The actual answer to all of these questions is going to be, ‘it depends’, but I will attempt to explain the factors involved that will affect the issue in question. My hope is that it will arm you with enough knowledge to help you in receiving a fair price and proper service expectations when receiving estimates for your new roof.
How much will a new roof cost? Of course all new roofs don’t cost the same, even on a ‘per unit’ scale. There are a number of factors that will affect the cost of a new roof. The most obvious will be the size of the roof. A bigger roof means more materials and more labor to install those materials and thus, increased cost. The second most evident thing will be the roofing product to be installed. Laminate shingles cost more than three-tab shingles. Cedar shakes cost more than laminate shingles. Slate tiles cost more than cedar shakes. Like most things, the fancier and/or more durable you want your roof, the more it’s going to cost.
There can also be significant differences in cost of similar components. Asphalt shingles can range from a relatively low cost ‘off-brand’ three tab product to the premier manufacturer’s top-of-the-line designer products (see some options here). Generic versions of things like roofing felt and ice & water shield can be purchased (like buying the store-brand ketchup) or you can pay-up for brand-name versions (like buying Heinz). Of course the brand-name products may have features and benefits that you think you want or need, but in many cases the generic products may well suffice.
Other factors that will affect the labor cost of a new roof will be the steepness of the roof, the height of the roof (in stories) and the number of layers of roofing already installed on the deck. Labor will be increased if the home does not have good access to stage and load materials and dispose of debris. Also some houses, because of their design, will have additional detailed work and/or may require additional ice and water shield which can make the installation of these roofs more expensive. There will also be increased cost if repairs to the wood deck are necessary.
How long will it take to install the new roof? A lot of the same factors that affected the price of the new roof will also be important aspects of how long it will take to complete the roof. These include the size of the roof, the steepness, access and height, the amount of penetrations and detail, the number of layers of old roof to be torn off and any repairs that are necessary to the deck.
The size and coordination of the crew installing the roof will also play an large factor in how long it will take. Of course when it comes to roof installation, speed shouldn’t be your major consideration. You don’t want your roof open to the risk of rain for any longer than it needs to be and you don’t want to live in a construction zone any longer than necessary, but you definitely want a roofer that is going to take enough time to do the job correctly. That being said, just because a roof is completed quickly doesn’t mean it wasn’t done right. I’ve seen large well organized crews that can do a great job getting a large, complicated roof completed successfully in one day.
How long will my new roof last? As you might imagine, the different roofing materials will all have different life expectancy. If I were ranking them from shortest life span to longest I would probably go: low-slope roof materials (I’ll save ranking these for another entry), asphalt shingles, cedar shakes/shingles, metal, tile, slate. Within these categories there is going to be some variation as well. Inexpensive three-tab asphalt shingles aren’t going to last as long as heavier laminate asphalt shingles. It’s also probably no surprise that the quality of the original installation is going to play a part in how long you can expect a new roof to last.
Another big factor in how long a roof will last is, where in the country is it located and what seasonal conditions exist there. The more moderate the climate the longer you can expect a roof to last. Hot summers, cold winters, high winds, high precipitation and humidity can all be detrimental to the life of a roof. Things like roof color and roof steepness and sun exposure can also play a part in how much environmental factors affect the life span of the roof.
Other factors can include: the effectiveness of attic ventilation, maintenance performed on the roof system (or lack thereof), the amount of foot traffic on the roof, other things coming in contact with the roof like tree branches, or even the original design of the home.
What sort of maintenance must I perform on my new roof? This will largely depend on what type of roof is installed on your home. Almost any low-slope product is going to require annual if not semi-annual inspection and maintenance. You need to be consistently clearing debris, making sure scuppers and drains stay clear, checking the seal on seams and around penetrations and at all terminations. For most sloped roofing applications the need for maintenance will be greatly reduced unless you are in an area where things like leaves, pine needles, etc. tend to accumulate on the roof. If that is the case then you still want to get up there or get someone up there at least a couple times a year to get that stuff cleaned off of there. If that isn’t the case you can likely get away with an annual check or even once every two or three years, just to touch up caulking and make sure there isn’t an issue starting to develop that needs attention before it becomes a leaking concern (like lifted or missing shingles, deteriorated flashings or missing caps and covers).
Again, the qualities of the roof itself are going to dictate how concerned you need to about roof maintenance. The larger and/or the more cut-up and complicated the roof the more areas there will be for potential problems. Roofs with lower slope are getting less help from gravity to drain and may require more maintenance (even if your roof only has one small area with low-slope you’ll need to increase the frequency of maintenance for that area) . As time goes on needed maintenance will likely increase, so the older the roof the more consistently and thoroughly maintenance must be performed to optimize roof life.
So as you can see, while these questions are very difficult to answer in a general sense, if you can know a few basic facts about your roof you should be able to get better answers to all of them. These would include the size of your roof (in squares or square feet), the pitch or slope of your roof, the type of roofing materials installed on your roof, the number of layers of materials already on your roof, the height of the roof, the age of the roof and the history of any past problems with the roof.