al roofs must be laid flat on a

2021/05/21

Metal roofs must be laid flat on a vapor barrier because steel will condensate if theres any air space underneath it. E-Foil or foil faced, bubble wrap type, reflective barrier insulation can also be used as a cushion between the existing roof and the new metal roofing. This product is in stock at my local lowes and I would only need two rolls of it. The airspace will also allow natural venting to take place. They provide excellent protection against the elements, but in many cases, rain and hail sound very noisy under a metal roof. The purlins give the installer a flat surface to install the metal roofing panels down to, without the irregularities a shingle provides. Check with yours before you make any decisions or start your project. More information here https://www.metalroofingsource.com. He said he would lay the metal right over my current shingles. From your response, the contractor is right with exception of some sort of underlayment. To protect your home during the installation process. They do create a thermal break to help minimize heat transfer from the metal to the roof deck. In some areas building officials only allow a re-roof over one layer of shingles. Some areas will only allow re-roofing over one layer of shingles while others will allow over two layers. There are also some disadvantages to installing metal roofing over shingles that youll want to know about before starting. Contact your local roofing company to learn more. Feel free to browse our Installation Manuals for more information. Also, try not to use nails anymore because screws work much better. This is the fastest way to install but it doesnt provide the flattest surface for metal roofing installation. One big advantage to metal roofing is that it is light weight, which makes it the perfect material to be installed over an existing shingle roof. metal underlayment roofing networx All Rights Reserved. Sitemap: HTML | XML. Take advantage of the air space and add in rFOIL and block up to 97% of radiant heat transfer! There are two main methods when installing metal panels over shingles. You can either leave the shingles on or put down felt paper during new construction. Metal Roofing Installation, Questions and Answers. If a self-adhering underlayment is used, it must be a smooth surface product rather than a granulated surface product. Many of them will allow one or two layers of shingles, but no more than that. Section 1511.3.1 of the 2018 International Building Code (International Code Council Series) 1st Edition states, The installation of a new roof covering over an existing roof covering shall be permitted where any of the following conditions occur2. Qualifications: More than 20 years of experience in residential and commercial exterior remodeling. More than likely they won't just come out and say yes. All of the edges must be wrapped with flashing, which improves the appearance and provides resistance against rain, snow, and wind. Always make sure that youre adhering to the more stringent of either building code requirements or manufacturer specifications. Whatever method you decide on, you want to make sure you, or whoever you pay to have it done, does it the right way. COPYRIGHT 2007-2022 | TRI COUNTY METALS - ALL RIGHTS RESERVED. This method has its benefits as well. "}},{"@type":"Question","name":"Do I need underlayment for a metal roof over shingles? The second is that the shingles provide an extra layer over your home, which helps insulate it further. But you might be wondering what the advantages and disadvantages are and what to keep in mind during installation. In that case, the old shingles should be removed or battens should be installed. Metal roofs can be much more expensive than shingles. What is the best way to hold the underlayment down, roofing nails? This involves putting down vertical battens first, attaching them through the roof deck to the rafters. In fact, they can last for about 40-70 years depending on the material. "}},{"@type":"Question","name":"How to install metal roofing over asphalt shingles","acceptedAnswer":{"@type":"Answer","text":"Whether youre looking to install a steel roof over shingles or another type of metal, its a good idea to learn the know-how. They also serve as both a slip sheet and an underlayment. If you would like to reply to this