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Mobile ViewEXTERIORS of buildings ADHESIVES, EXTERIOR CONSTRUCTION AGE of a BUILDING - how to determine ALGAE, FUNGUS, LICHENS, MOSS ANIMAL ENTRY POINTS in buildings ANIMAL ODORS IN buildings ARCHITECTURE & BUILDING COMPONENT ID ASBESTOS IDENTIFICATION IN buildings ASBESTOS ROOFING / SIDING DUST ATTIC CONDENSATION CAUSE & CURE BARK SIDE DOWN on DECKS, TRIM, STEPS BASEMENT WATERPROOFING BEST CONSTRUCTION PRACTICES GUIDE BRICK VENEER WALL Loose, Bulged BRICK WALL DRAINAGE WEEP HOLES BOOKSTORE - EXTERIORS BUILDING SAFETY HAZARDS GUIDE BUILDING SETTLEMENT CAULK GUN TYPES, CHOICES CAULKS & SEALANTS, EXTERIOR CHIMNEY INSPECTION DIAGNOSIS REPAIR CATCH BASINS DECK & PORCH CONSTRUCTION DECK COLLAPSE Case Study DECK FINISHES COATINGS PRESERVATIVES DECK FLASHING LEAKS, ROT Case Study DEFINITIONS of ENGINEERED WOOD OSB LVL etc DRYWELLS, FRENCH DRAINS for FLAT SITES EARTHQUAKE DAMAGED FOUNDATIONS ENERGY SAVINGS in buildings ENVIRONMENTAL HAZARDS - INSPECT, TEST, REMEDY EXTERIOR WALL SIDING TRIM & FINISHES FLASHING MEMBRANES PEEL & STICK FLASHING for METAL ROOFS FLASHING ROOF WALL DETAILS FLASHING ROOF-WALL SNAFU FLASHING SIDING DETAILS FLASHING WALL DETAILS FLASHING WOOD ROOF DETAILS FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP FOOTING & FOUNDATION DRAINS FOUNDATION CRACKS & DAMAGE GUIDE FOUNDATION WATERPROOFING FRENCH DRAINS GALVANIC SCALE & METAL CORROSION GLUES ADHESIVES, EXTERIOR CONSTRUCTION GRADING & SITE WORK, EXTERIOR GUTTERS & DOWNSPOUTS HEAT TAPES & CABLES on Roofs for Ice Dams HOUSE PARTS, DEFINITIONS HOUSEWRAP INSTALLATION DETAILS HUMIDITY LEVEL TARGET ICE DAM PREVENTION INDOOR AIR QUALITY & HOUSE TIGHTNESS KIT HOMES, Aladdin, Sears, Wards, Others LEAD POISONING HAZARDS GUIDE LEAD TEST KIT for HOME USE LEED GREEN BUILDING CERTIFICATION LOG HOME GUIDE LIGHTNING PROTECTION METAL LATH, PLASTER & STUCCO MOISTURE CONTROL in BUILDINGS MOLD DETECTION & INSPECTION GUIDE MVOCs & MOLDY MUSTY ODORS ODORS & SMELLS DIAGNOSIS & CURE OIL TANKS PAINT & STAIN GUIDE, EXTERIOR PAINT FALURE, DIAGNOSIS, CURE, PREVENTION PAINT FAILURE DICTIONARY PAINT LAB SAMPLE PREPARATION PAINT SURFACE PREPARATION PAINTING MISTAKES PORCHES & Sunrooms PORCH CONSTRUCTION & SCREENING RAILINGS, DECK & PORCH RAILINGS, STAIRWAY RETAINING WALL DESIGNS, TYPES, DAMAGE RETAINING WALL GUARD RAILINGS ROOF ARCHITECTURAL STYLES - PHOTO GUIDE ROOF CLEANING RECOMMENDATIONS ROOF COLOR RECOMMENDATIONS ROOF DORMER TYPES - PHOTO GUIDE ROOFING DIAGNOSIS INSPECTION & REPAIR ROOF VENTILATION SPECIFICATIONS ROT, FUNGUS, TERMITES ROT, TIMBER FRAME SEARS KIT HOUSES SEPTIC & CESSPOOL SAFETY SEPTIC SYSTEM INSPECT DIAGNOSE REPAIR SHEATHING, Gypsum board SHEATHING Homasote & Other Board SHEATHING, OSB SHEATHING, Plywood SHEATHING, FOIL FACED - VENTS SIDING, Sheathing Identification - Photo Guide SIDING, ALUMINUM SIDING, ASBESTOS FIBER CEMENT SIDING ASPHALT ROOF SHINGLES on WALLS SIDING ASPHALT SHINGLE or SHEET SIDING DAMAGE by SPLASHBACK SIDING EIFS & STUCCO SIDING, FIBER CEMENT SIDING HARDBOARD SIDING STEEL SIDING VINYL SIDING, WOOD PRODUCT CHOICES SIDING, WOOD INSTALLATION SIDING WOOD, FAILURES OVER FOAM BOARD SIDING WOOD, FLASHING DETAILS SIDING WOOD SHINGLE INSTALLATION SINKHOLES, WARNING SIGNS SOLAR ENERGY SYSTEMS SOUND CONTROL in buildings STAIN & BIODETERIORATION AGENT CATALOG STAINS on buildings - QUICK GUIDE STAIN DIAGNOSIS on BUILDING EXTERIORS STAIN DIAGNOSIS on BUILDING INTERIORS STAIN DIAGNOSIS on ROOFS STAIN DIAGNOSIS on STONE STAINS on INDOOR SURFACES: PHOTO GUIDE STAIRS, RAILINGS, LANDINGS, RAMPS STONE CLEANING METHODS STONE VENEER WALLS STUCCO WAll FAILURES DUE TO WEATHER STUCCO WALL METHODS & INSTALLATION STUCCO OVER FOAM INSULATION STUCCO PAINT FAILURES SURFACE GRADING, SITE DRAINAGE TERMITES, ROT THERMAL EXPANSION of MATERIALS THERMAL MASS in buildings TREES & SHRUBS, TRIM OFF BUILDING TRIM, EXTERIOR CHOICES, INSTALLATION VAPOR BARRIERS & CONDENSATION in BUILDINGS VENTILATION in buildings VINYL Siding or PLASTIC Window ODORS in buildings VINYL CHLORIDE HEALTH INFO WATER BARRIERS, EXTERIOR BUILDING WATER ENTRY in buildings WIND ENERGY SYSTEMS WIND TURBINES & LIGHTNING WINDOWS & DOORS Best Practices, Windows & Doors CLIMATE, WINDOW CHOICES FOR CONDENSATION on WINDOWS & SKYLIGHTS DOORS, ENERGY EFFICIENCY DOORS, EXTERIOR, Selecting & Installing DOORS, EXTERIOR FRAMES DOORS, INTERIOR DOOR FLASHING DETAILS DOOR SOURCES GLASS vs HEAT MIRROR SOLAR GAIN/Loss