Foundations of Real Estate Management

BOMA International

Module 4: Building Operations II

Roofing Systems

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Objectives

List the components of a roofing system Describe the difference between built-up roofs,

modified bitumen roofs, and single-ply roofs

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Roofing Systems

Out of sight…out of mind

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Roofing Systems

Long-term fixed asset Use life cycle cost analysis

to determine best roof system for your application Goal: Longest roof system

life with lowest life cycle cost

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Why Do Roofing Systems Fail?

1. End of the roof’s useful life2. Inadequate maintenance3. Poor or improper design4. Poor or substandard installation5. Faulty materials

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Roofing Components

Decking (deck) Concrete or

corrugated steel panels

Insulation

Roofing materials

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Roofing Systems

Flat roofs Not really “flat” –

there is some degree of pitch

Usually pitches to front or back of property

Sometimes pitches to the center

Pitched roofs

Drains and gutters

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Roofing Systems

Inspect roofs for ponding Increases chance of leaks Adds significant amount of weight

Keep the insulation dry

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Common Roofing Systems

Built-up roofs Most expensive installation cost

Modified bitumen roofs Moderately expensive installation cost

Single-ply membrane roofs Least expensive installation cost

All roof systems should have walk paths to prevent damage

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Built-Up Roofs

Alternating layers Roofing ply sheets (felt) Asphalt or coal tar pitch

Usually 3-4 layers Final layer is either

topped with gravel or is smooth (top sheet)

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Built-Up Roofs

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Modified Bitumen Roofs

Bitumen Residual material after crude oil is

refined (“the bottom of the barrel”) Instead of ply sheets, system uses

thermoplastic or elastomeric coating materials and bitumen

Usually 2 layers – base sheet/top sheet

Fire hazard – fire watch for 60 minutes after work has concluded

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Modified Bitumen Roofs

Applied with hot asphalt, a propane torch, or cold asphaltic adhesive

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Modified Bitumen Roofs

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Single-Ply Membrane Roofs

Made up of a single ply of roofing material

Three main types: EPDM (ethylene propylene diene monomer)

Rubber PVC (polyvinyl chloride)

Vinyl TPO (thermoplastic olefin)

Plastic

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Single-Ply Membrane Roofs Adhered to the roof:

Ballasted (stones) Mechanically attached

(fasteners) Fully adhered (adhesives)

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Single-Ply Membrane Roofs

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Single-Ply MembraneBallasted roof system

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Single-Ply Membrane

Mechanically attached roof system

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Single-Ply MembraneFully attached roof system

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Single-Ply Membrane Seams

EPDM Seams are sealed and need routine

maintenance PVC and TPO

Seams are heat welded together

Can be manufactured in white Does not reduce cooling costs

Upper floor HVAC system is insulated Does reduce heat island effect in urban

environments

Foundations of Real Estate ManagementModule 4: Building Operations II

TMEPDM Seam Management

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Roof Maintenance Best Practices

Semiannual roof inspections Equipment installations on roof and roof

penetrations should always be supervised by roofer holding warranty

Remove leaves, plant material, and trash on regular basis

Inspect drains and ensure drains work properly

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Roof Maintenance

Grass growing on the roofThis is not a green roof!

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Roof Maintenance

Roof drain clogged with debris

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Roof Maintenance

Remove debris. Better yet – don’t let it accumulate in the

first place!

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Roof Warranty Usually 10 to 25 years Understand warranty requirements Roof inspections and preventive

maintenance are usually required Keep copies of all documentation! Make sure you use vendors certified and

approved by manufacturer

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Green Roofs Partially or totally covered with vegetation Advantages

Amenities space Reduce heating and cooling costs Reduce “heat island effect” Increase lifespan of the roof Reduce storm water runoff Filter pollutants and CO

Foundations of Real Estate ManagementModule 4: Building Operations II

TM

Green Roofs