OSB roof panels should always be installed with the grade stamp facing into the attic and the screened surface (with the nail guide lines) facing up. They can range from the standard 4’ x 8’ piece to a 4’ x 9’ or even a 4’ x 10’ . 4. Corrugated roofing is a great way to top a garden shed, shop, or patio. On panels with a screened surface or skid-resistant coating, install panels with the non-skid surface up. Each day, Pro Builder's editors assemble the latest breaking industry news, hottest trends, and most relevant research, delivered to your inbox. Norbord applies the latest in strand & resin technology, combined with continuous press mill capabilities to customize lengths, widths, thickness and surface characteristics. For example, if your roof is 1,500 ft 2 then it will take 47 sheets of plywood to sheath it. Sheathing a large expanse like this is relatively straightforward, though job efficiency decreases as the height increases. Position the first piece of plywood or oriented-strand-board sheathing on the bottom edge of the rafter tails at one end of the roof. The Ten most Important Fasteners for Installing Roof Sheathing, West Fraser Completes Acquisition of Norbord. The strength axis is usually the long direction of the panel but the grade stamp will indicate it. OSB is currently selling for less than plywood by approximately $3 per sheet, meaning a savings of several hundred dollars per conventional home. Position panel. How to install osb roof deck sheathing. While its allowed by code, we strongly advise against using OSB for sheathing. A minimum net free ventilation area of 960 square inches for each 1,000 square feet (1/150th) of the ceiling area is required. Fasteners should be driven flush with the panel surface. Plywood is a bit more expensive, but is usually stronger and is often selected in cases where the roof covering is heavier, such as for slate, clay, or concrete tile roofs. Both OSB and plywood absolutely hate water, Lipinskiy mentions, going on to say that the most important part, regardless of which decking option you choose, is that all penetration points on a roof are sealed. / Posted in: The Ol' Sage Builder. Boards used for sheathing range from those with a 4-inch face to 48-inch-long plywood sheets. Because of its construction, some manufacturers actually make larger sheets of OSB. 7. Do not vent exhaust air directly into roof cavity or attic. Telko makes nine different OSB products of which two are for sub-flooring. Fasten panels with a minimum of 8d Common (0.131-inch by 2-1/2-inch) nails spaced a maximum of 6 inches on center at supported panel ends and edges. For pitched roofs, wear skid-resistant shoes. 6. Here are some things to consider when choosing your decking material to install on a roof. This will allow the silicone to squeeze out … H-clips provide additional stiffness between bearing points for the unsupported edges of wood panel (plywood or OSB) roof sheathing, along with the necessary 1/8” gap for expansion, as shown below illustrated on a bag of Simpson H-clips. How it’s made—Plywood vs. OSB. Also make sure that you get your supporting timbers at the correct spacing. 1 Tags: Best of the Blog, Roof Sheathing, Solarbord, Trubord. By creating an account, you agree to Pro Builder's terms of service and privacy policy. OSB comes in 4-by-8-foot sheets, as does plywood, but the manufacturing process allows the production of longer and wider ones. Once you have aligned it, measure and trim to the correct size with a sharp knife. OSB sold in the UK is made to comply with BS EN 300 Oriented Strand Board (OSB) Definitions, Classifications and Specifications. The same goes for wall sheathing and flooring panels; always install with the grade stamp up so that inspectors can do their jobs easily. OSB sheathing is a special type of board that is well-engineered being composed of strands of compressed wood which are layered and unionized together using a resin. It is generally believed that OSB is cheaper than plywood. This can be done with a straight piece of lumber (6 feet to 10 feet long) or a long carpenter’s level. A structure's roof truss spacing can vary from every 12 to 24 inches. Net free ventilation area may be reduced to a minimum of 480 square inches for each 1,000 square feet (1/300th) when certain building code provisions are met (see Section R806.2 of the 2012 International Residential Code or Section 1203.2 of the 2012 International Building Code for more details). Lorem ipsum dolor sit amet lorem ipsum dolor sit amet lorem ipsum dolor sit amet. If you get 45 or more pounds of pull out resistance, that’s considered acceptable for most applications. Roof sheathing (or decking) is one of those elements. Check building code requirements for installation of panel edge clips. When the grade stamp is covered by roofing, the building inspector will not be able to confirm that the correct OSB roofing panel was used. Talking about plywood or OSB for roofing, you cannot miss the information of the cost. Some people falsely conflate OSB with particle board. OSB roof panels should always be installed with the grade stamp facing into the attic and the screened surface (with the nail guide lines) facing up. With all the available technology out there for builders, why isn’t it easier and faster to build?