Compared to other European capitals, Rome’s subway is far less developed. For years, Rome’s 2.8 million citizens relied solely on two scant subway lines that fell short of meeting the city’s transportation needs. The two lines don’t even connect and they do not come near to the historical city centre. Being one of the oldest cities in the world, the construction of a subway poses many difficulties. Rome is built upon a labyrinth of tunnels, catacombs, vaults, and ancient sewer systems.

During the construction of the first two subway lines in the 1950’s, each excavation exposed archaeological remains and the construction had to be stopped to allow the local archaeologists to check their significance. Alternate routes had to be thought-out and determined if the discovery proved valuable to the history of the Romans.

After years of funding shortfalls and decades of debate, work began on a third subway line. Now that the third subway line is under construction, it has been marked as an “archaeological survey” from the very beginning and great care is being taken. This new line will run through the very heart of the ancient city. It will be 24 kilometers (15 miles) in length and 25 to 30 metres (80 to 100 feet) below ground.

Finally, after many centuries, archaeologists are working together with construction workers to excavate beneath Rome’s central Piazza Venezia, only a few hundred yards from the Roman Forum.
Almost immediately, excavation revealed some spectacular finds. Just below the surface, excavators discovered building remnants from the renaissance that were torn down in the late 19th century.

They dug one layer deeper and this exposed Via Flamina, a medieval road that once traversed the city. And one layer below that, they discovered a herringbone pavement from the 8th century.
Beneath the Piazza Venezia and near the ancient Forum, workers discovered a sixth-century copper factory. The early factory consisted of small ovens used to work on copper alloys. Small copper ingots discovered at the scene were sent for analysis.

Also discovered were the foundations of a 16th century Renaissance palace, a Roman tavern, and a medieval kitchen complete with pots and pans used to heat sauce.

Even though 38 active digs now line the subway construction, most of the digs have not reached the earth strata that date back to Roman times, where plenty of surprises may yet await discovery.

With every new discovery, officials must decide whether to remove, destroy, or preserve the artefacts and/or site within the subway’s structure.

Officials deemed a Roman tavern from the Middle Ages acceptable for destruction, but they eliminated an entire subway stop near the Pantheon from after workers found the base of an imperial Roman public building. This will force tourists and citizens alike to walk further to reach the new, relocated subway stop.

Further along the tunnels, workers found a “looter’s hole.” During the Middle Ages, builders would tie themselves to a rope and drop down into a well-like shaft to roam the underground to collect bricks, rock, or marble from earlier centuries to use for new construction.

There isn’t an inch of Rome that doesn’t have some artifacts below the street. In 300 A.D., one-and-a-half million people inhabited Rome. If they were to bring to light everything they and subsequent generations owned and built, the streets of Rome would all have to be eliminated and the entire city preserved as an archaeological dig.

Like the Roman ingenuity of ancient times, Romans today have found a way to preserve the old while creating the new.

For more interesting articles about Italy or to visit the home page of author Mirella Patzer, visit http://www.mirellapatzer.com and http://bestofitaly.blogspot.com

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When planning and designing a new pergola one of the main construction considerations is selecting the type of roofing material you want for your pergola in line with your needs. There are a number of different types of roofing available including polycarbonate, colorbond steel, tiles and opening roofs.

The first point to consider when making your selection is that the more light you let in, the more heat comes in. The catch being of course, that you need more light in winter and less in summer. There are a few ways around this problem, firstly you can use a combination of polycarbonate and colorbond steel incorporating 2 or 3 sheets of polycarbonate inserts and having the rest of the pergola roof in colorbond steel. This will effectively still let the light in that you need and the pergola climate underneath will remain comfortably cool. Another alternative is to have colorbond steel on the west side of the pergola and polycarbonate sheeting on the other, if the pergola has a gable roof.

With the polycarbonates there are a number of different qualities and light/heat factors available. Some polycarbonates let more light in and others less heat. Within the Laserlite range, there are over 20 to choose from. Polycarbonate also comes in many profiles such as Greca, Roma, Trim deck and Multi-wall System.

If you have a larger budget then an opening roof may be ideal, in this instance you can control how much light and heat you let in. In winter you can get all the winter sun by angling the open blades towards the sun and in summer just close the roof off. In the event of rain whilst you are out, the rain sensor will automatically close the opening roof for you.

Another style of pergola roofing to consider is an insulated roof with polystyrene in the middle, a colorbond roof at the top and a stucco finish on the bottom. With excellent insulation properties this style of roofing is often used for cool rooms. Of all the pergola roof coverings this one will keep out the most heat. The only downside is that it’s extremely hard to install light panels into this type of roofing.