thread, please These scratches can damage the metal roofing panels and lead to premature failure of the roofing system. This can cause higher moisture levels in the attic. I guess my question is, what is the proper process for installing metal over shingles. This installation method also allows you the flexibility of adding a radiant barrier under the metal roof to help with heat transferring into the house, which should help the air conditioner from running as much. We also see ice and watershield underlayments being used where required by code, usually on the roof perimeter and up the valleys. Underlayment prevents that from causing a problem. Our Multi-Rib panel gives you the option to apply directly over shingles, no tear-off required! This is more expensive but will also be higher quality. The purlins also create an air space, which is great for insulation. For this reason, its usually recommended that you remove the shingles on your home before installing a metal roof. Here are links to videos on ventilation: http://www.asktoddmiller.com/roofing-help-videos/buying-a-new-roof-part-4-ventilation/ It is required by the International Building Code. Signs may include buckling tresses or sagging decking. Some areas will only allow re-roofing over one layer of shingles while others will allow over two layers. Along with saving the cost of completely removing the existing roof, installing a new metal roof over a current roof also brings the benefit of additional insulation above your home to prevent heat and cool from escaping. For many years, the standard underlayment beneath a metal roof was 30-pound felt. An informed customer is the Best Customer! Building officials in some areas will only allow a re-roof over one layer of shingles, while officials in other places may allow you to place the roof over two layers of shingles. The first way is to run new underlayment over the existing shingle roof, completely covering the old roof. As a great option to the expense and bother of battens, there are concealed fastener metal shingles, shakes, and tiles available. Many of them also come with the ability to resist fire (whether its a lightning strike or a wildfire) and withstand a hail storm without taking damage. When you install your new metal roof over an existing shingle roof, you immediately save money that normally would be spent to have the old roof torn off. And since we mentioned insulation, we should also mention that metal roofs are heat-blockers they reflect heat away from their surfaces rather than absorb it. I kind of want to know what to look for and what kind of questions to ask the contractor. Metal roofing depends upon precise flashing and metal fitting for watertightness. I normally suggest a layer of one of the higher quality synthetic underlayments, and ice and watershield if required by code. So when we talk about metal roofing over shingles, how does it work? It can also help avoid roof top ice dams in the winter. ","acceptedAnswer":{"@type":"Answer","text":"Yes, its possible to put metal roofing over shingles. Metal roofing weighs less than one pound per square foot. Contact your local roofing company to learn more and see what they can do for you. Then, you can pitch the warranty after about five years. So, first and foremost, its critical to choose the right product and install it per manufacturer specifications. The first is to apply an approved underlayment over the old shingles. We are committed to producing quality products in a timely manner and pride ourselves with friendly personal customer service. While sealants and adhesives may be used, they are as secondary back-ups for protection against water infiltration. If your new metal roof is installed over composition shingles, the rough surface of the composition shingles can scratch the back of the metal panels as they expand and contract with temperature changes. Knowing how to install a metal roof over shingles is important for a homeowner whether theyre looking to do it themselves or hire professionals. If your metal roof is to be installed over solid decking or over existing shingles (an environmental benefit), a layer of quality underlayment between the two is essential. By design, some metal roofs MUST be installed over battens, some MUST NEVER be installed over battens, and some can be installed over battens OR solid decking.

