Roofing Replacement Basics
You truly don’t know how important your roof is until something bad happens to it. When the water starts to come through the ceiling and destroys your brand new TV, you know it’s long overdue for a new roof.
Replacing a roof doesn’t have to be difficult. With the right steps and materials, you can replace your roof with ease.
Basic Roofing Materials
Depending on where you live, it may call for different roofing materials than a different region. For instance, metal roofing can be used if you need fire resistance. Some regions may need Spanish-influenced tile tools. The roof pitch, which is the angle, also has an affect on the roofing materials you use.
Common choices for residential roofing are:
- Asphalt composition shingles : Has a flat appearance, cheap and obtainable. Most popular roofing material on the market.
- Wood shingles or shakes: Attractive but pricey, although durable. Not good for areas susceptible to fire dangers.
- Metal roofing: Fireproof and durable, making them more popular these days. Require special contractors and cost-effective in the long run because of its long life. Raised-seam panels and products that are similar to composite shingles are also available.
- Slate roofing: High-end roofing option and attractive, but heavy and expensive. Difficult to repair when damaged. Slippery to walk on.
- Composition slate: Made from 95 percent recycled materials, including rubber. Resembles slate and other stone tiles, but less susceptible to damage and lighter.
- Clay or ceramic tile: Common in places like Southern California and Florida due to it’s Spanish-style red tile roof. Gradually being replaced by composite materials and metal that follow the Spanish tile look. There are now other roofing materials available that mimic ceramic tile’s ability to slow down fire, with less weight on the roof. Also called half-barrel shingles.
Tear Off vs. Second Layer
There are pros and cons to applying a new layer of shingles over the old. It use to be a common practice to lay a new shingle roof over the old layer once or twice.
However, it is not allowed in some places and rather they require a tear-off of the previous roof. There are factors to consider on your decision:
- Weight: Consider that laying additional asphalt shingles can get too heavy for a previous roofing frame. This can be an issue, especially for older roofs. A triple layer of asphalt shingles is equivalent to one layer of slate shingles, which is extremely heavy.
- Telegraphing: You run the risk of having an unattractive roof if your existing roof has irregularities, as adding another layer over the existing one does not get rid of any issues such as bubbling, bumps and waves. It’s best to fix those problems first, then apply the new roof.
- Work and waste reduction: Layering reduces the work involved, as stripping off an existing layer and adding a new layer increases the work to the process. This is not an issue if contractors are doing the job, but it can be if you are doing it by yourself.
There are many factors that contribute to the cost of a roof. First, the materials you choose play a role, as well as contractors, the steepness of the roof (pitch), square footage and additional labor. Per square foot can also include the charge of demolition, waste disposal, permit fees and cleanup.
Average cost of different roofing options:
- Three-tab asphalt shingles:$7,000 to $12,000
- 30-year shingles:$9,000 to $15,000
- 50-year shingles: $11,000 to $20,000
- EPDM rubber: $8,000 to $14,000
- TPO or PVC membrane:$10,000 to $15,000
- Wood shingles:$14,000 to $25,000
- Steel shingles:$14,000 to $25,000
- Aluminum shingles:$15,000 to $28,000
- Standing seam steel roofing:$23,000 to $30,000
- Natural slate: $25,000 to $50,000
- Concrete tile:$20,000 to $40,000
- Clay tiles:$25,000 to $50,000
The best roofing season is late spring to early fall. Having a skilled crew working on your roof during the off-season can allow for lower costs without any potential weather disturbances.
Working on your roof during high season allows contractors to extend their work season if there are any issues you cannot control. When demand is low, you can enjoy lower prices and have work done in hours instead of days, all while having a well-coordinated roofing team do the job.
The Roofing Process
When hiring a roofing crew, it’s important to know the process and the jargon that follows. Usually a professional roofing job takes 3 to 4 days that goes like this:
All existing shingles are removed, deposited in a roll-off and goes in a dumpster. Damaged edges or old valley flashing are removed. Shrubs and plantings will have a protective foundation over them, while nails and metal objects are removed using a magnetic tool.
If the roof is in good condition, there will be minor repairs. New plywood or sheathing boards will be used on those that need to replace bad wood, but it depends on the roof.
Ice dam protection must be installed in regions that require it. A synthetic waterproof barrier, known as the ice guard membrane, prevents melting ice accumulating under the shingles which cause severe damage.
Asphalt roofing paper is laid down over roof sheathing. The roofing paper layer creates an inner barrier against water piercing into the house. The rows of roofing paper are tacked or stapled in place as they are overlapped upward toward a peak.
Eave sides and gable sides get an application of metal drip around the edging of the roof. The metal edge drip is nailed over ice guard or roofing paper.
Apply new valley flashing where applicable where the two roof planes meet. Valley flashing is usually nailed to the roofing deck, sealed with roofing caulk.
Starting at the eaves, apply tab shingles and work upward toward the peak. Roof vents are then installed as shingles progress toward the peak.
Around areas where leaking can occur, apply flashing. These places are usually the chimney, stack vents and skylights. It’s possible flashing installation is apart of the roofing installation as the rows of shingles progress upward on the roof deck.
A ridge vent installation is important, as it will help air circulation in the attic space, helping with exhausting hot air and preventing ice dams during winter. Its best installed on a new roof and not an old roof. If the ridge vent cannot be installed, another type of roof or gable vents should be installed to provide air circulation in the attic area.
Final cleanup and haul debris away. Inspect the installation by a professional and a building inspector must approve.
Common terminology used in the roofing business:
- Square: A unit of area. One square equals 100 square feet.
- Bundles: As shingles come in bundles, three or four bundles of shingles usually cover a square of roofing area.