When looking into roofing costs, you will notice that there are a few key costs associated with roofing your property. The first cost is for tearing off your old roof. The second cost is the material for a new roof. The third cost is for installation. In this article, we provide a quick overview of these costs and the options you have when considering upgrading your roof.
Roofing prices are typically given on a ‘per square’ basis, where a square is a 10ft x 10ft section of roof (100 square feet). A one-story roof with a single layer of shingles costs between $100 and $150 per square to remove; a double layer costs $115 to $165 per square to remove; and a triple layer roof costs $125 to $175 per square to remove. These are the general costs, and they can increase or decrease based upon the pitch of your roof as well as the number of facets on your roof. To replace your roof with asphalt shingles for example, it will cost between $120 and $140 per square (slate and clay tiles, wooden shakes, and metal roofs typically cost between $1,000 and $1,500 per square). The above prices are for the tear-off and replacement materials. There will be additional costs for the roofer to install the shingles, and these will vary based upon the professional. Observing online studies, we can see that on a ‘per square’ basis, roof installations cost between $200 and $300 for labor.
Depending upon your local city or municipal ordinances, you may have different options to consider when re-roofing your house. Frequently, you are able to have more than 1-layer of roofing on your property (up to 2-layers of roofing in Pasadena, CA for example). Thus comes a decision point: should you re-roof over the top of your existing roof, or should you tear it off and start again? To answer this, we will provide a brief overview of the trade-offs with both options here.
Let’s consider the case where you have a single-layer of roofing at the present which has reached the end of it’s life. Simply adding an additional layer of roofing over your existing roof seems like it may be an obvious choice when it comes to re-roofing as it avoids the cost of tearing off your old roof (at least for the first layer). However, it is not as simple as that. When you add a layer of shingles over your existing roof, it will have a 20% shorter lifetime. Thus, if your asphalt shingle roof would normally last 20-years, it will now last a total of 16-years. Additionally, when you go to replace the roof the next-time, you will have to remove 2-layers of roofing, which costs about 15% more than tearing off a single-layer of shingles. Crunching the numbers on a 1000 square ft. roof, we obtain the following breakdown of costs:
Option 1: Add a second layer of roofing over your existing roof at $140 per square, for a total of $1,400 in materials and around $2,500 for labor ($3,900 in total cost). This roof will last for approximately 16-years, with a total per-year cost of $243.75. At which point, you will need to re-do the roof (tearing off 2-layers of shingles). The next time you redo the roof, the costs will include $1,500 for the tear-off, $1,400 in materials, and $2,500 in labor (for a total of $5,400). This roof will last for 20-years, with a per-year cost of $270.00. Thus, over the course of 36-years, this roof will cost an average of $258.33 per year. This cycle can be repeated.
Option 2: Tear off the original layer of roofing each time you do the roof. In this case, you would tear off the original layer of 1000 square feet of roofing at a cost of $1500. Then, you would require an additional $1,400 in roofing materials and $2,500 in labor installation materials. This brings the grand total for re-doing the roof the first-time to $5,400 and the roof will last for 20-years. At the end of the 20-years, you would again tear-off the original roof and replace it. This would cost $5,400 and would again last for 20-years. Thus, for 40-years of roofing this would be approximately $270 per year.
Given the above two strategies, the average per-year costs differ by approximately 4.5% (it is slightly more expensive to tear-off and replace a roof than it is to simply lay a new roof over the top of your old roof). Given this consideration, the key item to consider for you or your organization may be the issue of cash flow. Option 2 provides a uniform cash flow across the years. However, if you are currently in a cash-strapped condition, you may be able to buy yourself a 16-year time window by going with Option 1. Option 1 has a different cash flow where 42% of your expenses will come during the first re-roofing, and 58% of your expenses will come at the second re-roofing. This option could buy you or your organization some time if needed.
To conclude: If you have the capital, you may opt to replace your roof less frequently and tear off the shingles each time. If you are short on capital, you may consider going over the top of your current roof. At the end of the day, the choice is yours. We recommend you look into the details of each option and choose the option that best fits your current needs. This article is primarily meant to provide you with some information on the trade-offs, and to enable you to make your own decisions.