…, Online sales growth for the past five years signals buyer preferences were already changing, but…, © COPYRIGHT 2021 PROFESSIONAL BUILDER. What H-Clips Do. OSB is lightweight, relatively inexpensive, and strong enough to resist bending or breaking should someone walk on the roof. Each day, our editors assemble the latest breaking industry Subscribe for unlimited access. You only need some basic tools and materials. Roof trusses must be dry when sheathing a roof with OSB, to prevent mold growth in the roof, and coverage gaps as the trusses dry and shrink. Edge clip requirements depend on the relationship of the panel Span Rating to the actual distance between roof framing. Which way should my OSB roof board’s be installed? Plywood is a bit more expensive, but is usually stronger and is often selected in cases where the roof covering is heavier, such as for slate, clay, or concrete tile roofs. And of course make sure he locates the leak source and fixes that too - might be on that sheet or might be adjacent or uphill, or commonly at a penetration through it or an unhill sheet. I used 7/16” OSB, a wall sheathing I’ve been very happy with in the past. You should be prepared to have about 15 percent waste, so multiply your figure by 1.15. At intermediate supports, fasten panels 12 inches on center. West Fraser is a diversified wood products company with more than 60 facilities in Canada, the United States, the United Kingdom, and Europe. January 19, 2018 Nail a 2x4 onto the lower part of the roof, to use as a footstop. Sagging may result if panels are installed incorrectly. Typically 3/4"(18mm) for floors and 3/8" (9mm) for walls and 1/2" (11mm) roof. Use a chalk line or straight edge to align fasteners on framing. However, you might find that OSB can better suit your needs than plywood for the roof. This will mask surface imperfections and reduce the risk of shingle ridging. Your privacy is important to us; your email will remain confidential and will not be shared with any other parties. 3. Many times leak through the roofing will run downhill on the water barrier till it finds an opening in it (commonly at a roof penetration) then come through and rot the sheathing at that point. Install intermediate fasteners, starting at panel edge. Install baffles providing a minimum of 1 inch of clear space between framing and/or under roof decking at eaves to ensure that ceiling or roof insulation does not block ventilation paths. You’ve read 2 premium stories this month. The square footage of a Hip roof area is identical to the square footage of a Gable roof of the same measurements. Use shingle underlayment felt conforming to ASTM D226 Type I, ASTM D4869 Type I, or ASTM D6757 (self-adhering polymer modified bitumen sheet underlayment should conform to ASTM D1970) or check roofing manufacturer's recommendations if delays are anticipated during construction. You've decided it's time to replace your roof. Installation instructions. This will provide time for roof sheathing to adjust to humidity and moisture conditions. Sign up today! Stand on the panel over the framing near the fastener location to ensure contact with framing while driving fasteners. Get Pro Builder in your inbox. For shed construction there are two commonly used grades of OSB… Avoid Nailing or Stapling Edges of OSB Panels The first raw of fixings at eave is located at 2,5 cm from the edge of the roof support (OSB or purlin). Get all the latest news and industry tips straight from Norbord delivered to your email. (and scroll down to see more details on each, with installation hints and tips, below), Step 1: Check the nailing surface is level, Step 2: Ventilate the roof according to current building codes, Step 3: Properly fasten panels (including fastening and spacing hints), Step 4: Cover sheathing with shingle underlayment felt, Step 5: Install shingles according to manufacturer recommendations. So, dividing the area of the roof by 32 will give you the number of sheets needed. For example, perhaps the majority of the roof is already sheathed and you simply need to get the last two pieces up that were not in your original material calculations. Because of this manufacturing process, OSB is at least half the cost of CDX plywood. Unless otherwise recommended by the sheathing manufacturer, cover the sheathing with shingle underlayment felt to minimize exposure to weather. But OSB is widely used to sheath roofs and to skin the exteriors of houses. If you feel the need for sealants, lay a bead of 100% silicone or adhesive silicone before laying the sheet down and make sure the bead is towards the edge of the bottom sheet. A 1/8-inch space between adjacent panel end and edge joints is recommended, unless the panel manufacturer indicates otherwise. One option is to try some test fasteners in the OSB. If using asphalt or fiberglass shingles, postpone shingle installation as long as possible. It is true as the price of every OSB board is around $15 – $20 per sheet (4×8 sizes). It's quick, easy, low cost, and you can do it yourself. Each material has its similarities and differences. There are two ways you can keep reading: Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. For vaulted or cathedral roof construction, provide a free ventilation path from eaves to ridge between all rafters. OSB roof sheathing – about 60% cheaper than standard plywood.. Leave a 3 mm (1/8 inch) gap between the OSB panels to allow for expansion. Working with plywood or OSB sheathing is a pretty straightforward process, but smart techniques can make the job easier, faster, and safer. The screened surface also provides a little more traction for construction workers during installation. In this case, carrying a sheet or two up a ladder can be the easiest way to do it. Having said that, it is very important that the sheathing be installed with the strength axis perpendicular to the trusses/rafters. Take the roof's total square footage and divide by 32. In the U.S., it is almost always composed of wood—usually OSB (oriented strand board) or plywood. Pro Builder is an advertisting supported site and we noticed you have ad-blocking enabled in your browser. 