Depending on the type of materials and roof design of your pergola it’s often possible to change or reposition some of the roof sheets if your pergola is too dark or too hot.

Fortunately with the emerging trend of the sophisticated pergola in outdoor entertaining there are a large range of materials and colours in pergola roofing to enhance your existing facade and to compliment your entertaining style.

About the Author

Greg Jacobs

What would you think if we said that a home could have:

* Heating bills 35%-60% less.

* Weather resistance that will stand up to hurricane force winds, and is rated to withstand earthquakes.

* The ultimate fire resistance insofar that some insurance companies decide to give a 20% (or more) discount on a homeowners’ policy.

* Healthy indoor air quality, essentially free from dust and pollen.

* A guarantee to never get dry-rot, or be infested by termites or carpenter ants.

* Recycled material components that save in average 15 trees per home when constructed.

* Reduced exterior wall sound transmission by more than 65% so barking dogs, lawn mowers, and even airplanes are reduced to a whisper.

* The most amazing thing of all, is that this technology is available right here, right now and it costs only a little more than a conventional wood built house.

The Magic of ICF’s……

The big secret that more and more builders, architects, engineers and homeowners are beginning to uncover is the new advances in concrete homes constructed using Insulating Concrete Forms (ICF) construction technology.

Insulating Concrete Forms are lightweight, highly durable foam blocks or forms composed of an expanded or extruded polystyrene, and recycled materials.

Raw plastic beads are molded into one of several basic form types. Some of these forms look like hollow blocks that you stack and interlock like big “Lego’s”. Others use panels that are held at a constant distance apart by a series of plastic ties.

Either way, the product is stacked in the shape of your home, reinforcing steel is placed inside, and concrete poured in between to create a solid, structural wall.

The Insulating Concrete Forms remain in place after the concrete sets, and function as thermal and acoustical insulation, an air and vapor barrier, and exterior wall sheathing. Your finished wall is basically 6″ +/- of reinforced concrete with 2″-3″ of dense foam insulation inside and out, resulting in a rock solid, 12″ thick, super-wall!

The integral, permanent insulation allows builders to construct ultra efficient walls in a fraction of the time required to build walls out of wood or steel studs.

How is an ICF Home Construction More Environmentally-Friendly?

In so many ways; ICF home construction reduces the consumption of energy. These are the most air-tight homes on the market. The concrete absorbs solar heat and slowly releases it so heat is distributed evenly throughout the home. The average energy consumption reduction is 35-60% below conventional wood frame houses. The houses use fewer natural resources to heat them and they will last quite literally for centuries.

ICF walls conserve forest resources and their energy efficiency reduces fossil fuel consumption. It’s estimated a 2,000 square foot home saves up to 15 large trees when compared to conventional construction. Concrete is inert, non-toxic, and produced from abundant natural and recycled material.

Lower noise from the outside world and the air exchange system all contribute to a more peaceful and healthy environment for the occupants of an ICF home.

Disadvantages of ICF construction:

Cost; expect to pay 5-10% more for an ICF home depending on where you live.Where ICF homes are popular the cost will probably be a little cheaper.

Even though ICF construction is very durable and Code approved, it might take a little extra time to get your plans through the building department (unless they are familiar with the particular system that you are using).

ICF construction requires subcontractors to do certain tasks differently. Wiring, heating, plumbing, and drywall will be different than in traditional construction. This might cause prices to be higher or occasionally, difficulty in finding sub-trades that have experience working in an ICF home.

The ICF industry is growing rapidly, and in the last few years we have completed projects in many different townships and municipalities. There are very few building departments left in Southern Ontario where they are not familiar with the ICF building process.

Summary:

* ICF homes are a superior system to wood framed or steel framed homes.

* Once the exterior walls are poured they are ready for finishing (on the inside and out).

* They are extremely durable and they don’t cost much more than a traditional framed home.

* Finding subcontractors may be a challenge, but if you are planning to live in your home for many years, ICF homes are the only choice to make.

Harvey Juric, ICF Consultant and CEO of ICFhome.ca is a custom home builder in southern Ontario. He has been in the home construction industry for the past 30 years performing a wide variety of tasks related to the building trades. As one of the pioneers of the Insulated Concrete Form industry, he formed ICFhome.ca to take advantage of, at that time, emerging new construction techniques that promised stronger and better and more energy efficient homes. For more information about the model home, Insulated Concrete Forms or Radiant Floor Heating contact ICFhome.ca by telephone 705 533-1633, e-mail info@icfhome.ca, or visit their web site at http://ontario-home-builder.com, http://hotwaterplant.com or http://insulated-concrete.com

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