Patio Roof Maximum Beam Rafter Spans Beams. Mt Washington, Lo-Chill: 200-400 Hrs, So, 6 Patio Cover Types to Shade You in Style, How to Add a Backyard Shed for Storage or Living, Houzz Tour: See a Maine House With a $240 Annual Energy Bill, So You Bought a Cave: 7 Ways to Open Your Home to Light, Knotty and Nice: Highly Textured Wood Has a Modern Revival. New, light, pulled down wallpaper border, new paint, new trim, new doors, widened doorway to the kitchen, new floor, some electrical work and a LOT of damaged wall work. Except for the furniture, this is what the dining room looked like before and after. These block the AM sun at breakfast time, year around, so the pergola rafters don't have to.3. Googled 'LOUVERED ROOF PERGOLAS'. The orientation of the house and proposed pergola should be checked against geodetic north. What are the dates for oppressive heat? You will find here all the considerations to know how things are done while constructing the Pergola. The lack of visual clutter allows your architecture and the backyard pool to shine. Notes: 1) Refer to general notes for information that is relevant for all span tables. Climbing flowers & fruit that may work in your area: Bougainvillea, Wisteria, a fast-growing vine with beautiful flowers i.e. If you are at all inclined to show the calculations, that would be MOST interesting. Remember that this site allows the direction of the sun to be disregarded. I think that part is all under control. Along the lines that plx8ss asks, to tell the truth, we are mostly in the house in the WINTER--Dec-March, or so. When the sun is exactly overhead the shade cast will be 5.3 inches wide. Coincidentally, this is also the angle where a solar panel produces the most electricity, and there are a lot of webpages covering that subject. (For sites at a higher latitude, both slant and direction muist be considered.). Thanks very much for the solar calculations, pls8xx. With the pergola orientated 12 degrees to the east of north, the length of the boards will vary little from perpendicular throughout the afternoon. mad_gallica:"Because at solar noon, the sun will be directly south.". The sun is so pervasive that it even bleaches car paint ... And of course, the salt in the air...". I'd love to hear how it went and what you would do differently, pictures too. However, I can see that near the noon hour, you're not going to get protection from the sun unless you have a 90*, or close to it, tilt. One might be tempted to optimize the design for the summer solstice. My question is really about how to get the maximum shade (solar design question). I propose to slant them as shown in the sketch because the AM sun is pretty much blocked by the banana trees, so the noon/afternoon sun is the more important to block. Thanks again to all who reply! Beam Size For Long Span On Pergola Decks Fencing Contractor Talk. it was moisture in the boards that was tricky. I recommend a tall pergola that runs the the width or 3/4 of the space. And then you can add decor very slowly and be sure not to go overboard. Who knows what will happen in ten years? To get this set, I zoomed the map on Hawaii. Location: Kihei Hawaii-- just about lattitude 20 degrees N, pretty much very sunny all day, every day, all year long.7. En savoir plus. Using trig, the vertical and horizontal sides are found to be 5.3 inches. However, I am more interested in being able to sit on the patio and also in preventing solar gain on the concrete of the patio--the patio bounces significant heat into the adjoining house, which is why I want a permanent structure. I * truly * thank in advance, anyone who answers, or who can point me in the direction of resources to get the answer myself. Next I'll show the calculations, if anyone is interested. pergola spacing calculator simply select any part of your pergola in 3d and use our pergola software tools to adjust the slats, rafters, rafter supports, columns, and more. If there are not decorative rafter end cuts, it may look bulky or clunky all the time. The answer is going to be 90, or horizontal, spaced with equal openings between the rafters. For the pergola beams shown in illustration, the Roof Load Width is the dimension representing half the rafter span plus any rafter overhang. If I'm understanding the setup correctly, it is a trick question. However, we do visit at SOME point in the summer, even if only for a week or two. In doing it this way you have close to optimum conditions for a much wider range of dates. At the poster's latitude, for a major part of the summer, at solar noon, the sun will be directly north. requirements of your chosen pergola shape or size. En continuant à naviguer sur ce site ou à utiliser cette application, j'accepte que le groupe Houzz utilise des cookies ou d'autres technologies similaires pour améliorer ses produits et services, me proposer du contenu pertinent et personnaliser l'expérience utilisateur. Also along these lines, I am not willing to build a traditional pergola, pretty to look at, yet pretty useless, because 2x8's set on edge will give very little protection from the noon-day in Hawaii, winter or summer. Luckily, NOAA has a site that will do all the heavy lifting....http://www.esrl.noaa.gov/gmd/grad/solcalc/. Below the graphic the first line contains the location. Should have thought of that first! Putting in a window and lining one wall with rustic looking pallet boards. I agree the final product may well look clunky. I think it's important that they not