How Much will it cost to replace my roof?

Perspectives
A Quarterly Information Source from Benchmark, Inc.
Volume 55 February 2006

How much will it cost to replace my roof?

by Chuck Shellhart

We are often asked what it will cost to replace a roof, or what should be budgeted for future replacement needs. There is no easy answer; numerous factors play a role in determining the cost of a new roof.

The following factors impact the cost of a roof replacement project, and should always be considered when budgeting for a replacement project.

Design

· What will the roof be used for?

· What is the amount of foot traffic?

· What is expected out of the roof?

· Is energy savings a consideration?

· Is a vapor retarder required?

· Is an air barrier required?

· What type of environment will the roof be subjected to?

· What type of sheet metal will be incorporated into the project (stainless steel, prefinished metal, galvanized steel, etc.)

· What is the anticipated design life? 10, 15 or 20 years?

· Is deck repair / replacement necessary?

· Does insurance play a role in the type of roof system installed?

· What is the warranty requirement? 10, 15 20 years (labor & material or system warranty, which would include all components provided by the material manufacturer).

Material Cost

· Type of roofing membrane - single-ply, modified bitumen, built-up, metal, spray applied polyurethane foam, etc.

· Is tapered insulation required?

· Type of insulation - polyisocyanurate, expanded polystyrene, extruded polystyrene, fiberboard, perlite, etc.

· Is cover board required?

· Are the roofing components mechanically attached, adhered or loose laid?

· What is the sheet metal type?

· Is deck replacement necessary?

· What type of warranty is required?

Labor Cost

· The amount of penetrations going through the roof or obstructions above the roof (such as cable trays, above roof piping, etc.) that may impede the production of the roofing contractor should be considered.

· Does the existing roof need to be removed, or can it be recovered?

· Is the roofing project a one to two story facility with good access in an industrial park, or is it a high-rise building in a downtown location?

Substrate Condition

· Deteriorated deck (steel, wood, Tectum, gypsum)

· Crushed / damaged insulation (recover project)

· Electrical conduit attached to the bottom side of the roof deck (if mechanical attachment of the roofing components is specified, the contractor will need to identify the location of the conduit).

Cost Drivers

Owner induced restrictions on the roofing contractor can impact the cost of the roofing project.

· Access to the roof - is there direct access from the ground to the roof? Or does the contractor need to traverse over adjacent roof areas to gain access?

· Is the ground staging area (material storage) close to the roof access point?

· Is interior protection required or can product be temporarily moved from within the area being worked?

· Can the roofing project be completed within normal work hours or does the project need to be completed during off hours or on weekends / holidays?

· Time of year - When contractors are busy, they raise prices. When they are hungry for work, they lower prices. Basic supply and demand. The best pricing from contractors usually occurs when they bid work in the winter for early spring; prices are often 10% to 20% lower.

Determining (estimating) a budget can be difficult and at best a guess. Many factors (tangible and intangible) have an impact on the cost of a roofing project. The more defined the scope of work, the less likely change orders will occur during the project.