|
|
|
|
Get a New Roof But Don't Add Any Ventilation?
(Jay Chan) wrote in message . com...
I would like to know whether this makes sense to replace the roof in
my house but don't put any ventilation to the roof.
I really don't know how the roof in my old house is currently being
ventilated. Our house doesn't have any soffit vent. The vents in both
gable ends are sealed off when the upper floor was converted into
living space. Consequently I have these problem from the roof:
- I feel that the upper floor in our house is very hot in summer.
- I have an ice-dam problem in the last winter (the roof is very low
pitch may also have something to do with this specific problem).
- When I examine the surface of the roof, I find that it is wavy in
some areas (something like 3" up and down). I feel that many areas in
the roof are soft or are bouncy. The house inspector told me the same
thing when he examined the house before I bought it.
I want to fix the roof. But when I got quotes from roofers, they
didn't mention anything about improving ventilation.
My questions a
- May be I am asking the wrong type of contractors to work on my
roof? I guess roofers only replace boards and shingles and don't deal
with other things (such as ventilation). What is the correct kind of
contractors that I should look for?
- What will happen if I replace the roof with new boards, new
membrane, and new shingles but not improving ventilation in anyway?
Will lack of any ventilation cause the new roof to quickly become
deteriorated? The roofers guarantee their work for 10 years though;
seem like they may know what they are talking about. I live in
northern New Jersey if this matters.
- Currently, the house has very low pitch, and the house doesn't have
any attic. I have a feeling that if I increase the pitch of the house
to make room for an attic, I may be able to greatly improve the
ventilation of the roof, and I may be able to run ductwork over the
attic for a future central air conditioning system. If I want to
improve the roof in this way, will this add too much load to the
structure of the house? The house used to be a Cape Cod style; and the
upper floor was bumped out to become a living area; I am afraid that
the structure of the house was not expecting a large attic. What kind
of contracters should I be looking for?
Thanks in advance for any info.
Jay Chan
Jay,
I suggest you look at Building Science Corporation web site for a
discussion of ventilation based on research. The style of presentation
is IMHO not reassuring, but I've seen work by some of the authors and
seen discussions by other building science folk that parallel much of
what is said on that site.
In the meantime, if I understand what you have, you may have to do
more than replace the roof covering. Research for more efficient
insulation and for some of the ways an unvented roof assembly is built
are important. It may be that the roofers you have spoken to recognize
that the roof assembly cannot be vented. I have notes from a Harvard
Graduate School of Design course that discuss the history of
ventilation requirements and the vague basis on which code
requirements for venting are based. If you are interested, let me
know.
Tom Baker
|