Title: Objective
1(No Transcript)
2Objective
- Design a Roofing Solution for the Mountain and
Snow Areas that will - Save Money
- Create a Safe Environment
- Promote Efficiency
3Americas Snow Solutions
- Design around the Snow
- Use metal to shed the snow
- Use Dormers to protect specific locations (like
the front door) from falling ice and snow
4The Goal of a Metal RoofShed the Snow
5Do Metal Roofs Solve the Snow and Ice Problem?
- Building does not have to sustain weight of the
snow - Reduced chance of ice dams
- Leak potential from ponding water reduced
6There is One Problem
How do you get into the house?
7FACT
Using Metal Roofs to Shed Snow Can Cause Serious
Problems!
8Damage to Dormers
9Damage to Paneling and Penetrations
10Damage to Flat Seam Metal Roofing
11Gutter Damage
12Dormers Can be Torn Off
13Lower roofs can be damaged by snow falling from
upper roof
14People and property below can be in danger
15Metal Roof Failures
16Metal Roof Failures
17Metal Roof Failures
18Another Metal Roof Failure
DANGER FALLING SNOW AND ICE FROM
ROOF CAUTION DO NOT PARKTOO CLOSE TO THE
BUILDING
(Many more photos available upon request!)
19What are the disadvantages to shedding the snow?
- Snow builds up on the ground and must be removed
- Hazard to people and property (lawsuits waiting
to happen) - Causes damage to roof
- Building is already required by code to hold the
snow load - Less design freedom
- Loss of snow as an insulator
- Ice dams occur with low slopes and large overhangs
20Do other Roofing Materials Work Any Better?
- Metal?
- Asphalt Shingle?
- Tile?
- Wood Shake?
21Asphalt Shingles Damaged by Sliding Ice and Snow
22Tile Roof Valley Damage from Sliding Snow and Ice
23Wood Shake RoofSnow and Ice Broke Off Deck
Railing
24Wood Shake RoofSnow and Ice movement damaged
valley and rake
25All Roof Types Have Problems!
Asphalt
Metal
Tile
Shake
26What else can we try?
Do These Work?
27Designing Around the Snow Using Dormers
- Multi Level Condo in Mountain Area
- Asphalt Shingle Roof with a Slope of 4/12
Dormers hold the snow and ice in place minimizing
the possible locations for snow
and ice to fall
28Dormer Failures
Dormers have isolated the areas to which snow is
shed but huge icicles hang about with tremendous
damage potential.
This dormer protected the walkway but the sliding
snow and ice damaged the metal paneling, which
will likely need to be replaced each year.
29Damage to the Valley of a Dormer
30Using Dormers to Design Around the Snow
- Points of Potential Damage
31Using Dormers to Design Around the Snow
- Points of Potential Damage X10
32What else can we try?
- Snow Retention
- Dormers
- Snow Brackets
- Snow Fences
Do These Work?
33Snow Brackets/Snow Fences
34Do Snow Brackets Work?
Damage even with Snow Brackets ¼ plate steel
brackets
Damage to Eaves from sliding snow ice
35Snow Bracket Failure on a Slate Roof
36Snow Bracket and Snow Fence Failures on Asphalt
Shingle Roofs
37Snow Fences used alone were not able to prevent
damage
38Damaged Snow Fences
Sliding Ice and Snow was too much for Snow Fences
to withstand
39Plastic Roof Brackets
Why didnt these work?
40Metal Roof Brackets
These brackets have been flattened by snow and
ice movement
41Metal Roofs are designed to shed snow, not hold it
- Panels will expand and contract
- Panel is attached at only one location at eave or
ridge - Adhesive on panels won't work
- Snow Brackets installed through panels into
sheathing can cause metal to slot, screws to
break and "oil canning" of metal
42Snow Brackets and Snow Fences Didnt Solve the
Problem!
- Didnt stop moving ice and snow
- Didnt prevent damage to the roof
- Didnt prevent damage to the people below
43What about Ice Dams?
Fort Drum, NY
Utah
44What Causes Ice Dams?
- Heat Loss from Building
- Sun Melting Snow, then water freezing in shaded
or eave areas
Cold
Hot
45American Solution to Ice Dams
- Make a waterproof liner so that ponding water
doesn't enter building - Ice and water shield works like a bathtub liner
- Does Ice and Water Shield stop Ice Dams? NO!
46When should Ice and Water Shield be used?
- Use on eaves, rakes and valleys
- Be aware that condensation will be a problem when
using ice and water shield on 100 of the roof
when attics are not vented
47When Should Heat Cable be used?
- Heat Exhaust Fan
- Some Shaded North Exposure
- Heat Cable should always be hidden
48How Heat Cable works
- Heat tape to create tunnels through ice to allow
water to exit roof - Heats exterior of building to alleviate a problem
- Question Why are we heating the outdoors
especially with the high energy costs we are
currently experiencing?
49(No Transcript)
50Theres Got to be a Better Way!
- What does the rest of the world do?
51Europes Snow Solution
Low Lands
Mountains
Low Lands-They dont use an underlayment and they
use an average 12/12 slope
Mountains-They want to hold the snow on the roofs
so they make the slope less steep
Note This is exactly the opposite of US and
Canada
52How Does Europe Overcome these Problems?
