YES or NO. Let's think about this. There are several factors that determine the proportion of how roof(s) and attic(s) are in relationship with each other. The following items are important to consider, before reaching a firm conclusion:
CLIMATE
We are living in a period of a changing climate - Global Warming,
The winter of 1999-2000 saw the Greater Toronto, experience
83 "Freeze-Thaw Cycles". Up until the past 3 or 4 winters,
the average for this Cycle, was 17-20. This difference is
playing havoc with heated buildings. We would be far better
off, if the temperature would go below freezing, around the
middle of December . and stay there until March l.
BUILDING ENVELOPE
On an average 1 or 2 Storey House, the "building envelope",
does not include the ROOF - It is simply an umbrella - shedding
water off the structure. The Building Envelope is any barrier
- floor, wall or ceiling - that separates heated space from
unheated space, This is also, where air barriers, vapour barriers
and insulation are supposed to be. When any or all of these
components are weak, houses become very susceptible to moisture,
draft and even mould problems. The more "visible" upgrades
- WINDOWS & DOORS; and "mechanical" upgrades - FURNACES
& AIR CONDITIONERS; are completed, the more the "invisible"
ATTIC, becomes the "weak link". Unfortunately, because attic(s)
are out-of-sight, they are usually out-of-mind - until moisture,
mildew, or black mould, appear.
STYLE OF HOUSE
As architects and designers create more interesting and aesthetically
pleasing, exterior elevations and the resulting, complicated
roof lines, the Physical Function of a house becomes more
complicated as well. Too often, the necessary ventilation
is ignored, as appearance takes precedent. When the Laws of
Physics are overlooked, a heated structure becomes a potential
disaster, waiting to happen, We have the knowledge and the
technology to build houses properly, but too often, "design
is more important than function". Even, older, simple designs
have huge potential problems. In particular, double-brick
structures are vulnerable to magnified problems, because they
don't usually have Soffit/Overhang, intake-air ventilation.
Cape Cod style houses are among the most susceptible, with
the additional Side Attics and Sloped Ceilings.
EXPOSURE TO WEATHER
Which direction is the main part of the structure facing?
How much exposure is there, to the sun? Do trees shade the
lot? Do tree branches and leaves, overhang the roof?
PREMATURE WEATHERING OF ASPHALT SHINGLES
If you have bean in the house for a number of years and/or
the roof is 8-10 years old are the shingles showing signs
of deterioration, earlier than they should? This may occur
in a particular area or overall. The south and west
surfaces wear out more quickly, due to the increased exposure
to the sun. However, many times other areas will show more
wear, due to inferior attic conditions". When was the Attic
last inspected? What type of insulation do you have? Has it
been upgraded in the last 20 years? [Attic Insulation should
be in the range of a "true- R40, value.] Is there "black mould"
appearing on the underneath of the wood roof deck? Is the
Attic warm and/or humid, on a cold day? Are there any Kitchen
Fans or Washroom Exhaust Fans, present in your house? Where
are they transporting the warm moist air? Where is your Attic
Hatch? When was it last checked? When did the Attic last have
a plumber or electrician, present - during a renovation project?
Was the Attic inspected on completion of that work? How many
Ceiling Pot Lights are under/in the Attic Floor? How many
electrical boxes and wires penetrate the Attic Floor? How
do Plumbing Stack(s) penetrate the Attic Floor? How do Furnace
and Fireplace metal vents penetrate the Attic Floor? How is
the brick Chimney sealed? Do you have an old TV Tower connected
into the roof deck and do birds sit above the Roof here? Does
the TV Tower or overgrown trees and shrubs, provide an easy
path for squirrels and racoons to the Roof - and possibly
the Attic?
CONCLUSIONS
So, back to the original question. Are Roof(s) and Attic(s)
related? The correct answer is YES & NO depending on the
style of the house and the exposure to weather. The
quality of the Building Envelope controls the relationship
between Roof(s) and Aptly(s). Too often, the Roof gets blamed
for damage to the interior of the house, when in reality the
problem is not the Roof at all. In our climate - south-central
Ontario - it is time to be more aware of what, High School
Physics, teaches: [1] warm air always moves toward cold surfaces
or spaces; [2] when warm air connects with a cold surface,
the result is moisture- condensation and [3] when moisture
hits a surface that is below freezing temperature, it will
also freeze.
The most deluxe Roof Specification, using an adhesive-backed rubber membrane as eave protection will not prevent condensation in the Attic space, nor will it prevent ice damming. Far too often, we use Ice & Watershield or Heat Cables or Power Vents, as solutions to these symptoms. Ice & Watershield [properly installed], will certainly keep out external moisture, but will not prevent the rotting of the structural members in the Attic, due to internal moisture. Heat Cables are only a temporary solution, but will never keep up during prolonged periods of heavy snowfall and subfreezing conditions. They, along with Power Vents cost money to operate. When needed the most - to control condensation in winter - Power Vents are nothing more than an oversized static vent, unless the optional [extra cost], dehumidistat switch was installed. When the evidence of moisture is detected at wall-to-celling connections or on the wall between the ceiling and a window, please don't blame the Roof. Get to the "root of the problem" - inferior attic conditions. Until we start to use real, insulation and ventilation, making sure the weak point at the top plate of any exterior wall is protected, we will only continue to have Physics Problems, If we would learn to let the Building Envelope be the Building Envelope, and treat it as such, we could sit comfortably in our houses, without the undue worry and frustration that comes, when the weather turns nasty on us.
Many so-called Insulation Contractors, would rather blow-in insulation in a haphazard fashion - quickly and cheaply - than take the time to prepare for the to-be-added insulation. Most Builders and Renovators ignore "The House as a System Principle", only because they have never been trained properly. They are usually several years removed from High School Physics. Even professionals: Architects and Engineers don't get it - they are too busy thinking of a beautiful design, or making it way too complicated with theory: In reality, the topic is SIMPLE enough that even a teenager can understand.
Let the 'Practical Experience" of Let It Rain Inc.. have a chance at solving your Attic problems We have consultants who have studied and understand Building Science. We have become much more than just Roofing Specialists. We are Building Science Specialists, as well.