HURRICANE, WIND, & STORM-Resistant WINDOWS LOW-E WINDOW GLAZING LOW-E VS QUAD-GLAZING LOW-E RETROFIT ADD-ON FILMS MATERIALS & CONSTRUCTION of WINDOWS POLYCARBONATE GLAZING SITE BUILT DOUBLE GLAZED WINDOWS SKYLIGHTS, GUIDE SKYLIGHT CONDENSATION PROBLEMS SKYLIGHT DESIGN ISSUES SKYLIGHT ENERGY EFFICIENCY SKYLIGHT INSTALLATION Procedures Skylight Opening Framing The Skylight Window Well Sealing the Underlayment at Skylights Ice Dam Protection for Skylights Skylight Flashing Details Skylight Installation on Low Slope Roofs Skylight Installations on Steep Slopes SKYLIGHT LEAK DIAGNOSIS & REPAIR SKYLIGHT VENTILATION DETAILS SLIDING GLIDING WINDOW DEFECTS SLOPED GLAZING DETAILS SOLAR SHADES & SUNSCREENS STORM WINDOW INTERIOR STORM WINDOW PLASTIC CHOICES STORM WINDOW WEEP HOLES SUNGAIN, FILMS, LOW-E GLASS SUNSPACE GLAZING for SUNTANNING VERTICAL GLAZING DETAILS VINYL WINDOWS VINYL / PVC WINDOW WARPING WINDOWS, ALUMINUM WINDOW CERTIFICATION WINDOW EFFICIENCY Features & Ratings WINDOWS, FIBEGLASS WINDOW FLASHING & SEALING Guide WINDOW GLAZING Based on Climate WINDOW HARDWARE PHOTOS WINDOW INSTALLATION, Flange-Type WINDOW INSTALLATION, Integral Brickmold WINDOW / DOOR ENERGY EFFICIENT, DOE WINDOW / DOOR AIR LEAK SEALING HOW TO WINDOW LEAKS INTO BASEMENT WINDOW MATERIALS & CONSTRUCTION WINDOW SHADING, SCREENING WINDOW SOURCES WINDOW TYPES, Guide WINDOW TYPES - Photo Guide Window & Door Sources WINTERIZE A BUILDING More Information |
Skylight flashing details: here we provide details about framing the skylight opening, constructing the skylight well or chute, sealing the skylight, flashing around skylights to avoid leaks, and protecting from ice dams and ice dam leaks at skylights. We also discuss how to install a skylight on low slope roofs and on very steep roofs. InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers nor with topics or services discussed at this website.© Copyright 2012 InspectAPedia.com, Daniel Friedman, Steve Bliss, Wiley & Sons, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use page top links to major topics or use links at the left of each page to navigate within topics and documents at this website. Green links show where you are in a document series or at this website. Skylight Installation Procedures
In this article series we discuss the selection and installation of windows and doors, following best construction and design practices for building lighting and ventilation, with attention to the impact on building heating and cooling costs, indoor air quality, and comfort of occupants. We review the proper installation details for windows and doors, and we compare the durability of different window and door materials and types. See WINDOWS & DOORS our home page for window and door information, and also see WINDOW TYPES - Photo Guide for a photographic guide to window and door types and architectural styles. According to Best Practices Guide to Residential Construction Chapter 3, BEST PRACTICES GUIDE: WINDOWS & DOORS: Skylight Opening FramingTake care when framing skylight openings to make the opening as accurate and square as possible. T his will simplify both the installation and trim, since most skylight designs leave little margin for error where the interior finish meets the frame. Unless using a skylight designed to fit between 16- or 24-inch on-center framing, you will need to head off the opening and use double trimmers on either side. For truss roofs, consult the truss designer or an engineer before modifying the truss plan or cutting an existing truss. In new construction, trusses are typically doubled on either side of the opening with 2x cross pieces framed in “ladder” fashion. The Skylight Window Well: the Light Well
Our photo (left) shows a wood-framed skylight well (the builder called them "shoots", meaning "chutes") in a truss-framed roof in Minnesota -DF. To frame a perfect skylight well the builder actually constructed the shell on the floor below then lifted and nailed it into place below the skylight. We took care to assure that the sides of the skylight well were insulated. With an attic, the top side of the well is typically framed perpendicular to the roof plane and the bottom and sides are framed plumb. For small skylight wells, the opening can be created with 3/4-inch plywood while larger openings are typically built like stud walls. Make sure the well is sealed tightly against air infiltration and well-insulated to guard against condensation on