Roofing and Building Center

Considering a Flat Roof

Posted on December 4, 2009 by Samuel Cheeseman ----- Advertisement

Flat Roof Solutions

The question of whether you should choose pitched or flat roofing for your home is not a new one. Both varieties of roof have their advantages over the other and it is important to weigh up the strengths and weaknesses of each. A flat roof design is one that is horizontal or very slightly inclined. This immediately poses problems in most environments because any rain water which lands on the roof is given little chance to drain off. Pools of water will often form and gradually penetrate the surface of the roof. This is particularly true when using some of the original flat roofing materials such as gravel or tar because they do not allow water to flow over them very easily. These materials also have a tendency to sag over time which will affect the angle of the roof and cause further pooling of water. The location of your home and your local weather conditions should be given serious consideration when deciding if you wish to install a flat roof. If you live in an area which typically experiences high levels of annual rainfall then flat roof house problems due to climate will not be uncommon. Frequent or heavy snow fall can also pose similar problems for these roofs.

It is important to think about initial flat roof construction costs, the cost of maintenance and also what the life of a flat roof if likely to be. Although the construction may be cheaper during the building stages you are likely going to end up paying considerably more over a period of time to cover flat roof repair. These kinds of roofs are generally much more vulnerable to damage than a typical pitched roof that will cost more to install. You may want to speak to other homeowners in your area in order to get some idea whether flat roof repairs are going to become a large expense after installation. You may also want to think about the security implications of choosing a flat roof for your home. They will tend to be less secure than a pitched roof partly due to their shape which means the chances of a burglary occurring are likely to increase.

Flat Roofing Options

There are many kinds of flat roof materials currently available. Here are some of the most commonly used.

A Coal Tar roof is produced using waste products from industrial processes that use coal in large quantities such as in the manufacturing of many kinds of metals. The material is waterproof, has a long life expectancy and with care will last well over half a century. Before using coal tar you must be sure that the roof will actually be flat or will have only a very small incline. You must also be familiar with the safety procedures necessary when dealing with this material as it produces hazardous fumes.

Many rubber based roofing materials such as Hypalon and Turbo Seal are also used in the construction of flat roofs. Perhaps the most widely used due to a good supply and its relative ease of installation compared to other products is EPDM (Ethylene Propylene Diene Monomer). EPDM can last up to 50 years depending on the method of installation used.

Asphalt is another material commonly used in flat roof construction. It is usually a waste product of processes used in the oil industries. Asphalt is classified as either type one, two, three or four with type one being used on perfectly flat roofs and type four being suitable for roofs with the steepest incline. An asphalt BUR (Built up roof) is currently the most widely used flat roof design. Many layers are used which provide effective waterproofing with gravel commonly being used as the roof surface. After a number of years the roofing material can begin to degrade which will cause cracks to appear. This is a common problem with asphalt flat roofing and is likely to lead to leaks if no repair work is carried out. Modifiers can be added to asphalt during the production process in order to improve its performance. APP (attactic polypropylene) and SBS (styrene-butadiene-styrene) are the most widely used modifiers and will help reduce the effects of ageing as well as improving the overall quality of the roofing material.

Cold liquid membranes are modern flat roofing materials produced using glass fibre, polyester and polyurethane. They have a major advantage over other materials as no large quantities of heat are required in production. Many other materials are also used in flat roof construction such as felt and many and many types of plastic. PVC flat roofing supplies made from materials similar to those used in the production of fascias, soffits and windows are now fairly common.

Strengths of Flat Roofing

Although there are many pitfalls to using flat roofs they do have some value. They ensure that all areas both above and below the roof can be used effectively. Pitched roofs restrict the usage of space under the roof itself and do not allow the roof to be used for many purposes due to the shape. A flat roof will allow rooms to be in place directly under it without the loss of usage in any areas. The roof itself can also be used for many purposes. Roof gardens or terraces can be created as long as the roof is well constructed and has been prepared to support extra weight. Solar panels can also be fitted effectively to a flat roof.

Maintenance

As with any kind of roof the life expectancy of flat roof systems can be increased considerably using periodic preventative maintenance. Many built up roofs can last up to 30 years especially those constructed using the more traditional tar materials. Roofing systems produced from some of the new cold applied liquid membranes can last even longer and many have certifications stating that you can expect a 30 year lifetime. It will be sensible to carry out a full inspection of your flat roof every year as well as after any major storm and carry out repairs as necessary to prevent bigger problems occurring in the future. Be sure to check the drainage and watch out for any signs of flat roof rain damage.

The most basic maintenance required to reduce the need for flat roof repair is to ensure that any pooling water is removed promptly. The risk of leaks occurring increases as the water remains on the roof for greater lengths of time. Devices such as siphons, roof drains and vacuums are used to remove the water. Any imperfections such as blisters in your flat roofing should be repaired before they cause leaks to occur. This can sometimes be completed by the homeowner but professionals will need to be used to fix more serious delaminations. If there are many small blisters or leaks starting to appear then a roof coating can be applied. This will extend the lifetime of the roof and when installed will provide a seamless surface which will be water tight.

Temperature

Flat roofs will tend to absorb more sunlight on hotter days than a pitched roof will and at the same time make your home colder during the winter. A pitched roof will usually better protect your home from very high or low temperatures throughout the year. Flat roof coverings can help to control the temperature inside the building as some are designed to have high levels of solar reflectivity. This will mean they reflect sunlight very effectively and prevent much of it from being absorbed by the roof. Flat roof insulation will ensure that not too much heat is lost during the winter months.

For many homeowners the low initial cost of installing a flat roof rather than a pitched one will not be enough to outweigh the likely extra costs they will face in the future for flat roof repairs. You really must research the different roofing options carefully before deciding against the investment in a traditional pitched roof. Having said that the flat roof is a sensible option for a minority of households but it is up to you to ensure that you are part of this small group before installing one.

Here is a website where you can obtain more details about different Roofing options.