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TOPIC: Condensation Issues

CONDENSATION

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I HAVE A METAL ROOF WITH A TERRIBLE CONDENSATION PROBLEM. THE ROOF IS MADE OF METAL Q-DECK WITH 3.5 INCHES OF CONCRETE ABOVE AND THEN THE ROOFING MATERIAL.WHEN I SAW THE CEILING LEAKING I REMOVED ALL SHEETROCK AND SOAKING WET INSULATION. UNCOVERED I SAW THE WHOLE CEILING SWEATING. I ALSO DISCOVERED THE PLUMBING WASTE VENT , VENTED INTO THE ATTIC SPACE. NO ROOF VENTS. WHAT DO YOU THINK?
Guest User

12/16/2005
That plumbing stack, as well as any other exhaust stacks, needs to go to the outside. There may be roof leaks at hand, too, so I would have an expert look at the roof. Aside from that, you need ventilation, preferably soffit intake vents and a ridge vent as exhaust. Todd Miller
Todd Miller
Isaiah Industries, Inc.

12/16/2005
THIS WEEKEND I CORE DRILLED AND INSTALLED 6, 6" ROOF VENTS WITH CAPS AND STRIPPED THE ENTIRE CEILING OF SHEET ROCK AND INSULATION TO EXPOSE THE Q-DECK SO THAT IT WOULD DRY.APPX 1000 SQ FT. THIS WEEK I WILL VENT THE PLUMBING STACK AS WELL AS BATHROOM VENTS OUTSIDE.FYI THIS IS A 3 STORY MIXED-USE BUILDING. ALL PROBLEMS ARE ON THE 3RD FLOOR. AFTER THIS WHAT'S MY NEXT STEP? INSUALTE AND ROCK? WHAT ABOUT A DROP CEILING?
Guest User

12/19/2005
I am not sure I understand your ventilation. The goal of ventilation is to continually "bathe" the underside of the roofing with outside air. This is best done with soffit vents as intake and ridge vent in the roofing system as exhaust. Does this coincide with what you have done? Todd Miller
Todd Miller
Isaiah Industries, Inc.

12/19/2005
I AM NOT SURE. WE PUT STACK VENTS THROUGH THE ROOF FOR VENTALATION. DO YOU THINK IT WILL HELP?
Guest User

12/20/2005
I am not sure of the slope and what is on for a roof covering but when you have a concrete deck, the insulation should go on the top side to provide a thermal break as it will transmit the cold in and cause conensation on the interior side which happens to be the Q deck. Was there an attic space between the ceiling and decking and at what point was the insulation and drywall?
Allan Reid
Dura-Loc Roofing Systems, Inc.

12/20/2005
yes, there is attic space. sheet rock ceiling, insulation r-9 above, then 3-4 inches of attic space, q-deck roof with 3.5 inches of concrete, NO ISULATION ABOVE CONCRETE , just 1.5 inches of roofing material.remember the open plumbing stack burried in wall and vented directly into attic, has been capped since . i will bring stack through roof soon.at this point the sheet rock and insulation have been removed. the under side of the q-deck is exposed and has completely dried.the apartment is vacant, the heat is on [50 deg f ]. help, please.
Guest User

12/20/2005
Assuming the roof does not leak, then I would recommend insulating the underside of the deck with sprayed in place insulation, the installing a new ceiling. The insulation will act as a moisture barrier and stop the condensation and there would be no need for the roof vents. You could then install a drop ceiling to fireproof and finish it off. Install the hangers into the deck before you have it sprayed.
Allan Reid
Dura-Loc Roofing Systems, Inc.

12/21/2005
THIS SOUNDS LIKE THE SOLUTION. I DO NOT BELIEVE THE ROOF IS LEAKING. I HAVE ALREADY INSTALLED ROOF STACK VENTS, CAN I LEAVE THEM IN PLACE. CAN YOU RECOMMEND A COMPANY TO DO THE JOB OF SPRAYING THE INSULATION? I'M IN NEW YORK [QUEENS COUNTY] CLOSE TO SHEA STADIUM. THANK YOU THANK YOU
Guest User

12/21/2005
Sorry you are on your own here. Try the yellow pages and internet, there are usually many around.
Allan Reid
Dura-Loc Roofing Systems, Inc.

12/22/2005