You also could install a corrugated through-fastened metal roofing product and probably not have issues. One effective way to use battens is to cross batten. Next, they provide a good surface for the roofing installers to work on. If you research how to install a metal roof over shingles, youll find that you cannot put a metal roof over three layers of shingles in most cases. Choosing the best roofing material for your home is the first important step in ensuring that you have the highest quality roof possible. Here are four more: If youd like to know more about metal roof installation or metal roofing in general, contact the experts, Advanced Aluminum of Lakeland, FL. However, the shingles expanding and contracting can cause damage underneath the metal roof over time. For one, you will need to check with your local building department and ask if this is an approved installation method. If youre installing a metal roof over asphalt shingles, the shingles may be able to act as an underlayment for the roof. Customer service and pricing available from 8:00 am to 5:00 pm MST Monday Friday. Were going to break them down, so you know what to look out for. Can you imagine screwing a metal roof, or anything for that matter, into rotten wood? "}},{"@type":"Question","name":"Can Metal Roofs Be Installed Over Shingles? Maybe, but have you considered your other options? More than likely the screws won't hold and that is something you definitely don't want happening if you want your roof to stay on during one of those afternoon thunderstorms we get here in Florida. Over time if there wasn't a buffer in between, the shingle granules would wear away at the back of the metal roofing panels. And, again, if you have good attic ventilation and insulation, those things alone are very helpful and can be more than adequate in most cases. If its slightly windy, keep the steel downwind from you, so a gust of wind doesnt knock you over. This means the extra insulation from your shingle roof will not act as a heat trap for heat emanating through your metal roof. Metal roofs have increasingly become a more popular option for homeowners due to their reputation for longevity and curb appeal. If they allow you, contact your local roofing contractor to see what they can do for you. Metal, although super-strong, is very light, weighing less than a pound per square foot compared with as much as four pounds per square foot for asphalt shingles. Also, consider ice guards even if you dont have gutters. Theres already plenty of advantages by choosing a metal roof, and theres even more when you decide to put a metal roof over shingles. We have decades of experience when it comes to installing this type of roofing, and we can actually custom-make every panel for your project. Some counties and municipalities require you to remove the existing roof regardless if it is the only layer of roofing on your house. Did you know you do not have to remove your shingles to put on a metal roof? Metal is the best choice due to its very low weight per square foot and its unique design. Next up: Where to go for more information. The disadvantages include: If you choose to install metal roofing over shingles, there are certain things you must keep in mind. Asphalt shingles can weigh up to four pounds per square foot depending on the brand. That is a good thing. This provides a couple of benefits: The first one being that the new underlayment will act as a second line of defense in case water were to somehow get underneath the metal roof. They can withstand almost any type of weather condition to keep your home safe, comfortable, and dry. ","acceptedAnswer":{"@type":"Answer","text":"If you wish to install metal roofing over shingles, its recommended to do it one of two ways. I hope this article has been helpful. Contact your local roofing company to learn more. What does it do and is it really necessary? Put the steel down directly on a vapor barrier. Not only do they look beautiful and unique, but theyre also designed to last decades longer because of their durability. Before you get started on your project, though, you will need to check with your local building department to see if theyll allow you to. The first is that it helps you save the labor costs of removing the shingles and prevents them from being thrown into landfills. If you were to put too many layers of roofing materials on a house, there would be a good possibility of the trusses failing. Standard tar paper has a tendency to stick to the back of metal roofing. You should have your roof inspected by a professional roofer to check for the following: In addition to checking the condition on the current roof, you, or your roofer, should confirm with the county that more than one layer of roofing is permittable. If your shingle roof has leaks, youll need to inspect for rotting rafters or sheeting.

