This document discusses ice dams, including what they are, what causes them, their consequences, and how to prevent them. Ice dams form when snow on a roof melts and refreezes at the edge, creating a dam. They are caused by indoor heat escaping through the roof and melting snow. This can lead to water damage in homes. Prevention methods include air sealing, insulation, and ventilation to reduce indoor heat loss. Myths like using slide sheets or raking snow are dispelled. The first step recommended is a free home energy assessment.

1. ICE DAMS
NEXT STEP LIVING

2. ICE DAMS
This mini-workshop  What are ice dams?
is presented by the
Green Needham  What causes ice dams?
Collaborative and
Next Step Living.  What are the consequences of ice dams?
 How are ice dams prevented?
 The role of air sealing
 The role of insulation
 The role of ventilation
 Myths about ice dams
 First step…

3. CAN ICE DAMS BE PREVENTED?
 There is no perfect solution
to prevent ice dams.
 With the proper
preparation, ice dams can
be reduced, and in some
cases eliminated entirely.
http://greenhomesamerica.files.wordpress.com

4. WHAT ARE ICE DAMS?

5. WHAT ARE ICE DAMS?
Home in Sudbury last winter. How can they be identified?
 Icicles hanging off of
an eave of a house
are the main indicator
of ice dams.
 The larger the icicle,
the larger the ice dam.

6. WHAT ARE ICE DAMS?
1. Indoor heat loss
through attic, cathedral
ceilings and transitions
between walls and the
roof.
2. Melting water flows
down the roof towards the
eave.
3. An ice dam is formed.
4. Water builds up
behind the dam and
seeps into your home.
www.aquaguideinc.com

7. WHAT CAUSES ICE DAMS?
www.homeperformancetechnologies.com

8. WHAT CAUSES ICE DAMS?
icedamprevention.org

9. WHAT ARE THE CONSEQUENCES…
 Water damage leads to…
 Mold/Mildew
 Indoor air quality problems
 Structural damage
 Electrical damage
 Physical danger of falling icicles
elliotwhittier.com capslove.files.wor thelivinggreensolution.com
dpress.com

10. PREVENTING ICE DAMS
www.homeperformancetechnologies.com

11. AIR SEALING
The Mass Save Home
Energy Services
Program rebates air
sealing.
• 100% rebated
• Thermadome
• Vapor barrier for
dirt crawl spaces

12. INSULATION
Rebated under the Mass Some Home
Energy Services Program
• 75% off – up to $2,000 - per year
• R-38 – 11 inches – of insulation
• Dense pack under floored attics

13. VENTILATION
Ventilation is
rebated as part
of the
weatherization
contract under
the Mass Save
Program.
-Vents
-Insulated bath fan
hoses

14. STRUCTURAL REALITY
 Due to the design of certain homes,
eliminating ice dams will be very
difficult.
 Cathedral ceilings
 Cape Cod homes are more
prone to ice damming due
to convective heat loss in
transitions and sloped
ceilings.
greenhomesamerica.files.wordpress.com

15. MYTHS ABOUT ICE DAMS
Myth: Ice dams can be prevented by
slide sheets and electric coils.
Fact: While both of these solutions
have been said to work
anecdotally, neither actually
address the real problem.
www.buildingscience.com www.buildingscience.com

16. MYTHS ABOUT ICE DAMS
 Myth: Ice dams are related to the
gutters.
Fact: Gutters do not necessarily cause
ice dams, although they can be severely
damaged by ice dams by extending the
frozen layer of ice beyond the eave of
the roof, putting excessive stress and weight
on the gutters.
www.icedamcompany.com

17. MYTHS ABOUT ICE DAMS
 Myth: Raking the snow off the roof is a
great way to prevent ice dams.
Fact: Raking the snow off of your roof
can be very dangerous and cause
significant damage to the shingles. If
you don’t have ice dams, the layer of
snow that builds up on the roof is
actually a great insulator.
http://bladeworkz.com

18. FIRST STEP…
Visit www.greenneedham.org to learn
more about energy efficiency and no-cost
Mass Save home energy assessments.