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Rooftop Equipment Securement Guidelines
HIGHLY PROTECTED RISK (HPR) ASSET PROTECTION “STARTS ON THE ROOF”

Overview
The roof is a building’s most critical and yet most vulnerable asset. Whenthe wind begins to blow, all elements of the roof must perform uniformly
including equipment that is installed on the roof. Similar to how seatbelts
function in a car, well designed rooftop equipment securement will
prevent equipment movement up to the limits of the structure’s design.
When subjected to high winds, inadequately secured rooftop equipment
may be dislodged, resulting in severe damage to the roof cover andstructure making the building more vulnerable to the ongoing wind threat.
Exhaust fan with no base fasteners

PurposeThis guideline is intended to draw attention to typical rooftop
equipment installation practices and deficiencies. Despite close
attention being paid to windstorm resistance for roof structures androof covers, some rooftop equipment is commonly installed without
any means for securement other than weight. In addition, often
there is less rigorous control over the methods used to secure
equipment that is installed in between new construction or reroofing projects. If rooftop equipment is not well secured, it may
become detached leaving the roof and all of the assets within thefacility more vulnerable. From a risk assessment standpoint,
severe damage to a building’s roof can be a single point failuremode potential for the facility as a whole. Utilizing the approach
outlined in this technical resource will equip the user to address
rooftop equipment securement in both construction and retrofit
circumstances.
Split HVAC unit not secured to its curb

Rooftop Equipment Securement Guidelines
Rooftop Equipment Securement Best Practices
Tokio Marine America (TMA) HPR Property Loss Control recommends following Factory Mutual (FM) datasheets forbest protection against Natural Hazards. These windstorm guidelines adhere to the technical advice detailed in thereferenced documents. Whether considering new construction, major renovations, maintenance related roof
replacement or repairs or updating your risk management plan, follow the TMA HPR Loss Control “WIND” advice asa best practice.
Wherever your facility is located, all new important structures
should be designed to meet applicable standards

Investigate all existing important structures for conformance toappropriate standards



Necessary retrofit upgrades should be strategically consideredfollowing the advice of your Account Team

Decide in advance to meet these guidelines by inclusion incorporate design specifications
TMA HPR Loss Control Plan Review services areavailable to assist with your project

Equipment installed on the roof needs to be secured to the structure in a manner equivalent to or exceeding thestrength of the structure itself. Equipment could become dislodged and damage the roof cover or leave large holes
where the equipment was located. This may also cause a premature failure of the roof cover or structure during highwind exposure. Securing rooftop equipment protects the building, roof cover and its contents from unexpected
additional damage that would otherwise not occur if the equipment were adequately secured.
During construction or major re-roofing, plan to evaluate new and existing equipment securement methods using a
proven engineering method to meet the anticipated wind uplift forces. However, in lower wind speed zones (< 110mph) the prescriptive approach outlined in this document offers an alternative that is best applied for existing
equipment. Applying the best practices outlined in this document will help to assure that rooftop equipment will remain
secured to the structure during a storm.

Tokio Marine Management, Inc. does not represent, warrant, or guarantee the appropriateness, validity or accuracy of this information in every
situation. This information does not necessarily cover every
possible condition, protection, hazard, situation or exposure and is not warranted to comply with laws, regulations, codes or standards in every jurisdiction. This information is representative of reasonable
practices in the industry. However, you may wish to investigate whether these recommendations are applicable to your specific operations. Loss control is the responsibility of your management.
© 2020 Tokio Marine America, All Rights Reserved.

2|P a g eRooftop Equipment Securement Guidelines
Rooftop Equipment Securement - Prescriptive Approach
There are a variety of sizes and types of rooftop equipment typically found on the roof. Larger equipment is typicallymounted on steel framing that is merely an extension of the buildings structural framing. Other equipment suchas packaged HVAC units and most exhaust fans are mounted on curbs that outline the perimeter of a hole in theroof deck used to permit ductwork and utility penetration. Curb construction typically utilizes wood framing secured
to the roof structure and installation should follow referenced guidelines to ensure adequate resistance to wind
uplift. Lastly, some equipment may be installed on sleepers without any mechanical securement to the roof at all.
Ideally, all equipment should be secured mechanically to the building structure to ensure success of the entire
roof assembly.

Exhaust Fans on curbs – Secure the base to the curb using minimum No. 12 screws with neoprene
washers on all four sides spaced maximum 1 ft. on center or based upon referenced standards.

Fan Cowlings – The motor covers on top of many exhaust fans may become loose over time due to routine
usage. Loose cowlings should be secured using cable or strapping fastened utilizing minimum No. 12 screws.
The strapping should be run across the top of the cowling and secured on the opposing side of the fan base.
This method is recommended using two cables arranged perpendicular to each other in all cases when basewind speed is 110 mph or more.

Sleeper Mounted Equipment – Equipment such as split HVAC
condensing units, horizontally arranged exhaust fans, condensers,
ductwork and other equipment such as satellite dishes may often be
installed on wood, plastic or metal sleepers that elevate the equipment
above the roof surface. Sleepers are often not secured to the roof deckand is very vulnerable to wind uplift.

o The use of sleepers should beavoided for all new equipment
installations on existing roofs ornew construction.
o Re-roofing specifications
should indicate that existing
sleepers be replaced with curbs.
o Alternatively, this equipment
should be secured to properly
installed curbs that are secured tothe structure.