This could include things like sagging decking or buckling trusses. For answers to your questions about the need for underlayment on your new roof, contact McCarthy Metal Roofing Systems, your local metal roofing experts. The reason why this is important is because a shingle roof is granulated, very similar to sandpaper, and as the metal expands and contracts due to weather changes, the metal will actually move. If youre installing a metal roof over asphalt shingles, the shingles may be able to act as an underlayment for the roof. The Florida building code, which is the minimum building standards that buildings have to be built to, including roofing, says that you can't have more than two layers of roofing materials on a residential house. ","acceptedAnswer":{"@type":"Answer","text":"There are a couple of advantages when it comes to installing metal over shingles. Check with yours before you make any decisions or start your project. Certain weather conditions may generate condensation on the back of the metal roofing panels. A home with limited attic ventilation is at HIGH risk that moisture originating inside the living space can migrate to the attic and cause condensation there. If there are any signs of problems caused from the previous roofing weighing too much, they must also be addressed. Condensation will lead to mold, etc. Get a FREE QUOTE: Click or call 919-900-1100. Shingles can create irregularities along the surface. Thanks! And, of course, if your old shingles are removed, it is very apparent why underlayment would be necessary to keep water out of your home while the roof is being installed. I have done research and know that this is very common. Your message has been sent You will most likely never have to purchase another roof again in your lifetime. This is more expensive but will also be higher quality. The contractor that quoted me said that he has always just screwed the metal directly to the decking on top of the shingles. It doesnt matter if the air space is a half-inch or six inches because the condensation factor will remain the same. Designed by Elegant Themes | Powered by WordPress, Please call us toll-free at 1-877-833-3237. with any questions or quote needs! Titanium is probably one of the more well known underlayments, but there are a myriad of manufacturers. The new synthetic underlayments do not have this problem as their design far exceeds the felt paper standards. However, the shingles expanding and contracting can cause damage underneath the metal roof over time. If you do not have an Ask the Experts forum user account, While its cheaper to purchase shingles (which is why most homes have them), metal roofing may provide you with better value in the long-term. Yes that is typical of what is often used. Everything I see on lowes website is very expensive. First, they are required by building code. But heres one more thing for you to consider: Do you realize that if you select metal roofing that this will likely be the last decision you make about the roof of your home? The resulting vertically oriented chambers can then be ventilated by bringing fresh air in at the bottom and exhausting it out at the top. and our manager will contact you shortly. Finally, if a structure has very limited insulation and ventilation (especially ventilation) in the attic, battens can be helpful, especially if a vertically seamed metal roof is being installed. And since it reflects heat from the sun, it can help you save significantly on energy costs. Expansion and contraction of the roof panels could then damage the underlayment. Kynar 500 Explained How Can Metal Roofing Last for Decades? However, cross battening significantly raises the roof level. The reason for this is so when the metal roof gets installed, the screws have something to bite into. HI, I recently had storm damage to my shingle roof. This should be obvious, but make sure you wear gloves! Thanks for all the help this far. Does that sound like adequate ventilation? PA #PA077391 | NJ #13VH09841400 | DE #2014100818 |. If youre considering getting a metal roof, you may be wondering if you can install it over shingles. And, even if the metal roof is installed on battens or purlins, there should still be an underlayment on top of the roof deck beneath the battens. The purlins are screwed or nailed down to the roof deck, depending on how the metal roofing manufacturer has testing for their roofing panels, and then the metal is installed to the purlins. And, keep in mind, for residential applications, I never suggest installations over battens unless there is a solid deck beneath the battens. Its an easy way to prevent cuts on your hands. All roofs need an underlayment. This is not good. They will be able to tell you what you can and can not do. Metal roofs over shingles also present a number of problems. Now as to the potential benefit of battens. The typical underlayment being used today is a low weight polymer based synthetic underlayment which lasts longer and is easier to install than the old asphalt based felts or tar papers. You may have shingles now, but are shingles your best choice for the years to come?

We manufacture top-grade metal roofing products used by leading contractors across the Lakeland region. If they allow you, contact your local roofing contractor to see what they can do for you. But first, here are a few precautions about the underlying material: Even with the best warranties, it may be hard to track someone down after 40 or 50 years so they can assess your roof and write you a check for any damage. A layer of soundproof insulation can help, but it adds to the cost even more. Your attic ventilation and insulation will also help with summer energy efficiency. I had a local contractor (he was recommended by a few people I know) come give me a quote. Print, complete and email or fax us your order. That can be something that some homeowners want to avoid due to possible issues developing over time with the fasteners. They include: Like most other things, there are a few disadvantages of choosing metal roofs. This means gutters will have to be re-hung. Recent years have seen the development of many new underlayments generically called synthetics. ","acceptedAnswer":{"@type":"Answer","text":"In simplest terms: Yes, you can install a metal roof over shingles.

