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What size lumber would be recommended for the bottom chord on a truss to span a 30 foot clear span pole barn with a osb board and asphalt shingle roofing?
Ljpcar
Trusses are engineered components of a building, based on live loads, pitch, span, spacing, other loads that may be placed within the trusses, like attic storage, etc. If you're building to code and with a permit and will be inspected, you will need to present the engineering sheet that comes with a truss order. If you are building them yourself,(which is not legal in most jurisdictions anymore), you should at least work from a set of pre-engineered truss plans. The Extension Service, serving most counties in America, used to offer a book with an assortment of truss plans. I don't know if it is still available. You will find, however, that to build your own trusses you will invest more in nails and gusset material and lumber than it would cost to have them built by a truss plant. As to the size of the bottom cord on a 30' span, they can be sized from 2 X 4 up to 2 X 12, or even greater if they are timber trusses or will be used to support loads such as an overhead trolly. But each truss itself is a set of components all working together to achieve the desired strength, with the bottom cord being just one of those components. And the spacing and bracing of trusses to each other is of equal importance to achieve adequate strength in the building.
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What is the best way to shingle a peak with asphalt shingles?
The best way to shingle a peak with asphalt shingles is to stabilize boards along the peak for safety. Continue to shingle the asphalt shingles to the peak working from the bottom edges of the roof peak. Nail two nails on the lower portion on both sides to hold in place. Continue until finished.
What then is the rake of a roof?
The rake is the edge of the roof that is not the eave where water drains off. On this edge are the cut off ends of the roofing material as opposed to the bottom edge of the shingle, which is a factory cut. This edge does not exist if there is a hip, the inverse of a valley.
What is curled when talking about shingles for your roof?
Shingles curl up at bottom of shingle.
How do I repair a leaking roof?
One of the most important safety tools youll need is a good pair of rubber soled shoes. For a shingle roof, once you find the leak look for damage, a cracked or missing shingle may just need replacing. If no damage can be seen you will need to call a professional. To repair curled back shingle, use asphalt roof cement. In the summer a curled back shingle can to easily straighten out, but in the winter a shingle can become brittle. To soften a cold brittle shingle, careful use a propane torch with a flame-spreader nozzle. Apply heat only to soften, not until it catches fire. Once flatten apply roof cement generously to the bottom and edges and press firmly into place.
How do you install dimensional shingles over 3 tab shingles?
Complete instructions should be included on the shingle package, but essentially what you will be doing is placing the top of the new shingle against the bottom edge of the old shingle, assuming the exposure of the shingles is the same.
Does roofing paper go horizontal or vertical?
Roofing paper is laid horizontally, starting at the bottom edge of the roof with the next row overlapping the the row below it.
Why is it recommended that you put sand or pebbles at the bottom of a terrarium?
It is recommended that you put sand or pebbles at the bottom of a terrarium to allow drainage when watering plants.
The Importance of Roof Shingles?
Shingles that are put on the roof of a home are a covering with overlapping slaps. These slabs are flat and usually rectangular. Just one single layer should make sure that no water is able to get into the home because of the overlapping design. To apply them, you must start at the very bottom of the roof, and work your way up to the top. The edge at the bottom of each row goes over top of the previous line by covering roughly one third of that shingle. Each shingle is easily secured in place with a hammer and some nails. Some people may also use a nail gun to make the job go a lot faster. Others may even use a staple gun, but it is less recommended as staples may come back out. At the tip of the roof, there is a ridge where the two sides meet. At this ridge, there is normally a sheet of metal or plastic that covers the crack. On top of that, there are special shingles that are curved to be like a cap. Shingles have been made of many different materials. The most common have been asbestos-cement, slate, ceramic, and wood. Wood and paper-based asphalt are becoming less common because they are prone to being hazardous towards fire. Wood was mostly used when buildings were made almost all of wood, and in the European countries. It is also less used because it rots away in time. Fiberglass asphalt shingles are taking over the lead role. They are used on a majority of roofing jobs in homes. These asphalt shingles last longer when it is cold outside, but should be applied when it is hot out. The reason that are more durable in cold climate is because of thermal shock. This occurs when the temperature quickly changes by more than a few degrees. Shingles for the roof should be applied in the summer because the tiles need heat and sun so they can be sealed to the shingle below. So, before you even start, you need to make sure to know exactly which kind of shingle you are buying.
What is Mod Bit roofing?
Modified Bitumen Roofing is an engineered product for flexibility. Expansion and contraction from weather temperatures/humidity/dryness makes asphalt/bitumen/tar products crack when hardened/aged. On low pitched roofing systems, boxed curbs are built to house large penetrations in order to keep water out. As the roof meets these boxed curbs, a 45* slanted board (cant strip) is installed at the bottom junction, to allow the rolled roofing membranes to bend gradually. Even with the added cant strip in place, regular field membrane cap sheets (granulated roll) can break at the transitions, therefore a need for a more flexible roofing membrane. The modified bitumen products may be used on the horizontal planes as well as the vertical planes, for a longer lasting roof and a higher price.
Had roof vents installed along with new roof and is leaking from just below bottom of each vent causeing damage to your ceilings?
Call the contractor and have it fixed. Were they install correctly. Are all the vents leaking or just one? Were they sealed? A properly installed vent shouldn't leak even if it has not been sealed. The bottom edge may be under the shingle instead of on top of it. You should shingle to a point and then put the vent on and shingle on top of the nailing flange from one third to one half of the sides of the vent depending on where it comes on the rows.
Do you have to use wood strips on roof before metal roofing is applied?
Whether you have to use wood strips on metal roofing will depend on several things:The type of metal roofing. Most types of metal roofing do not require wood strips although strips can be used. Other types must be placed on wood strips, and some types of metal roofing cannot be placed on wood strips.Whether the metal roofing is going over an existing roof. if you are going over an existing shingle roof, you will need to put something between the existing roof and the metal roofing, such as wood strips or 30 lb felt.Wind requirements. in general, your roof will be more wind resistant by going down over the solid decking vs. the wood strips, which will not be as wind resistant.Ventilation. The use of wood strips will allow the panels to breath better, reducing the change of condensation (water droplets) building up on the bottom of the panels.Straightening out the roof line. You can shim wood strips up to reduce and eliminate sag lines in the roof if your plywood is wavy, or uneven.When installing the most popular 3' wide metal roofing, many contractors choose to install wood strips first, but in most cases, you don't have to.
How do you do asphalt shingle roofing?
It's good to have someone teach you the first time. It's worth the expense to pay someone to train you, since it's so easy to mess up a shingle job, then you have to live with a leaky roof.There are several things to watch for, such as the first course needs to be offset from another course of shingles.The tabs should be cut off the bottom course and the sticky surface should be near the drip-edge. Then the next course should align with the drip edge or hang over slightly. Plan on using a "chalk line" every 5 courses to make sure the shingles remain straight. Overlap a "half tab" on every shingle course. Make sure there are 2 courses UNDER any flashing metal or vent flashing. cut carefully around flashings to keep an even gap.MAKE SURE YOU USE METAL FLASHING on chimneys and any other vertical surface. Go up the side AT LEAST as high as the normal snowfall/ice dam potential.No nails should be visible, all nails should be covered by the NEXT course of shingles.If you do it right, your roof should need NO adhesive or sealant. Remember that water from the shingle above should ALWAYS fall on the next shingle, nothing else.You'll be far better off if you strip the old roof, repair any damaged or rotted wood, put down rolled ice dam protectant (instead of tar paper) and use the chalk line frequently, measuring an equal distance from the ROOF RIDGE down.Good luck.
