Not all repair projects are a top priority, but roof issues cannot be put off for a later time — especially if it’s an issue with leaking. If you were to check your roof right now and see shingles that are missing, curled or cracked, you know you will have to take care of this problem soon before it costs you irreversible water damage.
To check for problem areas with your roof, not only check the shingles, but also check for cracks around skylights, chimneys, roof valleys and around the vents. If you see cracks, then it’s time to do some repairs to your roof. But before we get into the types of residential roofing materials available, let’s discuss the difference between the two major types of roofing: pitch roofing (or sloping roofing) and flat roofing.
Pitched Roof vs. Flat Roof
A pitched roof is a roof that has a highly-visible slope and a pitch of 4 and 12 or more. Flat roofs (often referred to as low sloped or low-pitched roofs) have a very little slope (often pitches of 3 and 12 and less) and are available in built-up, single-ply, torch down, modified bitumen and sprayed polyurethane foam designs.
Flat roofs are often used on rooms or buildings that are not a part of the traditional living space. For example, you can expect to see flat roofs on deck spaces (or other outdoor living spots) and garages.
Pitched roofs offer a lot when it comes to beauty and charm, but they also have their downside. They tend to be hard to check when looking for leaks because of the sloped design. On the other hand, flat roofs are easier to inspect for leaks, but they tend to need more repairing since drains often get clogged and create leaks. You will also need to make sure the material has a waterproof seal as a preventive measure for leaks. However, if you check the roof regularly, you won’t have any issues with leaks, which will eliminate the need for costly repairs.
Although flat roofs require more maintenance, they will save you on exterior maintenance (windows, decks and doors). Also, flat roofs have the benefit of being much cheaper than pitched roofs. You also get a large overhang (where the plane of the roof hangs out past the walls of the house) when you have a flat roof. The overhang helps protect the house from unwanted ultraviolet rays.
Example of roof pitches:
Types of Roofing Material
Pitch Roofing Materials
Asphalt shingles can be a single layer or have multiple layers (also known as laminated strip singles). Shingles that are multi-layered will contain the following:
- The weather-resistant base material is usually felt or glass fibre. It allows the roof to maintain its sturdiness.
- Felt shingles must have the ASTM standard D 225, and glass fibre shingles must meet the ASTM standard D 3462.
- Fillers (like asphalt)
- The surface layer of mineral granules that offers UV protection and helps with making the roof fire retardant.
Strip shingle, the most popular asphalt shingle material, is 12″x 36″, and has 3 (sometimes 4) tables. includes three or four exposed tabs.
These tabs can be one piece (also known as non-cut-out strip shingles), separated from each other or randomly arranged (also known as random tab strip shingles).
You don’t have to worry much about upkeep when you first install asphalt shingles. However, as time goes by, you may find yourself needing to repair some of the shingles that have started to suffer granule erosion, curling or cracking. They may also be subject to environmental damage from mould, algae, and fungus if in a shady or wooded location.
The name says it all. When you use fibre-cement shingles, you are using shingles made of cement with reinforced fibres. Consider these to be a substitute for slate, shakes, wood shingles and tiles. They will even look like the type of shingles they are substituting for, but that doesn’t mean they will function as well as the type of shingle it is substituting for.
Regardless of what type of shingle you are substituting fibre-cement shingles for, they must adhere to the ASTM C1225 standard that deals with non-asbestos fibre-cement roofing material.
Slate is a very thick but sturdy material that is all natural and waterproof.
The texture of the shingles depends on what type of rock it was taken from. So, some slates will be very rough and bumpy while others will have a smooth surface. The colour will be largely determined by how the actual rock material it was taken from reacts to weather exposure.
Slate comes in three categories:
- Standard: This type of slate is rough on the surface. The thickness of this type is typically between 3/16-in. and 1/4-in. The pieces will be of the same length.
- Standard Smooth: The same qualifications of the standard type except this one is smooth on the surface.
- Graduated (or Textural): The thickness and length of this slate will vary. This type of slate is the roughest of the three.
Regardless of the category, all types of slate must meet the ASTM C 406 standard for slate roofing material.
Wood Shakes and Shingles
Wood shakes and shingles are made of red cedar, redwood, pine and cypress.
Wood shakes come from logs split and reshaped into pieces. They are thicker than shingles on the butt end, and it can be split on one side or both to give the shakes texture. Wood shakes tend to offer more durability than wood shingles. They are easy to replace, and they will develop a greyish colour over time.
Unlike wood shakes, wood shingles will have the same thickness on both ends, and they will be saved on both sides. You can find them in both 18-inch (called Perfection) or 24-inch (called Royal) size. Like wood shakes, wood shingles are easy to replace, and they develop a greyish colour over time.
Metal Roof Systems
Metal roof systems come in two types: structural and architectural. Structural metal is primarily used for flat roofs because of its water-resistant nature and durability. It works well for flat roofs on commercial buildings with gaps between structural supports like factories. They are mechanically attached to the roof’s structure.
Architectural metal works well for roofs with a steep slope because of its water-shedding capabilities.
There are two classifications of architectural metal:
- Individual components: These work well as residential roofing materials for houses with a steep slope.
- Panels: These are large metallic sheets that come in five types:
- Shingle panel: These panels are die-formed and will resemble the appearance of tile, wood or slate shingles.
- Bermuda panel: These panels form horizontal lines on the roof slope because these continuous panels are laid perpendicular to the roof slope.
- Standard seam: The seams are joined above the panel flats.
- Flat seam: These panels are put on the roof like shingles.