In almost every case, the answer is yes, you can lay down a new metal roof over an existing shingle roof. As the metal roof heats up in the summer time, the added air gap in between will act as a buffer instead of the the metal heating up the below shingle roof. I have been getting opinions from people that are not experts and everyone seems to have different opinions about everything. create one When you decide to go ahead with this project there are a couple of precautions regarding the underlying material: A layer of underlayment installed on top of the existing shingles will help keep the granules of the old shingles from rubbing against the back of the metal and causing possible corrosion. Also I have heard a lot of horror stories about the attic not being properly ventilated, causing condensation inside the attic. Mid-Florida Metal Roofing Supply has been in the business for 13 years. Privacy Policy. These products usually have an integral airspace or an insulated cavity between the metal and the roof deck. The first is to apply an approved underlayment over the old shingles. Another added benefit is that the layers of your old roof will further insulate your home. Our profiles can also be ordered in custom lengths up to 21ft.

The first is that it helps you save the labor costs of removing the shingles and prevents them from being thrown into landfills.

This has very positive results as far as keeping heat out of the attic. However, there are some things that you will want to check out before doing it this way. They can also sustain wind gusts up to 140 mph. Also, dont go up on the roof if its windy. This creates a thermal break which is very similar to a vertically seamed metal roof installed on battens. Should their be a moisture barrier or some kind of moisture wrap put on top of my shingles? We are here to help. One issue with 30-pound felt was that, because it is an oil-based product, it would sometimes stick to the underside of the roof panels during hot temperatures. But its always best to check with your local building and zoning departments to make sure they approve metal-over-shingle installations. And, a great alternative to battens are the metal shingles, shake, slate, and tile products which have an integral dead air space between the metal and the roof deck, serving a function similar to that of battens. In most cases its not even an issue if you are only going over one layer of shingles. Referencing Section R907.3 of the 2006 International Residential Code Book best answers this question, it reads as follows: Complete and separate roofing systems, such as standing seam metal roof systems, that are designed to transmit the roof loads directly the buildings structural systems and that do not rely on existing roofs and roof coverings for support, shall not require the removal of existing roof coverings.. Founding farther of Legacy Service. Fortunately, in most areas, it wont be an issue if youre only going over one layer. The metal will be attached to at least 3/4 purlin and 1/2 plywood instead of just 1/2 plywood, which should make the overall roofing system stronger. https://www.google.com/search?q=high+temp+underlayment&ie=utf-8&oe=utf-8#q=high+temp+roofing+underlayment Other areas will allow you to re-roof over two layers.

But probably the best benefit that comes from using purlins is the air gap it creates between the metal roof and the existing shingle roof. However, if you choose a metal roof that is either light in color or has reflective pigment in the paint, that will be very helpful as well. Is it to keep the back of the metal from being scratched by the shingles? The second way is to install 14 purlins over the shingles. We look forward to speaking with you! In warmer climates beneath metal roofs, especially metal roofs that have direct contact with the underlayment, high temp underlayments are commonly called for. Written by LegacyUSA Team. Metal roofs over shingles also present a number of problems. We specialize in custom profiles serving a wide variety of needs in the construction industry. In fact, a metal roof thats built properly will be able to handle anything Mother Nature throws at it. 919-900-1100 So, why are underlayments necessary? "}},{"@type":"Question","name":"What is the advantage of a metal roof over shingles? "}},{"@type":"Question","name":"Can you put a metal roof over three layers of shingles? This can cause the paper to tear when the metal roofing expands or contracts as it is designed to do. Interestingly, over the past several years, we have seen significant changes in the types of underlayments being used. Fact is, there is always a chance that during a particular wind-driven rain storm that may happen only once every five years, you may bleed a little water through a flashing or some other area of a metal roof. My attic has open vents on each end and a blower in the roof that is hooked to a thermostat. I am no where near being a roofer or carpenter, that is why I am here. How many layers of roofing are already on your home. The purlins allow for a flat surface for the metal panels. Next, I highly advise the use of a layer of underlayment over the old shingles or decking whether or not battens are used. Get an estimate or schedule your appointment today, Home | Our Blog | How To Install Metal Roofing Over Shingles, Reviewed by Tomas Kalkys. Even with their durability, which helps increase value and balance over the expense over time, many homeowners simply cant afford to install metal. However, youll want to check with your local building department before you make any decisions. Send Us an Email, Copyright 2021. Remember that if you choose to install metal roofing over shingles, its best to add an underlayment or purlins. So, you need a new roof. Is there anyway you can send me a link to a commonly used polymer underlayment? Youre probably wondering about the cost to install a metal roof over shingles. 