the skylight or sides of the well. It is also possible to splay the two sides of a skylight well in addition to the top and bottom sides, although the framing and drywall are a lot more complicated. To keep the four sides of the skylight window well flat, the bottom of the opening must be shaped like a trapezoid, wider on the high side of the opening. You can just see that feature in our skylight photo above. To keep the opening rectangular at the ceiling plane, the two sides become curved like twisted strips of plastic. This requires framing with angled struts and bending the drywall. Either approach makes for a complicated framing job. Also see Skylight Light Tubes. Sealing the Underlayment at Skylights
Detail corners carefully using patches of moldable flashing (see FLASHING MEMBRANES PEEL & STICK) if necessary. Tuck the top piece of membrane under the roofing felt above, and lap the lower piece over the roofing felt below. With ganged window units, use a single strip of membrane between each unit, running down one skylight frame, across the mullion, and up the next skylight frame. Ice Dam Protection for Skylights
Skylight Flashing Details
Most major skylight manufacturers provide flashing kits for asphalt shingles as well as specialty flashings for tile and metal roofing, typically with a wraparound head flashing and moldable apron flashing that conforms to the roofing profile. With asphalt shingles, avoid skylights that provide only a continuous side flashing, which relies on roofing cement for a waterproof seal. Step flashing is much more reliable. With metal roofing, use the manufacturer supplied kit or have the roofing contractor fabricate a matching flashing from the metal roofing material. While a custom flashing can create a more attractive installation, make sure the corners of the head flashing are properly sealed with solder or a high-performance caulk. Also see Skylight Installation on Low Slope Roofs
The raised skylight curb should be sealed on all sides with peel-and-stick membrane carefully sealed at all corners, as in Figure 3-21.
Skylight Installations on Steep SlopesFor very steep slopes, such as mansards, skylight manufactures typically recommend a water deflector or Z-flashing to safely divert water around the unit. Check with the manufacturer for steep-slope requirements. Skylight Manufacturers & Product SourcesAndersen Windows and Doors www.andersenwindows.com Skylights and roof windows with exterior sash clad with glass-fiber-reinforced material Milgard Windows and Doors www.milgard.com Skylights with aluminum frames (thermal break optional) with vinyl subframes on operable models; optional motorized controls with rain sensor Pella Windows and Doors www.pella.com Wood interior, aluminum exterior, optional motorized controls, and manual or motorized fabric-pleated shades Roto Frank of America www.roofwindows.com Wood interior, aluminum exterior, optional motorized controls, and manual or motorized fabric-pleated shades; Sweet16 model fits 16 in. o.c. framing Velux America Inc. www.velux.com Skylights and roof windows with wood interior and aluminum-clad exterior. Options include insect screens, blinds, motorized controls and shades with rain sensor, electrochromatic glass, and flashing kits for metal and tile roofs and mulled units Skylight Light Tube Manufacturers & Sources SolaTube www.solatube.com Light tubes from 10 to 21 in. in diameter; options include electrical lighting, daylight dimmer, and integral bath fan Sun-Tek Skylights www.sun-tek.com Light tubes from 10 to 21 in. in diameter; options include electrical lighting and multitube Spyder skylight Velux America Inc. www.velux.com Sun Tunnel light tubes from 14 to 22 in. in diameter with flexible or rigid tubes Industry Associations for Windows & DoorsAmerican Architectural Manufacturers Association (AAMA) www.aamanet.org Efficient Windows Collaborative www.efficientwindows.org National Fenestration Rating Council (NFRC) www.nfrc.org Sustainable by Design www.susdesign.com Shareware calculators for sun angles, solar heat gain, and shading Window and Door Manufacturers Association (WDMA) www.wdma.com -- Adapted and paraphrased, edited, and supplemented, with permission from Best Practices Guide to Residential Construction. Questions & Answers regarding this article. Ask a Question or Search InspectAPediaHTML Comment Box is loading comments...
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