1. A gabled roof is one of the easiest types of roofs to build and cover, but sometimes these structures contain a two- or three-story expanse of solid wall underneath each gable. Use a 10d box (0.128-inch-by-3-inch) nail as a spacer to gauge 1/8-inch edge and end spacing between panels. Fasten panels in rows across the width, continuing this sequence along the length of the panel. Thicknesses range from 5/16 to … In high-wind areas, more fasteners may be required. One sheet = 32 ft². From responsibly sourced and sustainably managed forest resources, the Company produces lumber, engineered wood (OSB, LVL, MDF, plywood, particleboard), and other products including pulp, newsprint, wood chips, and renewable energy. Do this until the entire roof is covered. Use temporary fasteners at corners if needed to square panel on framing. Trusses or rafters should be shimmed as necessary to provide a level nailing surface. Spacer-type panel edge clips are available from some manufacturers. Most buildings need roof sheathing to support the roofing material and add rigidity to the rafters or trusses. What is roof sheathing? After receiving a few estimates, some (or all) of the roofing contractors propose to tear off your existing roofing material and re-sheet with plywood. • Lay sheets in the opposite direction to the prevailing winds. Most OSB suppliers have a load/span table giving a guide to the spacing of timbers for different thicknesses. Stagger the panels over the roof with 2 supports between panel ends. Avoid Putting OSB on Wet Roof Trusses. One 4-by-8-foot sheet of OSB or plywood is 32 square feet. Start at the lowest edge of the roof and roll out the felt at right angles to the direction of the full. If the top chords of trusses or rafters are warped or bowed, install blocking to straighten. ALL RIGHTS RESERVED, The bookmark icon allows you to save any story to your account to read it later, Tap it once to save, and tap it again to unsave, 5 Steps to Proper Roof Sheathing Installation, I’d like to receive the Pro Builder Daily Newsletter, 10 New Roofing Products to Spruce Up Home Exteriors, New Retrofit Design Guide for Metal Roofing, More articles about roofing and roofing products, The Quarantine Crawlspace: From Mold to Moisture Management, Home Prices Jumped Double-Digits in December, Highest Pace Since 2013, How to Navigate Appraisals Amid Volatile Building Material Prices, Next Generation of Renters Flock to Country's Heartland, The Dilemmas Builders Face With Home Building Technology, 2021 NHQA Winners: 4 Home Building Companies Striving for Better, Online Leads Account for 51% of Home Builder Sales. It’s simply “the lesser of two evils,” according to Lipinskiy. For example, it does not have voids or knots, or gaps and laps. Bulk pricing for 1/2 inch is $22.37 per sheet, and you need to buy 70 sheets. OSB is lightweight, relatively inexpensive, and strong enough to resist bending or breaking should someone walk on the roof. Avoid standing between framing, which can induce panel deflection. We’ve collected our best articles and videos on the topic to help you out. OSB is now the most-used sheathing and subflooring material for new roofs and roof replacements. Roof leaks, of course … but also improper attic ventilation can cause condensation in the roof deck that can cause the OSB to weaken. Fasteners should be 3/8 inch from panel ends and 3/8 inch from panel edges (see hints below). • Start laying sheets over the gutter with 6 cm overhang (maximum). The thickness of OSB that you need varies on where it is used in a building. This basically calculates the number of sheets needed for a Gable roof. It is a long document with many parts and subsections. Tie a rope around the OSB and pull it up onto the roof. It differs from commonly used plywood in many aspects. This how-to article is part of the Builder Tips series of publications from APA - The Engineered Wood Association. Avoid Butting OSB Panels Tightly. Note that these are minimum code requirements, which have been found to be adequate under most normal circumstances. From the 2012 IBC (International Building Code) Table 2304.6.1 – over framing spaced 24 inches on center, 7/16” OSB fastened with 8d common nails six inches on center at the edges and in the field will support a maximum design wind speed (Vult) of 110 mph (miles per hour) in Exposure B or 90 mph in Exposure C. Table 2304.7(3) gives the 7/16” OSB the ability to carry a roof live load of 40 psf (pounds per square foot) … Pro Builder’s Senior Editor Mike Beirne decided to…, A look at cold joints in concrete and how to prevent them, A first-person account of the annual show home’s construction, The annual National Housing Quality Awards recognize four home builders for their commitment to continuous operational improvement, More builders and investors are testing the waters of the single-family build-to-rent sector as consumers seek affordable housing options and to lease rather than buy.