Winter Concerns: Ice Damming, De-Icing Chemicals

Presented by: John T. Stevens, ICS, RS, CGP

Vice President and General Manager, Kipcon Inc.

jstevens@kipcon.com

(732) 220-0200

What I Will Be Talking About…

What is Ice Damming

Symptoms

Results

Causes

Aggravating Factors

Short Term Solutions

Long Term Solutions

What Is Ice Damming?

When a roof is covered

with snow and the outside

temperatures remain at or

below freezing for an

extended period of time,

ice accumulates on the

roof (typically at the eaves

but also in other locations)

and forms “dams.”

Then, when the snow

melts, the water backs up

behind the ice “dams,”

which can penetrate under

the roof shingles and into

the interior of the building.

Symptoms of Ice Damming

Symptoms

Typical Pattern of Snow Melt

on Roof

Icicles Hanging from Eaves

Gutters Clogged with Ice

Ice Damming Symptoms: Typical Pattern of Snow Melt on Roof

Snowmelt refreezes at eaves

Glacier like

Roof shingles and deck can be damaged by

refreezing

Ice Damming Symptoms: Typical Pattern of Snow Melt on Roof

Ice Damming Symptoms: Typical Pattern of Snow Melt on Roof

Ice Damming Symptoms: Typical Pattern of Snow Melt on Roof

Ice Damming Symptoms: Icicles Hanging from Eaves

Indication of

effectiveness of attic

insulation

Icicles are not,

themselves, a problem

Ice Damming Symptoms: Gutters Clogged with Ice

This contributes to

overload of ice at eaves

Interferes with drainage

and aggravates problem.

However, this is not the

cause

Ice Damming Results

Roof/Shingle Damage

Water Penetration into the

Building

Ice Damming Results: Roof/Shingle Damage

Ice Damming Results: Water Penetration Into Building

Results from ice dams

at eaves blocking runoff

of snowmelt

Can penetrate into many

areas (wall cavities;

rafters/trusses, plates,

etc.)

Ice Damming Results: Water Penetration Into Building

The problem is difficult to see until water intrusion into the interior

spaces occurs.

What Causes Ice Damming

Process of Ice Dam Development

Snow/Ice Build Up on Roof

Extended Period of Subfreezing

Temperatures

What Causes Ice Damming: Process of Ice Dam Development

1. Snow fall covers the roof (snow blanket is a good insulator)

2. Warm attic air melts snow

3. Most melting occurs at the ridge because the warmest air is at the

ridge and coldest is at the eaves

4. Snow melt runoff flows under the insulating blanket of snow cover

and refreezes at the eaves, forming dams of ice

5. As more water emerges from the snow blanket, it is blocked by the

ice dams. Water pools on roof and backs up under shingles and

roof deck

What Causes Ice Damming: Process of Ice Dam Development

What Causes Ice Damming: Snow Buildup On Roof

As little as 1”-2” of snow can

cause problems

The deeper the snow, the

more inevitable that ice

damming will occur

Wind blown snow can lessen

or worsen the ice damming

conditions by clearing or

adding snow to different roof

areas

What Causes Ice Damming: Subfreezing Temperatures

Usually takes a minimum of 3-

4 days to develop ice dams

The colder the temperature,

the worse the problem

What Causes Ice Damming: Aggravating Factors

Inadequate Attic Ventilation

Improper Attic Insulation

Poor Construction

Techniques

What Causes Ice Damming: Inadequate Attic Ventilation

The minimum required

ventilation is not sufficient to

prevent ice dams

You can never have too

much ventilation

Ventilation must be looked at

together with improper

insulation

What Causes Ice Damming: Improper Attic Insulation

Typically not enough is installed

(Norm = 6”; Need 10”-12”)

Not installed properly (has

voids, thin spots, missing, etc.)