53European Solution to Ice Dams and Condensation
Concerns
- Vent below Roof Deck. Why?
- To lower temperature so that snow does not melt
and re-freeze at the eaves - To remove vapor from attic space to stop
condensation
Cold
Heat
54Ventilation removes vapor from structure
Dew Point
Cold
Vapor
Underlayment on roof sheathing becomes a vapor
barrier about dew point. This creates the
potential for condensation back into the
building. Ventilation removes vapor from the
structure, preventing condensation which could
drip moisture into the building.
55European Solution to Ice Dams and Vapor Loss
- Vent above Roof Deck. Why?
- The use of vertical battens extends the life of
the underlayment by eliminating ponding water and
dirt behind horizontal battens.
This is a 9 year old roof in Topeka Kansas.
Heres how you fix the problem forever.
56Question
- Why do some Cold Roof Systems not work?
57Problem 1
- Inadequate size of Intake Venting
Intake Vent
58Problem 2
59Problem 3
60Problem 4
- Insulation at plate line blocks air
61Problem 5
Gable vents act as an intake vent if you have
both eave and ridge vents. The gable vent pulls
snow into the attic.
62 Correct Ventilation in Sun Peak, Canada
Not Vented
Vented
These roofs are 100 yards apart!
63How Does Europe Overcome these Problems?
- Ice Dams
- Heavy Snow Load on the Roof
64 Should Snow Weight Really be a Concern?
- There are building requirements for the live load
in each building location. - Are building costs lowered by increasing the
slope? - How much are the building costs reduced by the
limited load deduction from shedding the snow? - Are the buildings Strong Enough?
- Yes, they were engineered to be that way.
65How Does Europe Overcome these Problems?
- Ice Dams
- Heavy Snow Load on the Roof
- Faulty Snow Retention
66What it takes to make Snow Brackets and Snow
Fences Work!
- Proper Engineering
- Bracket Itself
- Bracket to the roofing system (pullout)
67 Why Snow Brackets and Snow Fences Fail
- The most common reason They are not engineered
to the roof system. - Example The bracket is strong enough to hold
extreme weight but it pulls out from the roof
system because it was not attached to withstand
the amount of pressure its under.
68Engineering in Europe
Chart produced in Germany
69American Engineering (TRA)
70How Important is Engineering?
71What it takes to make Snow Brackets and Snow
Fences Work!
- Proper Engineering
- Bracket Itself
- Bracket to the roofing system (pullout)
- Proper Installation
- Bracket Layout
- Proper physical installation
72Designed Usage of Snow Brackets/Snow Fences
Snow Fence Designed to prevent avalanching snow
Snow Bracket Designed to hold snow in place to
prevent glacial movement
73Snow Brackets
Brackets should be spaced through the system from
eave to ridge in a staggered pattern.
Snow Bracket
Type A for Tile Roofs
74Snow Fences
As snow retention device to prevent avalanching
snow that is mounted to the roof in rows
beginning at the plate line and then repeating
again approximately every 20 feet from eave to
ridge based upon area snow load and roof
slope. Example Snow Fence Types
75What is the proper application of Snow Brackets
and Snow Fences?
German Alps
Brackets
Snow Fence
76Red Flags
- Beware if the person installing your Snow
Brackets/Snow Fences does not address the
following - Slope of Roof
- Snowload
- What is the bracket/fence attached to?
77Examples Good and Bad
78Examples Good and Bad
79Examples Good and Bad
80Proper Installation of Snow Brackets
These brackets have been engineered to the roof
SYSTEM for pullout and to withstand the weight of
the ice and snow.
81Proper installation of brackets on a metal roof
82Monier Cedar-Lite
83Bartile-Sundance, Utah
84Owens Corning, Miravistain Sundance, Utah
85Proper Installation of Snow Fences
These fences have been engineered to the roof
SYSTEM for pullout and to withstand the weight of
the ice and snow.
86European Style Snow Fences and Brackets
Many European Snow Brackets and Fences are
actually part of the tile
87TRA brackets installed on left side. No brackets
on right side.
88Under the eave snow and ice is extending beyond
the roof threatening damage to the roof and
people below.
89Extended snow and ice has broken off at eave in
area of no Snow Bracket
90Snow Brackets and Snow Fences What are their
benefits?
- Stops damage to roof from sliding snow and ice
- Allows safe access all around the building
- Even distribution of the weight from snow and ice
- Even snow melt-off
- Creates an insulation blanket
91The European System revolves around 3 points
- Take any vapor that has escaped into the roof
cavity above the insulation and pull the vapor
out through the ridge with venting air - Stop ice dams by making roof temperature equal
- Hold snow on the roof with snow retention
brackets to create an insulated blanket
92What makes a successful roof?
- Proper Ventilation
- No ice dams or icicles
- No leaks from ice dams
- No condensation concerns
- Proper (Engineered) Snow Retention
- Reduced snow removal
- Design Freedom
- No damage to valleys, eaves, rakes or
penetrations - Insulation Blanket energy saver
- People and property are safer
93Review Climate Types and Roof Details!
For consultation to determine cold/hot/vapor
areas of your roof and to design a snow retention
system in a CSI format, contact
TRA Snowbrackets at 801.756.8666 or
info_at_trasnowbrackets.com