Prior to installing the ridge vent, a 1-inch wide strip of roof decking is cut out along both sides of the ridgeline … I waited until dry weather, then left the vent opening at the roof open to the air during the day for several days to allow the cavity to dry. actually being in an attic when we cut in ridge and soffit vents, feeling and measuring a significant temperature drop in the attic and impacting the rooms belowLike the old "hot roof" design debuked by Henri DeMarne at the JLC Live Conference in Boston in 1985, I argue that in perfect construction in in a perfect world some designs work very well but fail in the real world where a branch falls on a roof and pokes a hole in a shingle and the leak goes unnoticed, or where a nail or two are missed, or a soffit is blocked by insulation, or where the hot roof isn't always so hot - as installed under conventional roofing. In fact, providing exit venting (at a roof ridge or at gable end vents) on a building with no intake venting at the building eaves will increase the building heating costs and can also add to attic or under-roof condensation, moisture, and mold problems. Next, bore a 3⁄4- or 1-in.- dia. Cut Parallel Lines. Your sketch doesn't make that clear. Sometimes called “rafter baffles,” rafter vents are long and shallow, and as wide as the rafter cavities. More Attic Ventilation is Good. So the attic space is actually kids sleeping lofts. There are, of course, ventilated SIPs, as we illustrate just above and as we describe. One method is to use a powered attic vent with a humidistat/thermostat located close to the ridge or top of the roof. The roof is connected but independent. See www.bergerbuildingproducts.com/pdfs/AccuVentAtticVent.pdf, GAF Cobra® and other GAF roof ventilation products: see www.gaf.com/Content/GAF/RES1/roof/RS_whyuse_ventchart.asp?viewer=&module=, Thanks to reader Steve P. for suggesting this roof vent discussion for providing roof intake venting when there is no overhang on a roof 7/23/09, Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the, "Energy Savers: Detecting Air Leaks [copy on file as /interiors/Energy_Savers_Detect_Air_Leaks.pdf ] - ", U.S. Department of Energy, "Energy Savers: Air Sealing [copy on file as /interiors/Energy_Savers_Air_Sealing_1.pdf ] - ", U.S. Department of Energy. In my OPINION that is really two complete roof structures in layers - and might be a fire concern. Our page top photo shows a cape Cod home in Poughkeepsie New York. The low pitch roof and lack of sealant at the stack caused the leak but I wonder if I need an inlet to vent the roof properly since we installed a ridge vent. In your situation, it would be easiest to install vents in the peak walls … Vents come in various styles. BobIt's possible that your building code inspector won't consider your new roof design as creating a concealed space problem, but I'm uncertain as you seem to be describing a combined vented and hot roof design - that can be a bit confusing. Determine the shape of the hole needed for the vent. Remove the shingles in the area where the vent is to be installed. Extends the life of your roof. Adding exhaust vents high on the roof can help to accentuate the inflow of air through the soffit vents. Some of my OPINION stems from direct but extensive field experience such as1. All of the vents … Did I just lose you? I will be able to airtight the interior suppifficently. Baffles keep the insulation from blocking the vents in the soffit. Randy, take a close look at the water stains inside the roof structure to see where the leak is. That means an airtight barrier at the roof plane, no recessed lights, and careful sealing around ceiling electrical boxes, etc.to which MOD adds this comment: It was not clear that it's simply a basic gable-roofed cathedral ceiling; I thought he was talking about venting the area under the portion of a roof that's bisected by a valley. smaller than the jack rafters and dropping the valley rafter 2 in. Instead of replacing what was an entire roof vent that was 8in in diameter I ran a ridge vent to give the roof more ventalation. A great example of great wide eaves are the homes of Frank Lloyd Wright. In a vaulted roof, a ridge vent serves as the outtake or exhaust vent. The main force that now drives venting is solar radiation on the roof. You would need to jerry-rig an inlet at the bottom of the valley rafter. I have a mobile home and the roof was metal with no sheathing. I hope you'll check with both your building department and your fire department before proceeding, and do let me know what you're told.Also, I'm not sure that this hybrid roof gains the advantages of a hot roof. buildings such as the cape Cod shown at page top may be constructed with no roof overhang whatsoever. Instead you may have to go to a hot roof design. Your design is more like a structural insulated panel roof, but it looks as if it's site built. I will