Replies

1. 
   Piffin | Apr 21, 2003 04:32am | #1

   venting - it looks to me like you have some sort of ridge vent already in the wood above. If the sheathing is preventing air from flowing through to it, cut some holes.

   The leak - Lots of places that water could be getting in at that sort of location and details.

   Could be splash up onto corner from the fall line off the copper onto the lower roof

   Could be getting in at base of valley in copper

   I don't see a standing seam under the return so the roofing detail is modified there - maybe a flaw.

   Could be it lacks a kicker to return water from under the frieze out of the wall before it hits the cornerboard

   Most likely guess from here is that splashed water is entering the cornerboard and getting behind the base flashing for the lower roof. Remove the cornerboard and put felt or ice/watershield over the lower base flashing and under the upper frieze flashing. Then replace the cornerboard.

   .

   Excellence is its own reward!

   
1. 
   dmeenan | Apr 21, 2003 06:58am | #3

   thanks Piffin....

   what's a kicker -- because that does seem like it would help here to get water away from that spot (under the frieze) in the corner ?

   thanks

   Devin

1. 
   Piffin | Apr 22, 2003 03:42am | #5

   You know what a base flashing is I presume. The first piece of step flashing that goes down is ofeten allowed to lead water in behind the siding because it terminates there.

   It should always have a bend in it to divert (or kick - thus the kicker) water out to the top or face of the siding - in your case, the cornerboard.

   Wish I had a drawing on this - I know somebody posted a good one here once. Maybe from the Building Science website..

   Excellence is its own reward!

2. 
   Ethos | Apr 21, 2003 06:07am | #2

   Hi-

   I don't recall reading what the present roof insulation consists of.  But, what I'd be focusing on is getting much more of it installed.  To mitigate the ice dams and to make the winters more comfortable and less expensive.

   A good approach that we have had success with is to glue and screw 4 or more inches of rigid isocyanurate insulation through the existing ceiling and into the joists using long screws and fender washers.  A second layer of lightweight drywall can in turn be glued and screwed to and through the rigid insulation.  Since it is, in effect, laminated to the underlying layers it can be 1/4" thick and will not sag.  This, in turn, reduces the dead load on the joists and should make this approach tenable.  Four inches of rigid can add up to R-28 or so, 6" R-40.  It's the insulation that is going to fix your problem, so focus on it.  Once you've gotten your roof up to R-40, then install vents.  If you install additional vents and don't deal effectively with the insulation, you'll move out because it'll cost a thousand a month to attempt to heat a cold house.

   Remember, the reason vents will help with the ice damming is because they'll lower the temp. of the attic and in turn keep the snow frozen.  Adding lots of insulation will do the same thing.  It'll do it by keeping the heat inside the conditioned envelope of the house.  The vents however,  will do it by exhausting the attic air more rapidly than at present.  This, without additional insulation will be like leaving a window cracked all winter.

   BTW, who designed your project?

   Lance

1. 
   dmeenan | Apr 21, 2003 07:20am | #4

   Hi Lance,

   I will double check the insulation in terms of R value. For the second floor there is insulation in between the second floor joists (or laid on top of them) -- there isn't any in between the rafters -- that would seem to be ok -- don't have need to ever heat the attic --- given that this is an old house it's a variety but for the most part I have 2 x 10's as joists and the insulation sits within (or above) the joists -- it'll be a ryhmes with itch to re-do with bat type insulation -- main problem is that only the main box is accessible -- there's one other hatch but given I had low plates upstairs in some of it to match the existing and the ceilings are a foot or more above the plates there's not a heck of alot of attic space so we didn't provision for access -- there's one hatch on one end and the access to the other (from the main box attic) is filled with hvac -- if I have to I can open up from the main box to provide some access but it ain't going to be alot and it'll be a pain in the...not opposed to the work just not sure how viable it would be to expect anyone to get up there to work.

   If I understand what you suggest I'd be losing 4 inches of headroom on the second floor -- I can't afford the headroom and I'd have to re-trim all my openings and doors -- it's an old/new house and I don't have the room -- I'm thinking open up the space into the area under the copper roof and look into what Piffin suggested which is some type of blown insulation but I want to keep an open mind in that is how I will learn and will eventually come up with the best solution.