Uninsulated flue and dryer vent

pipes. Insulation should not

block the soffit vents

Insulation must be looked at

together with inadequate

ventilation

What Causes Ice Damming: Poor Construction Techniques

Not properly securing

insulation blocking vents

Careless placement of

insulation

Lack of attention paid to the

detail of soffits

Short-Term Ice Dam Solutions

Removal of Snow/Ice from Roof

Removal of Gutters

Use of Snow Melt Devices

Use of Snow Breaker

Short-Term Ice Dam Solutions: Removal of Snow/Ice from Roof

Total removal is only effective way of

prevention in a “WARM” house

Partial removal only causes secondary ice

dams to form higher on roof

Removal can cause damage to the

shingles from the tools used and people

walking on the brittle shingles

Going on snow/ice covered roof is

DANGEROUS!!!

Heat cables or tapes accomplish the same

thing as partial removal

Short-Term Ice Dam Solutions: Removal of Gutters

May provide temporary

relief by allowing better

drainage of snow melt

runoff. However, ice dams

still occur on roofs without

gutters

Short-Term Ice Dam Solutions: Use of Snow Melt Devices

Heat cable; different types of

gutters and/or gutter covers, etc.

Many items on the market which

may or may not provide some

level of relief but they only

address the symptoms not the

causes.

Short-Term Ice Dam Solutions: Use of Ice Dam Breaker

1. Fill the leg of discarded pair of panty

hose with a calcium chloride ice melter.

2. Lay the hose onto the roof so it crosses

the ice dam and overhangs the gutter. If

necessary, use a long-handled garden

rake or hoe to push it into position.

3. The calcium chloride will eventually

melt through the snow and ice and

create a channel for water to flow down

into the gutters or off the roof.

Long-Term Ice Dam Solutions:

Install Eave Flashing

Correct Inadequate Attic Ventilation

Ensure Insulation is Properly

Installed

Long-Term Ice Dam Solutions: Install Eave Flashing

Install Eave Flashing

Use membrane (Ice and Water

Shield or other manufacturer)

Membrane has adhesive

backing

that sticks to the roof and wall

sheathing.

It is self sealing and will not

allow

water penetration at fasteners.

Does not address causes; only

prevents water intrusion into

interior space of home.

Long-Term Ice Dam Solutions: Correct Attic and Ventilation

Insulation

Both components must be increased to

obtain a “Cold Roof”

Ventilation must allow for large scale air

movement to quickly get rid of warm air

Insulation must be thicker and more

carefully installed in order to keep heat

loss into the attic to a minimum

Heat generating penetrations into the attic

(flue pipes, dryer vents, etc.) must be

insulated

Special consideration must be given to the

plateline area to make sure it is both well

ventilated and well insulated

Long-Term Ice Dam Solutions: Typical Pattern of Snowmelt on Roof

What I Will Be Talking About

Types of De-icing Chemicals

Application of De-icers

Application of De-Icers

Clear snow prior to application

Apply de-icer in a thin, even layer

Protection of Surfaces

Use chemicals sparingly

Do not use Magnesium in any form

Do not use any de-icer on concrete less than 12

months old

Avoid spreading on plants and lawn

Protection of People and Pets

Keep chemicals away from children and pets

Limit pet’s exposure (wipe paws)

And Now the Short Commercial

Kipcon…

Decades of Experience Reserve Studies

Transition Studies

Value Engineering

Energy Audits

Building Envelope

Analysis and Design

Site Analysis and Design

Rebate Analysis

Specifications, Bidding and Contract Administration

Siding

Drainage

Roofing

Pavement

Restoration

Thank You!

Any Questions?? John Stevens, ICS, RS, CGP

Vice President & General Manager, Kipcon Inc.

jstevens@kipcon.com

(732) 220-0200

Kipcon Headquarters:

Kipcon Inc. New Jersey

Kipcon Regional Offices:

Kipcon Pennsylvania Fort Washington, Pennsylvania

Kipcon New England Boston, Massachusetts

Kipcon DC Alexandria, Virginia

Kipcon Great Lakes Chicago, Illinois

Kipcon Texas Sugar Land, Texas

Kipcon Inc.

800-828-4118

www.kipcon.com