Living in Colorado affords a wide array of issues for homeowners. In the summer, there are hail storms and extreme heat that can be tough on property. On the contrary, the winters can be intensely cold with the potential for blizzards and high winds. These factors combined can wreak havoc on the structure of your home or business, especially for the roof.

Since we just had the first official day of winter this week, I thought it would be fitting to discuss how to prevent the potential problems with heavy rooftop snow loads.  Depending on the type of roof, the weight of snow can induce a disaster, which is the last thing you need in really cold weather. For example, a metal or flat roof can’t sustain as much snow load but steeper pitched roof lets the snow slide off.

In this article from HeatTrak Homeowners Blog, they discuss some of the potential winter concerns for property owners:

5 Winter Roof Damage Issues Homeowners Need to Know

Image from

4. Heavy Rooftop Snow Loads

Different roofs are designed to handle different weight loads, and if too much ice and snow accumulates on top of your house, the risk of roof collapse is very real. Wet snow is especially heavy, but large drifts of even lighter snow can exert significant pressures. Sometimes, poor roof drainage and/or poor construction can make the situation worse and lead to an over-stressed roof that begins to creak, leak, and cause ceiling sagging. This is a serious situation, so you should not delay in calling in the professionals when you see or hear the tell-tale signs.

5. Making Existing Problems Worse

Besides causing new problems, snow load and the freeze/thaw cycle can further loosen already unsecured roof flashing, dislodge shaky shingles, and pry open gutter seams where caulk has already broken. For this reason, it is a good idea to have a roof inspection and maintenance job done before the winter season begins.

Read more here:  5 Winter Roof Damage Issues Homeowners Need to Know

It is hard to estimate how much snow a roof can handle. It partly depends upon whether or not it is a newer home, as today’s codes are more stringent. Your best bet is to clear the snow with a snow rake before it builds up to the point where it stresses the structure of the building or before ice dams create cause water to back up and leak into the building.

This news clip provides an estimate of how deep the snow can get on your roof before causing problems. Keep in mind that the more moisture in the snow the heavier it is, so these depth measurements might not be as accurate:

If you really want to get an precise assessment for what your roof can handle, there are online snow load calculators. This snow load safety guide from FEMA is also good information to have. An architect engineer would be able to assist you in figuring out this information as well.

This article from is somewhat technical, but it offers the method that snow load is calculated:

How to Compute Roof Snow Loads | Roof Snow Load Calculator

Roof snow loads are computed in pounds per square foot using the ground snow load as the basis for calculation. If you are building a roof on a residential or storage structure in a region that receives snowfall, then you must consider snow load when choosing the design and materials. If too much snow falls on a weak or poorly designed roof, the roof can collapse under the weight of the snow.

The steps below show how to estimate the snow load on a roof using the ground snow load, roof properties, and formulas based on national structural engineering codes.

Step 1: Finding the Ground Snow Load G
The ground snow load is measured in pounds per square foot (psf) over a typical patch of ground during a typical snow snow season. You can either measure it directly, or look it up in your state and local building codes.

Step 2: Finding the Exposure Factor E

Step 3: Finding the Thermal Factor TSanta Sleigh and Reindeer

Step 4: Finding the Roof Slope Factor R

Step 5: Putting It All Together
RSL = 0.7 * G * E * T * R

Read the full post here:  How to Compute Roof Snow Loads | Roof Snow Load Calculator

The real key is whether or not your roof can withstand snow along with reindeer pulling a sleigh loaded with toys. I’m not so sure it is included in the calculating method above, but you need to keep it in mind for the sake of Santa visiting your home tonight. Merry Christmas to all!