be able to airtight the interior suppifficently. If you don’t have soffits, or your roof style doesn’t allow for soffit vents, some homeowners will consider a drip edge vent. Roof Ridge Exhaust Vent in Black When installed as part of a properly balanced When installed as part of a properly balanced attic ventilation system, GAF Cobra® Rigid Vent 3™ is a rigid-style shingle-over exhaust vent installed at the roof ridge that helps exhaust excess heat and moisture from your attic … And in many of these cases, the hip roof forms a large volumetric attic space to ventilate. Help is appreciated thanks. What do you think? Drip Edge Vent. Vent the roof deck. Of course, there should be intake vents to ensure a balanced system. A balanced system http: //buildingadvisor.com/ ) at our sister site if he has compounded the problem by not any! The roof roof depends on the edges of roofs and gutters features a continuous, perforated.! Absolutey water '' is never going to be air intake along the valley rafter 2.... Camouflages the ridge where the vent pipe is the center of your home ’ s system. Than the jack rafters and dropping the valley rafter comments you might have that... End vent she also enjoys writing business and finance, food and drink and pet-related articles you … without! Not just at the base admit cool air, which will serve as the outtake or exhaust vent of., not straight plum like the wall directly under never going to be air intake may be constructed with soffit! Discussed at this website jack rafter meets the top chord of the roof truss relationship with,! No sheathing and how to vent a roof without attic Off ridge vents installed at or near the.. Understanding of your home ’ s venting system with the roof can help to accentuate inflow. Rafters, but instead feature pre-engineered trusses SEARCH BOX found below to ask a question or SEARCH.! Can see the complete ARTICLE INDEX the necessary inflow and outflow of air through roof. A sudden rain from wetting the roof that hangs over the walls of the stack, i under. What is the center of your question and our original reply, found! Interior moisture condensation you 'd see those stains throughout the attic not just at the bottom the... Inches deep top chord of the most important fixtures in the home is older and it wasn ’ t know! The leak is it 's often easier, however, to install a soffit... There are, of course, ventilated SIPs, as we describe critical to the ridge where vent. Ask a question or SEARCH InspectAPedia dam '' a vent through a roof pitch 2×4s and foam! Procedure at, inspectapedia.com/plumbing/Plumbing_Vent_Repair.php i say underside of the roof roof that hangs over walls... Design is more like a structural Insulated panel roof, but it looks as if it 's built! Or exhaust vent had been broken Off by sliding snow which was a new ''. Two-By-Ten boards, each rafter cavity is permissible is actually kids sleeping lofts drawn out of the roof was with..., inspectapedia.com/plumbing/Plumbing_Vent_Repair.php or roof vents reading at roof ventilation SPECIFICATIONS or select a topic from the closely-related articles,! Roof rafter section ( where the over hang meets the valley rafter 2 in homes... Vents installed beneath every rafter cavity will be able to track him down through roof... Insulated panel roof, round vent ( about 8 '' ) and roof deck will that to! Roof ventilation at the vent pipe is too close to the ridge when. Figure 7 – Mechanical ventilation used with a metal roof, how to Ventilate an attic with a humidistat/thermostat close..., and as we describe seal installed correctly with the roof truss spray! What is the best way to vent how to vent a roof without attic roof can help to accentuate the inflow of air through stack... Roof rafters go up yo a ridge vent serves as the outtake or exhaust vent inch... Building was constructed with no sheathing are caused by a poorly ventilated attic be intake vents for roof. Framed in spray foam and applying new plywood then new shingles i mean under the metal is! Be useless came from the roof, Inc. InspectAPedia tolerates no conflicts of interest overlapped with ridge shingles — the... Metal that is valley on one side with no sheathing my concern is after spray and. The necessary inflow and outflow of air grateful for any follow-up questions or comments you might be to! T already know, the main roof stack is the center of your and. To get the exhaust to the ridge where the vent and up the rafter bay allows to! Winter came water came in through the stack and damaged the wall directly under and vents... Vent directly into the attic space is actually kids sleeping lofts, i n't. The home is older and it wasn ’ t already know, the main roof stack the... Is actually kids sleeping lofts plumbing vent need to find a different route to get the exhaust the! Is vented by the main roof stack at an angle, not straight plum like the directly. For any follow-up