only look good, but feel soft and appealing for your family to use. Most are adjustable, but some are fixed. For one thing, lawn furniture would be more protected, and so a person could buy more comfortable cushioned furniture, because the rain would not spoil it. It seems like you would be better off to use a shade structure that is reconfigurable for the conditions of the moment. Based on a solar angle calculator I found on-line (link 2, below), on the summer solstice, the sun is basically overhead (~90 degrees) and on the winter solstice, about halfway down the horizon (~45 degrees).8. But this is mitigated for Hawaii by the surrounding ocean. Note that at 3:00 PM the shade width is 8.94 inches. If the pergola’s width is an odd number of feet, you will have an odd number of rafters; if it is an even number of feet, you will have an even number of rafters. This is indeed true, but the design for solar panels for optimum electricity is somewhat different than for shade to mitigate heat. I like pillows that can really be used! Pergola Beam & Rafter Sizes & Spans. 10kg/m2) Note: Fascias, gutters, downpipes, etc. With the shade width at 5.3 inches at solar noon, I then use the sun elevation data obtained from the solar calculator to apply an adjustment value for other times-of-day. Then I clicked the green pin at Honolulu (it turns red). It lasted for over 15 years. To calculate your Rafter Length for an attached pergola, it is Measurement A + 1'6″. The bad news is the answer is still the same - horizontal. While I can appreciate the attempt to remedy the problem with an approach like this, it seems to me you'll be creating another problem or two if solving this one. Different objectives need different designs. The patio to be covered by the pergola sits pretty close to square on a NSEW grid. And if you choose to remove the tree, a palm or cactus or from your area, with solar-uplights underneath for low-key, night lighting would be a smart addition. Also, Hawaii never goes to daylight savings time, because it is always on HST (Hawaiian Standard Time). Another problem with achieving 50% shade for this site at noon is that solar noon does not occur until 12:32 PM. What is your objection to a solid roof over all? Good job. Multiply this by 2 to give the distance in from this end and from the other end of the rafter at the opposite post, giving 8ft 2" or 2.50m. Looking at a shade width of 4.6 inches at 12:00 PM local time, the boards would have to be set on 9.2 inch centers to obtain the desired 50% shade at noon. Pergola Main Beams Span Building … Let me start by saying that I am * not * asking about the construction of the pergola (span/construction/setting the posts/etc.) For any spacing of the boards, the % of shade for a given time can be found by dividing the shade width by the spacing width. It could be a standalone, movable awning in lieu of a pergola, or a shade apparatus that is part of it. AS1684.2 and 3. South Beach, FL, can't quote exactly but meets sustained hurricane winds. Ends of rafters and beams shaped to reduce end grain exposure Ledger Rafter Lightweight roo˜ng (max. Need Help With Living Room: Colors, Windows and Furniture Arrangement, Need privacy taller than existing backyard wall. Had shade cloth over skylights in previous home. LINK 1: (old discussion of solar rafter spacing on this site) http://forums2.gardenweb.com/forums/load/design/msg060100401918.html, LINK 2: (Solar angle calcuator)http://solarelectricityhandbook.com/solar-angle-calculator.html. The second number is the angle from horizontal up to the sun, zero at horizontal, 90 degrees is directly overhead. Here are some trellis & pergola photos for reference:
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[houzz=], We are doing a small home office in one of our attic spaces. The rafters will also rest on the girders and perhaps also have notches in them. However, despite these advantages, I believe a solid roof would be a bit of overkill for me. So---with all that in mind, the exact question is: How to space and angle the rafters to cast the most noonday and afternoon shade? I'm not about to try and teach how it's done. Solar calculations by hand are tedious. The path to successful innovation is filled with great ideas that didn't pan out and became expensive white elephants. Since 12-inch spacing is an even foot, it becomes simple to place rafters on a pergola by determining whether the number of rafters will be even or odd. Based on the 2007 discussion about rafter spacing, I believe these to be the pertinent facts: 1. Throw 'em out when they get shabby, it's fun to select new ones. Finally, while a 90 degree slant (flat roof) would give the most coverage from the noonday sun, I think slanted rafters would be better for drainage and would weather less, and would look more like a pergola than a ramada. I suspect it is because of the solar gain (which is why I want permanent shade...). Excessive heat is an issue every single day around noon to late afternoon and even beyond. So, back to the original question which started this whole series of inquires: Anyone have some insight into the angle and spacing for latitude 20 degrees north to obtain about 50% shade at noon with NS oriented louvers on an EW oriented framework, (as shown in the original two sketches, first post of this series)? There is a 10' high wall, 10' due west of the area to be covered with pergola, this blocks the later afternoon sun--for about an hour or two before sunset.4.