Blog Archives

ROOFS

Posted by on 21/ 11/ 15

I was in an office-supply house recently when a customer brought in a type­writer for repair. Folks were joking with him, wondering what he was doing with a typewriter in this time of computers. These days, in the world of roof trusses, cutting and building simple gable roofs on site has almost gone the way of the typewriter. Nevertheless, I still love the challenge of cutting and building (we call it stacking here on the West Coast) conventional stick-built roofs, whether the roof is a simple gable or a complex one with many different ridges, hips, and valleys coming together from every direction.

Now, of course, even the most compli­cated roof can usually be made by a truss company and shipped to the site ready to install...

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Cool Design for a Comfortable Home

Posted by on 21/ 11/ 15

■ BY SOPHIE PIESSE

Cool Design for a Comfortable HomeПодпись: Passive in practice. The author's house demonstrates passivecooling strategies that include east-west orientation, overhangs formed both by eaves and a second-floor balcony, and a vertical design that promotes good ventilation.

I live in North Carolina, and I love the look on people’s faces when I tell them that I haven’t turned on my first-floor air­conditioning in 10 years. There’s always a pause, and then they lift their jaw off the floor and ask me, "Really? How?"

As an architect who designs new homes, renovations, and additions, I encourage my clients to explore options for passive heat­ing and cooling and energy-smart design before we ever look at mechanically assisted options. To make your house truly energy – efficient, you must design it with the goal of using as little energy as possible...

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Sweaters, Windbreakers, and Rain Gear

Posted by on 21/ 11/ 15

Don’t worry; we haven’t suspended our home­building work to look through the L. L. Bean® catalog. But what you already know about sweaters, windbreakers, and raincoats will help you understand the way sealing, insulating, and moisture-protection treatments work together in a house.

Start with a sweater and a windbreaker—just what you need to wear on a cold, windy day. A house exposed to frigid temperatures and icy winds also needs a sweater and a windbreaker. Insulation, exterior siding, and housewrap provide this protec­tion. In fact, housewraps like Tyvek and Typar act like a Gore-Tex® raincoat, blocking wind and water while still allowing vapor to pass through. This helps prevent moisture buildup, both in our clothing and inside the walls of a house.

As we work through the ste...

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Beyond Rome, The East And The Arab World

Posted by on 21/ 11/ 15

Beyond the Roman Empire – Persia and India

Between the Tigris, the Ganges, and the Oxus: multicultural influ­ences

The Indus valley had harbored the great “hydraulic” civilization of Harappa between the third and second millenia BC. This civilization would develop to have exchanges with the Mesopotamian millenia, and had extended its influence along the “lapis-lazuli route”, to the north of the Hindu Kush mountains in Bactria (Figures 1.3, 7.1). After the collapse of this civilization only the trading posts to the south remained, at and around the mouth of the Indus at Lothal...

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Constitutive Modelling and Partial Saturation, Suction Coupling, Water Interaction on Mechanical Behaviour

Posted by on 21/ 11/ 15

Routine pavement design is based on an elastic calculation, with a resilient modulus. The design criterion is, typically, a limit placed on the maximum vertical strain. More elaborated models take into account the irreversible behaviour, e. g.:

• The Chazallon-Hornych model is based on the Hujeux multi-mechanism yield surface improved by a kinematical hardening; and

• The Suiker and Mayoraz elasto-visco-plastic models evaluate the irreversible strains on the basis of an overstress (Perzyna theory) which is the distance be­tween the stress level and a visco-plastic potential.

Each of these elaborated models is then based on a yield surface, a potential surface, a limit surface, in all cases a surface typical of the granular soil mechanics, with a frictional mechanism, possibly a cap co...

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INSIDE

Posted by on 21/ 11/ 15

Sealing, Insulating, and Ventilating a House

The old house I was born in still stands out there on the prairie. When I was a child, the house was simply unheatable in the wintertime. We defi­nitely spent more dollars trying to heat the house than we did on the mort­gage. Nowadays, the house has new doors and windows, insulation in the ceiling, and a real heating system—not just an old iron stove in the kitchen. But there are still plenty of cracks and gaps in the walls for those ever­present western winds to howl through.

Thankfully, we don’t build houses like we used to. Today, there are materi­als and methods available that allow us to design and build energy-efficient houses that hold heat during the winter and keep it out during the summer.

But attaining high levels of comfort ...

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Effective Stress Approach

Posted by on 21/ 11/ 15

The constitutive models introduced in the previous sections express the constitutive stress-strain relation of the material. As soon as the water is involved, the material has to be considered as a multi-phase porous media with two phases: the solid matrix (for which we introduced the stress-strain constitutive relations) and the water phase. The two phases are coupled since the pressure acting in the water may affect the mechanical behaviour of the material. Also, the material deformation may modify the pressure in the water. Such hydro-mechanical coupling is well represented by
the Terzaghi effective stress concept for saturated conditions (when water is filling all the pores) (Terzaghi, 1943)...

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Unidirectional Slip Bases

Posted by on 21/ 11/ 15

Unidirectional slip bases for small sign supports consist of inclined slip bases, as shown in Fig. 7.18. The upper support piece is made from rolled-steel shapes, standard pipe, or structural tube. The base of the support assembly is inserted into a concrete footing to prevent movement of the anchor assembly.

The upward thrust obtained from the inclined slip base design is important to the proper action of a single-support sign system. The upward thrust causes the sign panel and support to rise and rotate when vehicle impact separates the mechanism. The sign panel and support stay together as a unit, which passes up and over the vehicle and lands behind it. This action is obtained only when the support is impacted from one direction...

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CEILING JOISTS FOR A GABLE ROOF

Posted by on 21/ 11/ 15

The saying, "They don’t build them like they used to," is often true when it comes to ceiling joists. And it’s just as well. I have remodeled many an old house that had ceiling joists that were sagging from the weight of time and heavy plaster. If you live in an old house,
look at your ceilings—especially in large rooms—-and check to see if they sag in the center.

Once the walls have been plumbed and lined, ceiling joists can be nailed to the tops of the walls in preparation for installing roof rafters (see the drawing on p. 132). In factory-built roof trusses, joists are part of the truss (see Chapter б for more information on roof trusses). Joists nail to the top plates of the walls and help tie the house frame together...

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Sealing, Insulating, and Ventilating a House

Posted by on 21/ 11/ 15

THE OLD HOUSE I WAS BORN IN STILL STANDS out there on the prairie. When I was a child, the house was simply unbeatable in the wintertime. We definitely spent more dollars trying to heat the house than we did on the mortgage. Nowadays, the house has new doors and windows, insulation in the ceiling, and a real heating system— not just an old iron stove in the kitchen. But there are still plenty of cracks and gaps in the walls for those ever-present western winds to howl through.

Thankfully, we don’t build houses like we used to. Today, there are materials and methods available that allow us to design and build energy-efficient houses that hold heat during the winter and keep it out during the summer. But attaining high levels of comfort and energy efficiency is not always a simple feat...

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