ESTIMATING MATERIALS

Posted by on 22/ 11/ 15

Start by consulting local building codes. They’ll specify the type, thickness, and number of drywall layers you must install throughout the house.

It’s possible to estimate drywall materials from a set of blueprints, but even the pros prefer to walk the job, measuring walls and ceilings and noting where using longer panels will minimize joints. That way, you get exactly the panel lengths you need.

As you walk through the rooms, record your findings on J4-in. graph paper. Use one sheet of paper per room, letting each square equal 1 ft. Then, when your materials arrive, you’ll know which room gets what.

1. Start by measuring the width and length of each room. In general, think in 2-ft. increments. That is, if a wall is 10 ft. 6 in. long, plan to buy 12-ft...

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