The roof of our 2000 sq. ft. bungalow (straightforward gable, 4/12
slope, no skylights) needs to be redone.

We've asked 5 contractors to give us an estimate. 4 are in the same
ballpark (i.e. $9,000 CDN), one is asking for TWICE that amount. He
says that the roof "felt soft" when he walked on it, so he's added
4700 sq.ft. worth of 1/2" plywood (to put on top of the existing one)
to his estimate. No other roofer mentioned "softness", but they did
indicate that, should they discover rotten wood underneath the
shingles, they would then charge us for the replacement (at $2.00 per
sq. ft.).

Well, I don't like surprises. Nor do I want to replace wood that
could still be in good condition.

Is there a way that I can assess the condition of the wood under the
shingles WITHOUT removing them? What signs should I be looking for in
the attic?

Also, is there a magic formula to calculate the size of a roof? None
of the roofers have quoted us the same size.

Any and all information relating to having one's roof redone is
appreciated.

On 28 Jul 2004 09:58:13 -0700, someone wrote:


Also, is there a magic formula to calculate the size of a roof? None
of the roofers have quoted us the same size.

It really doesn't mater so long as the quote is a price for the entire
roof (unless somebody was so far off that they could plausibly come
back and say uhhhh....).

Its by the s.f. but difficulty and waste is effected by shape,
valleys, hips, dormers, etc.

-v.

Just because I'm bored and I don't like con men.

Rectangular building, no dormers etc. no overhang of roof
width length sq ft floor 12/4 slope sq ft roof
feet feet "width"
25.0 80.0 2000 26.4
2108.2 ------- 25 x 80 = 2000 and 26.4 x 80 =
2108.2
30.0 66.7 2000 31.6 2108.2
35.0 57.1 2000 36.9 2108.2
40.0 50.0 2000 42.2 2108.2
45.0 44.4 2000 47.4 2108.2
50.0 40.0 2000 52.7 2108.2
55.0 36.4 2000 58.0 2108.2
60.0 33.3 2000 63.2 2108.2

So a price based on 2200-2300 esq. should be about right.

2$ can. per esq. = 32 x 2 = 64 $ per sheet, that's 30 $ max for 3/4" plywood
and 34 $ for labour
looks more than reasonable. Check your Totem or H.H. shop and that's no
contractor's price.

4700 esq. extra 1/2' plywood for 9000 $ = 1.90$ per esq. also looks
reasonable and even cheaper than the other ones, IF your whole roof had to
be replaced. And IF your roof is 4700 esq. I wouldn't walk on a 1/2 "
plywood! He'll replace all, or cover up the **** and has still 2500 esq.
left that's a nice 4.750$ profit on top of a very "good" price. Or think
about the weight of 4700 esq. plywood. A stack of 8' x 4' and over 6 foot
high. That's about 7000+ pounds of extra weight on your roof.

To calculate for your self. Slope 4" per 12" means the slope length of 1
foot (12") = according Pythagoras.
4² + 12² = slope length ² or 16 + 144 = 160 = slope length ². So the slope
length = sq.root 160 = 12.65 ".

Same but easier, for every foot you measure horizontally you add 5/8" extra
for the slope length.

To check the existing roof in the attic is easy, you need a flashlight and a
screwdriver. Look for water damage, mould or fungi.
Most chance at the lower parts of the roof, inside corners and the ridge.
And of course every opening for vents, chimney etc.
Be careful there might be wasp nests etc.
When in doubt count the sheets of plywood that need to be replaced and you
have your total price. (plywood 8 x 4 = 32 esq.)

The (a bit more expensive) contractor makes some extra money on the side, as
he will cover the whole roof with a new sheet he doesn't have to clean it
like the others will have to. You must have a dark 2000 esq. house with an
enormous overhang to get to that 4700 esq. roof.
Make sure the others remove the old sheets and replace, instead of the easy
way, wiping the dirt under the carpet and wait till the next one finds the
trouble.

Ever thought about doing it yourself? It's fun, 4/12 slope isn't that bad to
walk on. A bored student in need for cash might be willing to remove the old
ones and carry the new singles up. While he is busy you can have a nice look
over the neighbourhood. Rent a stapler and ask for a worksheet that will
tell you how to do it. Once you have the first two rows done it gets boring
, but think about the money you save while loosing weight . Only one
problem though, in 10 or 15 years when it starts leaking somewhere, who is
going on the roof then . Do they give a warranty?for x years?

It wouldn't hurt to read that worksheet anyway, I bet you will get it even
without renting the stapler.

Take Care

Richard

The Bald Ass Prairie Farm




"LD" wrote in message
om...
The roof of our 2000 sq. ft. bungalow (straightforward gable, 4/12
slope, no skylights) needs to be redone.

We've asked 5 contractors to give us an estimate. 4 are in the same
ballpark (i.e. $9,000 CDN), one is asking for TWICE that amount. He
says that the roof "felt soft" when he walked on it, so he's added
4700 sq.ft. worth of 1/2" plywood (to put on top of the existing one)
to his estimate. No other roofer mentioned "softness", but they did
indicate that, should they discover rotten wood underneath the
shingles, they would then charge us for the replacement (at $2.00 per
sq. ft.).

Well, I don't like surprises. Nor do I want to replace wood that
could still be in good condition.

Is there a way that I can assess the condition of the wood under the
shingles WITHOUT removing them? What signs should I be looking for in
the attic?

Also, is there a magic formula to calculate the size of a roof? None
of the roofers have quoted us the same size.

Any and all information relating to having one's roof redone is
appreciated.

(v) wrote in message ...
On 28 Jul 2004 09:58:13 -0700, someone wrote:


Also, is there a magic formula to calculate the size of a roof? None
of the roofers have quoted us the same size.

It really doesn't mater so long as the quote is a price for the entire
roof (unless somebody was so far off that they could plausibly come
back and say uhhhh....).


Errm... a contract is a contract. If the contractor screwed up it's
just too bad for him. I know of none that would not do their own
measurements. Yeah ,they could come back and beg to be let off but it
wouldn't happen in my world.

Its by the s.f. but difficulty and waste is effected by shape,
valleys, hips, dormers, etc.

-v.

Harry K