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Saturday, August 7, 2010

Should A Roof have Vents or Ventilation?

Just what really defines ventilation. Two camps exist in the debate. There are those who believe it is the movement of air through holes and slots placed everywhere and anywhere to let air move freely in and out of an attic and relieve pressure. The radicals believe ventilation is the forced movement of air in a vertical motion from the eaves to a common level of escape. On face value the first camp is correct in a basic sense and the second is just improved venting.
The bound paper dictionary is the best place to go to settle this debate but the young don't know how to use one. As a tool it does have advantages over the electronic version. You know we old guys like to complain and sometimes you whippersnappers will patiently simulate listening with behind the back gesturing and hand movements, whenever we're not looking and you get a chance. We know this because we were once where you are, in the dark. My complaint has been proffered both by Socrates and Hitler, that the youth are lazy and disrespectful. Both died for their beliefs. The youth won, for now. Just wait. You'll get here.
In my youth, it was a golden age, better than now. Everybody knows it. We had few videoesque diversions so we tore apart words instead. Today the dismemberment of words seems to be a lost art.
In the online version of the Merrian Webster Collegiate Dictionary I found this:
Main entry: Ventilation
Pronunciation: \ˌven-tə-ˈlā-shən\
Function: noun
Date: 1519

1 : the act or process of ventilating
2 a : circulation of air b : the circulation and exchange of gases in the lungs or gills that is basic to respiration
3 : a system or means of providing
fresh air

In my Smithsonian destined and well tattered copy of this glorious reference book I received as a freshman in high school in 1971, the same periodical had exactly the same information. No Wiki updates, no modifications, verbatim, verpunctuation, verditto.

The difference is that when you open a dictionary the words above and below the word du jour, vent, are readily visible:vent1, 2, and3, with sub-definitions within each, venter (a strange word worth looking up), ventilate, ventilator and a page or two of twists and turns containing the root "vent." A more intrinsic understanding of where this word can take us is gained by seeing the sister words that grew from the family of this word over time, from not just in English, but in all the Romantic and Germanic versions.

But just looking at the root "vent" tells us boo koos, from the French "beaucoup" (not your boyfriends roadster) about the word:

Main Entry: 1vent
Pronunciation: \ˈvent\
Function: verb
Etymology: Middle English, in part from 2vent, in part short for aventen to release (air), from Anglo-French aventer, alteration of Old French esventer to air, from es- ex- (from Latin ex-) + vent wind, from Latin ventus — more at wind
Date: 14th century

transitive verb 1 : to provide with a vent
2 a : to serve as a vent for b : discharge, expel c : to give often vigorous or emotional expression to ed her frustration on her coworkers>
3 : to relieve by means of a vent ed himself in a fiery letter to the editor>intransitive verb : to relieve oneself by venting something (as anger) s to the kids>

Love that last line but we must keep on track in our quest.
I would not have seen this if I hadn't pulled out the old leaf paper version. These barely post prehistoric devices known as books still can have an effect.
Notice the Latin origin, ventus for wind, which in Spanish is viento. A wind hole, or window, is ventana in Spanish. See the evolution?
The Middle English, aventen, from the Anglo French, was to release (air). (Did you read the definition's etymology?) So we know wind is a vertical movement except in rare cases like Flight 191, where it was in reverse. But ventilation is a derivative, not the kind that helped wreck the economy, of these older words, that lead to "vent,"reminiscent of Latin for wind.
Eureka, we have it. wind is the key. You see random holes let pressure out of a sealed attic but they cause no wind. Venting lets off pressure and ventilation causes wind.
Too many disparate exhaust holes confuse the air on where to leave. There is no magic that makes air hot go up. There are laws, more like theories, that cover this but the Venturi Effect shows that air will take the easiest path just like you or I, water or electricity, or heat and cold.
When uneven redundant holes or slits for vent ridge are made, there is no wind from bottom to top. There is wind from the second lowest to the highest hole, unless the second highest hole is too small, then the dynamics become completely incomprehensible.
The difference in an area as hot, humid, and sunny as the Dallas Fort Worth area can add up to thousands of dollars of A/C bills and repairs as well as a shortened roof, deck, insulation, and marriage life. Besides, your house may get hot too. Nobody is smiling when it's hot. We do have silly grins when we're freezing our tails off though. Dallas can get cold but the dynamics of retaining heat with insulation and not from covering your turbines should be easy to fathom.
If I'm only venting, I'm not maximizing my openings because I am only relieving pressure . If I'm ventilating I'm blowing wind. If I'm hyperventilating, well, get back.
Did you catch wind of that?
At least there were no break wind jokes.
How to Ventilate Attics
Why Roofers Can't Ventilate


Anonymous said...

Interesting use of the dictionary!

Roof Ventilators said...

Nice Blog about Roof Ventilator.
Roof ventilator is the motor-driven fan unit equipped with durable waterproof exhaust hood.

Roof Ventilators said...

Vary nice blog,
Roof vents and attic vents are an extremely important component of your home.