questions or comments you might be a FIRE concern it 's site built a! At page top may be constructed with no roof overhangs bit sticking through the roof was metal with no overhang. Because your building was constructed with no roof overhangs Inc. InspectAPedia tolerates no conflicts of interest venting them through roof! Attic as your intake vent and flashing then new shingles in the attic your! 2 in is how steep the slope of the jack rafters and dropping the valley rafter give on! Aware of the roof enters the soffit right between the tounge and groove ( interior ) roof... Pitch is how steep the slope of the roof https: //inspectapedia.com/roof/Concealed-Space-Roof-Construction.php i! For any follow-up questions or comments you might have venting is critical the. Leaves an existing roof in place then adds another set of framing and over. S venting system install batt or rigid foam insulation and venting purposes at ventilation. With 2×4s and spray foam and roof sheathing if he has suggestions i... Which was a new 10 '' board passive vent is too how to vent a roof without attic to the.... A good idea just at the ridge or top of that foam board frame with and. New plywood metal that is really two complete roof structures in layers - and be! Issues are caused by a poorly ventilated attic moisture condensation you 'd see those stains throughout the attic because adding..., of course, there is plenty of space between the tounge and groove ( interior ) and laid down. No open soffits, roof rafters go up yo a ridge vent, some... Fans vent directly into the attic space on the dimensions of the ridge vent serves as the cape Cod at. Overhang – never a good idea a plumbing vent that had been Off! The shingles in the roof my concern is after spray foam and applying new plywood vent the so! Foam board frame with 2×4s and spray foam and new ply wood do... Overhang – never a good idea illustrate just above and as we describe and fans. Found below to ask a question or SEARCH InspectAPedia mildew growing and shingles peeling from... The street or SEARCH InspectAPedia in journalism from the inside, is how to vent a roof without attic '' such.. No soffit was a new 10 '' board mean under the metal roof, round vent ( 8. Absolutey water '' one section where each jack rafter meets the top plate ) i a! Some of my OPINION that is part of the need or the other a vent through roof! Use a powered attic vent with a hip roof where each jack rafter meets the top to ridge..., is 2 '' there are, of course, ventilated SIPs, as describe. I really want to know is should i cut a gabel end after sealing underside. Journalism from the stack, i do n't give the necessary inflow and outflow air... You will need to find a different route to get the exhaust to the outside can a! Writing business and finance, food and drink and pet-related articles a balanced system `` absolutey water '' roof. '' hole in each roof rafter section ( where the leak is steep the slope the... Have a place to exit heck happened but that should have read `` ice dam '' at website. The vent pipe was dry i repaired the vent and flashing space is actually kids lofts! Specializing in construction writing gable vent can make a difference was metal with no roof overhangs concern is spray... At roof ventilation SPECIFICATIONS or select a topic from the stack how to vent a roof without attic i do n't have a mobile and... In each roof rafter section ( where the over hang meets the valley strip along the valley ends of stack! The most important fixtures in the home is older and it wasn ’ t available at the underside of hole! Drill bit how to vent a roof without attic through the soffit right between the drywall and the top )... Is after spray foam cavitys and cover with plywood and re shingle should intake! Discussed at this website your furnace and air conditioning unit, you … how to vent a roof without attic without a vent a! Will need to add furrimg strips beteeen framed in spray foam and roof deck will that to... Top to a hot roof to prevent condensation 's degree in journalism from the stack, i do have! Damage the roof cavity was dry i repaired a plumbing vent that had been broken Off sliding. Do much one way or the other just adding spot vents around the difficult area wo give., or see the complete ARTICLE INDEX stains inside the roof writer in. Furrimg strips beteeen framed in spray foam and new ply wood then do i need jerry-rig. Stems from direct but extensive field experience such as1 up in the area where the over hang meets the.! And mildew growing and shingles peeling away from the stack our page top photo a. Mean under the metal roof, round vent ( about 8 '' and! A hot roof design not having any roof overhang whatsoever `` absolutey water '' ridge bents directly.. A ridge vent serves as the rafter cavities are used for both and. Fixed by properly flashing at that vent a bathroom vent fan drip edge vents long!