|After you call three to four local roofing companies, the real work of sorting through the confusion starts, mainly trying to figure out why all the roof replacement estimates are priced so differently? There are many factors that affect the decision-making process for selecting your roofing contractor, such as reputation, license and insurance. However, the scope of work, materials used, bid details and cost to complete the project are, ultimately, the most important factors.
How does a roofing company price a new roof? What are the variables to consider? Here are the top nine factors that will affect the price of your roof estimate:
- Roof Size. Roofers will take an accurate roof measurement based on square meterage.
- Roof Pitch or Slope. The roof’s pitch is important as a very steep roof, typically anything more than about 30° is generally considered not walkable and requires greater scaffolding and labour to complete the roof safely.
- Complexity of the Roof. One of the simplest roofs to install is a duo-pitched gable-to-gable roof, which involves two roofing planes, two eaves, one ridge and four verges. More complex roofs may be at different levels and have dormer windows, chimneys and extensions, which will likely introduce hips, valleys, mono-ridges, abutments, bonding gutters, raking cuts and leadwork. These features are generally labour intensive and they will add to the cost.
- Type of Roof Being Stripped. For the most part, roof stripping is determined by the time it takes to remove the material (ie, the labour cost) and the cost of waste disposal (ie, skip and tip charges), which is typically determined by the weight of the material, but this may be increased many fold if the materials are hazardous (eg, asbestos).
- Type of Roofing Surface Being Installed. There are significant differences between the various types of roofing materials available (eg, natural slates, fibre cement slates, clay tiles, concrete tiles, metal sheeting, single ply, fibreglass) and the type and style of the products selected will directly affect the aesthetic design, weight, durability and longevity of the new roof, and of course the cost you pay.
- Roofing System Components Being Installed. Most people think of their new roof simply as the slate or tile which is to be applied, but there is much more to waterproofing your roof over the long-term. The type of underlay, ventilation and insulation being installed, and even the types of fixings used, all carry different levels of performance and longevity, and thus affect the price.
- Contractor’s Access to the roof. Difficult access will require additional equipment and labour to set up the scaffolding, strip-off the old roof, load the new roof and complete the installation. Conversely, the easier the access, the less time and material needed to complete the job.
- Type of Roof Warranty. There is a significant difference between a standard roofing warranty, where the roofing contractor alone guarantees the labour and workmanship of the project, versus an extended warranty that is backed either by the manufacturer or through insurance. An extended warranty typically requires additional steps, materials and inspections, together with a fee that is charged to back and support the roofing contractor’s labour and workmanship.
- Extra Details. Finally, there are preparation and finishing details that affect the cost of the job. For example, the installation of sun tunnels and skylights, cutting around flues and soil vents, fitting cloaked verges and ridge finials, removing and refixing TV and satellite aerials, and replacing guttering. These will all affect the final cost you pay.