Well secured curb mounted exhaust fan;use two straps in high wind zones

Sleeper mounted equipment secured withiron rods via pitch pockets

Tokio Marine Management, Inc. does not represent, warrant, or guarantee the appropriateness, validity or accuracy of this information in every
situation. This information does not necessarily cover every
possible condition, protection, hazard, situation or exposure and is not warranted to comply with laws, regulations, codes or standards in every jurisdiction. This information is representative of reasonable
practices in the industry. However, you may wish to investigate whether these recommendations are applicable to your specific operations. Loss control is the responsibility of your management.
© 2020 Tokio Marine America, All Rights Reserved.

3|P a g eRooftop Equipment Securement GuidelinesoWhen re-roofing is not scheduled for the near future, consider
installing iron rods secured to the structure via pitch pockets.
Next, secure the equipment to the rods using rigid metal
brackets and/or cables. The equipment should be well secured
to the sleepers. NOTE: This method is anticipated to beeffective only for inland, lower wind speed locations until reroofing permits equipment to be reinstalled using curbs.

o Where existing equipment is installed on sleepers in coastal,high wind speed zone (i.e., > 110 mph) locations, curbs should
be retrofitted and the equipment reinstalled and secured to thecurbs.

Ductwork secured using brackets via pitch
pocketsPackaged HVAC Units – This common equipment is installed on curbs positioned over a large opening
in the roof where ductwork and utilities pass into the building. This equipment is typically installed without
mechanical securement to the structure but is typically larger and heavier. In some cases, roof mounted
ductwork or filter sections may be connected and installed unsecured tothe structure. Utilize engineered solutions as outlined in applicableguidelines to ensure adequate securement methods are prescribed. Thismethod is recommended for new locations where the base wind speed is> 120 mph or > 110 mph within 1 mile of the coast. However, in lower
wind speed locations, existing equipment may be secured by adding
cable ties and/or strapping. This will provide enhanced securement thatin combination with the weight of the equipment will be effective in theselower wind speed zones:o Metal strapping attached to the curbing on opposing sides of the unit
using two minimum # 12 screws on each side.
o Alternatively, install thick (¼ in.) angle iron with an eyelet in its topflange. Attach the angle iron using two minimum ¼ in. bolts or screws tothe curbing.
o Utilize minimum ¼ in. cable to connect the angle iron via the eyelet to
all rigging points of the unit, typically in all four corners. Additional cable
Packaged HVAC unit secured to curb using ties may be needed for larger, particularly long equipment.
angle iron & cable tieso In 90 mph, inland wind zones, two cable ties in opposing corners may
be considered when equipment is protected such as behind a substantial
parapet wall.

Tokio Marine Management, Inc. does not represent, warrant, or guarantee the appropriateness, validity or accuracy of this information in every
situation. This information does not necessarily cover every
possible condition, protection, hazard, situation or exposure and is not warranted to comply with laws, regulations, codes or standards in every jurisdiction. This information is representative of reasonable
practices in the industry. However, you may wish to investigate whether these recommendations are applicable to your specific operations. Loss control is the responsibility of your management.
© 2020 Tokio Marine America, All Rights Reserved.

4|P a g eRooftop Equipment Securement Guidelines
Equipment mounted to steel framing – Thisequipment is commonly secured using beam clamps,welding, bolts or screws. Unlike packaged HVAC units
on curbs, which are typically unsecured, equipment
mounted on steel framing is typically secured to theframing. The most common error is using inadequately
sized screws or bolts or installing equipment that is not
rated for the applicable wind zone. Another common
pitfall is not replacing rusted or broken fasteners astime passes. Use larger bolts (½ - 1 in.) for larger
equipment and check or replace them periodically.
Even larger, heavier equipment may be blown off the roof whensecurement is deficient.

Summary of the risk
The risk of damage to your facility during a windstorm is significant and may result from many factors. One of the mostcommonly overlooked factors is securement of rooftop equipment. When rooftop equipment securement is not asstrong as the roof or roof cover, the equipment can become dislodged during the worst part of the storm. The ensuingdamage to the roof cover and building may result in business interruption, and damage equipment and inventory. To
protect your facility, begin outside on the roof with a windstorm risk engineering assessment. Then, take the necessary
steps during new construction, re-roofing and on a retrofit basis to ensure the facility is well protected when naturestrikes.

Reference Documents
FM Data Sheet 1-28 “Wind Design”
FM Data Sheet 1-15 “Roof Mounted Solar PV Panels”
FM Data Sheet 1-32 “Inspection and Maintenance of Roof Assemblies”
FEMA Document “Attachment of Rooftop Equipment in High-Wind Regions”

A service of the Tokio Marine America Loss Control Department.
TMM is committed to the highest customer trust.
We exist to deliver ANSHIN (safety, security and peace of mind) to our customers by providing the highest quality services.
This information is provided solely as a client service. Tokio Marine Management, Inc. does not represent, warrant, or guarantee the appropriateness, validity or accuracy of this information in every situation.
This information does not necessarily cover every possible condition, protection, hazard, situation or exposure and is not warranted to comply with laws, regulations, codes or standards in every jurisdiction.
This information is representative of reasonable practices in the industry. However, you may wish to investigate whether these recommendations are applicable to your specific operations. Loss control is theresponsibility of your management. | © 2020 Tokio Marine America, All Rights Reserved.
Tokio Marine America (TMA) is the marketing name for Tokio Marine America Insurance Company (TMAIC), Trans Pacific Insurance Company (TPI), and TNUS Insurance Company (TNUS).

Revised 4/28/2021