Thanks to advances in technology and design, exterior doors can be made from a number of different materials. Generally all these materials offer the same design and configuration possibilities. Each material has its strengths and weaknesses and it is important to understand that good quality exterior doors can be made using any of these materials. What is paramount is good energy efficient design.
Wood exterior doors are desirable for their natural beauty, good insulating value and structural strength. They are widely available in a number of different woods ranging from pine, oak, cedar, mahogany and walnut. They do however require significant protection from the elements as well as regular maintenance. Manufacturers are required to treat wood with a preservative to help prevent rottingbut ongoing maintenance is the only way to ensure that your wood exterior door lasts and performs.
Is not the thermal performance of a wood inferior to the others? Is the wood door referred to here solid slab or stile and rail?
Steel exterior doors are actually made from a combination of materials. The interior structural components (rails and stiles) are often wood, the inner core is filled with insulating foam and the outer skin is made of galvanized steel. The inner wood structure gives it stability and strength. The foam core provides good insulation and the steel skins are durable, resistant to warping or rotting and require little maintenance.
Steel exterior doors can be painted any number of colours. They are also available with pre-finished PVC coatings that simulate a wood-grain finish.
Fibreglass exterior doors are constructed in the same fashion as steel exterior doors with wood stiles and rails and an inner core of injected foam. The outer skin is fibreglass. Fibreglass is very strong and durable. In addition to a flat painted surface, fibreglass can also be embossed to give it the texture and appearance of wood.
Vinyl exterior doors employ a multi-chambered vinyl structure for both the frames and panels (sashes) utilizing a steel, aluminum or wood re-enforcement to add strength and prevent distortion. Vinyl doors are good thermal insulators because of their multi-chambered designs and offer good thermal performance ratings. Vinyl is a very durable material and is resistant to extreme weather conditions. It is also very resistant to breakage and provides good protection against forced entry through the door. Vinyl doors will not rust, dent, or scratch, and require no special maintenance.