- Batten seam: These are vertical leg panels that are placed between wooden batten strips and are capped off.
Decking or solid roof sheathing is necessary for this type of roofing to be applied.
Clay and Concrete Tiles
Tile roofing requires additional roof structure to handle the weight of the clay tiles which can be 4 times that of asphalt shingles. Tiles come in many colours, finishes and styles. You can also get different textures for them.
There are two main types of roofing tiles: Clay and Concrete.
- Clay Tiles: These tiles are made from moulded The sturdiness of the tiles will vary since they may not all be heated at the same temperature and for the same length of time. Clay tiles need to meet the ASTM C 1167 standards for clay roof tiles.
- Concrete Tiles: These tiles are made of Portland cement, sand and water. The ingredients are poured into a mould after being subjected to high pressure. The pieces are interlocking and are very durable. Concrete tiles are cheaper than clay tiles.
Concrete tiles (and clay tiles) can resemble wood shakes, and they can also look like slate, stone or clay tiles. Clay tile roofing can be as diverse as contemporary geometric shapes or traditional European villa style. However, most clay tiles will be barrel-shaped and red in colour. These are known as the Spanish tile design. The French tile design is flute-shaped.
When doing pitch roofing, make sure you get a professional opinion on what type of roofing materials will work best for a home that has a pitched roof. The answer should take into consideration the look you are going for, the type of protection needed and the type of weather resistance needed to thrive in your residential environment.
Flat Roofing Materials
Single-Ply Residential Roofing Materials
Single-ply roofing materials go by the technical names of elastomeric or plastomeric membrane. This membranous material is a popular choice when roofing commercial buildings. When applied on either a commercial or residential building, the sheets will be no more than 0.030 (30 ml) to 0.060 inches (60 ml) thick, and each sheet will be applied in a single layer. There are several kinds of single-ply roofing materials:
- EPDM (ethylene propylene diene monomer)
- PVC (polyvinyl chloride)
- Neoprene (polychloroprene):
- Chlorinated polyethylene or chlorosulfonated polyethylene sheets
- Polymer-modified bitumen
Single-ply roofing material is highly elastic and flexible because they are made of polymer or synthetic rubber. These characteristics also allow single-ply roofing material to withstand temperature changes better than built-up roofs (which will be discussed later).
Membrane roofs can be attached in different ways. If you have a roof structure, they can be secured with river rock ballast. You can also have them attached to the roof deck. The adhesive material is used to fasten EPDM and Neoprene roof seams, and PVC roof seams are welded together.
Modified Bitumen/Torch-Down Roof
Single-ply roofing material may be highly durable, but because it’s only one layer, it’s easy for them to get damaged from sharp objects and bumps. That’s why multi-layer material like modified bitumen is a good option for roofing material.
This type of roofing material was invented during the 1960s as an upgrade to built-up roofing (BUR). The layers will have polymer reinforced cap sheet layers. There are four methods you can use to attach modified bitumen to your roof. Each method used depends upon what specifications you have for your roof. The installation methods are:
- Hot Applied
- Torch Applied*
- Cold Applied
*Also known as ”Torch-down” roofing: This is a single layer membrane-style roofing material that is heat-activated by a torch during installation.
The polymer-reinforced cap sheet makes the material more flexible in cold environments. The most popular polymers used for residential roofing materials are atactic polypropylene (APP) and styrene butadiene styrene (SBS).
SBS gives the material a rubbery texture and is applied using a cold adhesive (or hot asphalt tar). Thermoplastic APP sheets are applied using the torch-down roofing method.
Built-Up Roof (BUR Roofing)
The built-up roofing (BUR) material is over a century old and was an excellent solution for solving the asphalt shingle problem for flat roofs. It is sometimes referred to as tar-and-gravel because of how it’s made.
Built-up roofing material is an asphalt containing felt material that is applied in multiple layers and covered with bitumen using a hot mop. Modern BUR techniques will alternate layers of bitumen with other reinforcing materials.
The asphalt (or coal tar) material blends with the bitumen to create a large membranous material that is applied with heat in multiple layers until it is between two- to four-ply thick.
To provide weather-resistance and UV protection, crushed stone is applied to the top layer of hot bitumen.
Because the material has a strong odour, and the process is very messy when it’s being installed, it is recommended the house not be occupied when this type of roofing material is being installed. Also, this project should be done by a roofing professional and not attempted by an inexperienced roofer.
Spray-On Roof Material (GPR Fibreglass)
GRP Fibreglass is a paint-on solution (often referred to as liquid roofing. It is great for flat roofs that are not standard sized or roofs that have an awkward shape. Although the material is lightweight, it is highly durable and can withstand a lot of foot traffic and collisions.
How to Calculate Roofing Materials Needed
You have to make sure that the type of roofing system you want can fit your budget. But before all this can be done, you need to know how much material will be used if you choose a certain type of material. To help with this, you can use this online roof tile amount calculator to determine how much material you will need to buy.
After you have an estimate of how much material you will need to buy for the roofing system suggested for your house, you can calculate the cost of the entire installation. To calculate flat roofing systems, keep in mind that installing PVC membrane costs roughly between €6.10 to €8.71 per square foot, and EPDM rubber costs between €3.50 and €6.10 per square foot. Modified Bitumen Estimated costs between €2.61 to €5.23 per square foot installed. BUR roofing material costs range from €4.36 to € 6.10 per square foot installed. TPO roofing material costs are approximately €4.36 to €7.41 per square foot installed.
You can also use this UK/Ireland Roofing Calculator to help with pitch roofing estimates!