1250 Kirkland Road, Suite 103 Depreciation may also significantly reduce the amount youd receive. This is the fastest way to install but it doesnt provide the flattest surface for metal roofing installation. ","acceptedAnswer":{"@type":"Answer","text":"If you research how to install a metal roof over shingles, youll find that you cannot put a metal roof over three layers of shingles in most cases. Knowing how to install a metal roof over shingles is important for a homeowner whether theyre looking to do it themselves or hire professionals. Metal roofs over shingles will also provide an extra layer covering your home, helping to further insulate it. From there you have a couple of different installation methods to choose from, either fastened to the existing roof or through the use of purlins. Remember that if you choose to install metal roofing over shingles, its best to add an underlayment or purlins. When would you like this request to be completed? One thing to remember is that many of the products that are installed over battens have exposed fasteners. Contact your Mid Florida Metal Roofing Representative for more information on your new metal roof! Not only are they visually appealing, but theyre also much more durable than shingles. If there are any existing roof leaks, you need to address them and replace any rotten sheeting or rafters. We also manufacture an extensive list of flashing profiles to meet any standard or custom application as needed. My insurance has agreed and quoted me a price to replace my shingles. The dead airspace in the hollow beneath these panels acts like the dead airspace between two panels of glass in a thermal pane window. Adding a metal roof over existing shingles doesnt significantly increase the overall load for the home structure to bear. If youd like to learn more about metal roof replacement, contact our Legacy Service team today to schedule an appointment. ","acceptedAnswer":{"@type":"Answer","text":"Youll need to check with your local building department to see if you can install metal roofing over two layers of shingles. Over time the granules from the shingles could imprint on the metal panels, the underlayment helps prevent any imprinting. Chances are, you currently have a shingle roof and you are debating whether to make the switch to a metal roof. Are you interested in financing your project? Even if there is an existing roof in place, it is getting a lot of foot traffic while the new metal roof is installed as well as having nails pounded through it. Otherwise, they would be found everywhere! Complete and separate roofing systems, such as standing-seam metal roof panel systems, that are designed to transmit the roof loads directly to the buildings structural system and that do not rely on existing roofs and roof coverings for support, shall not require the removal of existing roof coverings.. Fortunately, in most areas, it wont be an issue if youre only going over one layer."}}]}. These include the appearances of natural cedar shakes or stone. So, if you plan those improvements now, do not do something to the roof that could make it more prone to condensation when those other things are done. When adding the screws, they should be spaced between 24 and 30 inches and skip every other rib to create no more holes than necessary in your roof. However, youll want to check with your local building department before you make any decisions.

Were going to answer that question in this blog, so keep reading or give our Legacy Service team a call at 215-798-9790 if youre considering a metal roof replacement. In some cases, local building codes may require a more fire resistant underlayment or may even require the use of self-adhering ice and water shield type underlayments over the perimeter and valleys of the roof. The answer is: Yes you can. And by doing so, you save in the labor and hassle of tearing off the old roof and you wont be contributing to filling our landfills. Ventilation allows that condensation to drain and/or evaporate without reaching your homes structure. (2021), Metal Roof vs. Shingles Cost Comparison (2021), 5 Reasons to Roof with Centura Metal Shingles, How to Convince Your HOA to Allow a Metal Roof, Shipping, Offloading, and Damages Information. A lot of elements play a role in maintaining the integrity of the roof, but as a homeowner, the most important components to pay attention to are the underlayment, ventilation, and material.