   Project was designed by a local architect (I live in Ridgefield, CT) -- he drew the addition -- wasn't originally planning on whole house remodel but one thing led to another --- we've been figuring out the details as we go -- not the best approach in hindsight but had I been thinking clearly from the start I wouldn't have tackled something this big.

   Thanks again - btw not to be greedy but I posted a reply to your thoughts on how to handle this with the folks doing the repairs -- was wondering if you had a chance to read it as I would be interested in your take.

   Devin

3. 
   geob21 | Apr 22, 2003 04:14am | #6

   It looks like you have about 500 square feet of roof draining to about 6 lin feet of soffit. With a header above that window there can be little space for adequate insulation and venting. What is the distance between the top of those windows and the interior ceiling?

   _______________________________________

   If you were arrested for being a quality builder would there be enough evidence to convict you?
1. 
   dmeenan | Apr 23, 2003 04:16am | #7

   There's about 8 3/4" inches from the top of the window to the ceiling -- that's 4 1/4 for casing and 4 inches about that...

   I've been thinking about your observation -- 500 feet into six feet of soffit -- realizing that for all intents and purposes I have a funnel -- so I'm starting to wonder and would love feedback -- let's say that part of the problem is the insulation/venting -- checked the insulation in the lower roof -- that's r38 so that's pretty good -- I realize I could have gaps in the upper attic but for sake of argument let's say its ok and I cut into the old house sheathing to get airflow from the copper roof up to the ridge on the main box -- I can't help but wondering if I have a fundamental problem -- which is the upper part of the copper gets more sun -- it more open then the lower part which is tight between the two gables -- there's also more snow up there -- so that heats up, let's say even a little faster than the lower part -- only cause of the sun -- now I have a much greater volume of snow on top that's melting faster than the bottom -- again assume I have fixed the insulation/venting -- well how is not going to back up or is the argument against my thinking (wont' go so far as to call it logic :-)) that the sun will not warm parts of the roof differently....

   so anyway that's what I've been thinking -- I will cut into the exterior sheathing to get better airflow -- but I will have to do something on the lower part of the copper based on roof size,location and dimension (looks like a flat funnel) because I'm starting to think that even if we get that roof at an even tempurate from the internals we cannot control the exterior and the upper roof will always get more sun --- does my thinking make any sense ?

   That's why I'm starting to wonder if I don't have to put those electric coils on the roof -- not sure how they work over copper but I have to keep that lower part melting as quickly as the upper ?

   Piffin if you happen to read this wouldn't mind your perspective given your local climate...

   as always thanks for all the help and insight - you guys rock.

   Devin

1. 
   geob21 | Apr 23, 2003 04:35am | #8

   My personal opinion is no matter what you do when there is snow on the roof your heat loss through that header, door and window will always cause an ice dam. Making shoveling or heat coils your only remedy.

   _____________________________________________________If you were arrested for being a quality builder would there be enough evidence to convict you?

1. 
   dmeenan | Apr 23, 2003 04:57am | #9

   hi,

   unfortunately I have to ask about which roof leak you are referring to  (or both) -- the one with the french door or the one with the copper roof and the awning windows ?

   thanks

   ps was trying to think through the framing on the exterior wall with the french doors -- I know they notched the rafters so I'm thinking it's possible that there's an 8 inch header but the rafters are notched and sit below the header which is reducing the headroom -- make sense ?

   thanks

1. 
   geob21 | Apr 23, 2003 05:18am | #10

   It makes sense but I think in both situations you don't have enough room for adequate insulation and ventilation space above the header. You need a minimum of 12" between the header and the roof sheathing. Add to that the heat loss through the window or door thats translating directly up into the soffit vent your fighting an uphill battle.

   Mother nature can be a cruel b!tch on poor design and I think your options are limited to bigger powers( the electric co.) to beat her in this situation.

   ________________________________________________If you were arrested for being a quality builder would there be enough evidence to convict you?